JP5546556B2 - Dynamic seal member - Google Patents

Description

  The present invention relates to a dynamic seal member.

According to the method for producing a carbon fiber composite material previously proposed by the present inventors, by using an elastomer, the dispersibility of the carbon nanofiber, which has been considered difficult so far, is improved, and the carbon nanofiber is uniformly distributed in the elastomer. (See, for example, JP-A-2005-97525). According to such a method for producing a carbon fiber composite material, an elastomer and carbon nanofibers are kneaded, and dispersibility of carbon nanofibers having high cohesiveness is improved by shearing force. More specifically, when the elastomer and the carbon nanofiber are mixed, the viscous elastomer penetrates into the carbon nanofiber, and a specific part of the elastomer has high activity of the carbon nanofiber due to chemical interaction. In this state, when a strong shearing force is applied to a mixture of an elastomer having high molecular mobility (elasticity) and carbon nanofibers, the carbon nanofibers are deformed as the elastomer is deformed. The fibers also moved, and the aggregated carbon nanofibers were separated and dispersed in the elastomer by the restoring force of the elastomer due to elasticity after shearing. Thus, by improving the dispersibility of the carbon nanofibers in the matrix, expensive carbon nanofibers can be used efficiently as fillers for composite materials.
Further, according to the heat-resistant sealing material previously proposed by the present inventors, a vapor-grown carbon fiber having an average diameter of more than 30 nm and not more than 200 nm and a mean particle diameter of 25 nm to 500 nm are added to the ternary fluorine-containing elastomer. Carbon black was blended to provide a sealing material with excellent heat resistance (see, for example, International Publication WO / 2009 / 125503A1).

  An object of the present invention is to provide a dynamic seal member excellent in heat resistance and wear resistance.

The dynamic sealing member according to the present invention is
For ternary fluorine-containing elastomer (FKM), carbon nanofibers are included,
The carbon nanofibers are carbon nanofibers having an average diameter of 10 nm to 20 nm or carbon nanofibers having an average diameter of 60 nm to 110 nm and heat-treated at a low temperature,
Carbon nanofibers which the average diameter was low-temperature heat treatment a 60nm~110nm, the ratio of the peak intensity D of around 1300 cm ^-1 to the peak intensity G of around 1600 cm ^-1 measured by Raman scattering spectroscopy (D / G) Is greater than 1.25 and less than 1.6;
The number of breaks in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2.5 N / mm, and a frequency of 1 Hz is 10 times or more.

In the dynamic sealing member according to the present invention,
With respect to 100 parts by mass of the ternary fluorine-containing elastomer (FKM), 0.5 part by mass to 30 parts by mass of carbon nanofibers having an average diameter of 10 nm to 20 nm and 0 part by mass of a filler having an average particle diameter of 5 nm to 300 nm ~ 50 parts by mass,
The compounding quantity of the said carbon nanofiber and the said filler can satisfy | fill following formula (1) and (2).

Wt = 0.09W1 + W2 (1)
5 ≦ Wt ≦ 30 (2)
W1: Blending amount of filler (parts by mass)
W2: Compounding amount (parts by mass) of carbon nanofibers.

In the dynamic sealing member according to the present invention,
4 parts by mass to 30 parts by mass of carbon nanofibers having an average diameter of 60 nm to 110 nm and low-temperature heat treatment, and a filler having an average particle diameter of 5 nm to 300 nm with respect to 100 parts by mass of the ternary fluorine-containing elastomer (FKM) 0 parts by mass to 60 parts by mass,
The compounding quantity of the said carbon nanofiber and the said filler can satisfy | fill following formula (3) and (4).

Wt = 0.1W1 + W2 (3)
10 ≦ Wt ≦ 30 (4)
W1: Blending amount of filler (parts by mass)
W2: Compounding amount (parts by mass) of carbon nanofibers.

In the dynamic sealing member according to the present invention,
The dynamic seal member has a hardness of less than 80;
The number of breaks in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2 N / mm, and a frequency of 1 Hz can be 50 times or more.

In the dynamic sealing member according to the present invention,
The dynamic sealing member has a hardness of 80 or more,
The number of breaks in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2 N / mm, and a frequency of 1 Hz can be 300 times or more.

In the dynamic sealing member according to the present invention,
Wear amount Wa in the high-pressure wear test 25 ° C. is ^{0.010cm 3 / N · m~0.070cm 3 /} N · m,
The wear amount Wa can satisfy the following formula (5).

Wa = (g ₂ −g ₁ ) / (P · L · d) (5)
g ₁ : Mass of the test piece before wear (g)
g ₂ : Mass of the test piece after wear (g)
P: Set weight of weight (N)
L: Wear distance (m)
d: Specific gravity (g / cm ³ ).

In the dynamic sealing member according to the present invention,
The dynamic seal member can be used in an oil field device.

In the dynamic sealing member according to the present invention,
The oil field device may be a logging device that performs logging in a well.

In the dynamic sealing member according to the present invention,
The dynamic seal member may be an endless seal member disposed in the oil field device.

In the dynamic sealing member according to the present invention,
The dynamic seal member may be a stator of a fluid drive motor disposed in the oil field device.

In the dynamic sealing member according to the present invention,
The fluid drive motor may be a mud motor.

In the dynamic sealing member according to the present invention,
The dynamic seal member may be a rotor of a fluid drive motor disposed in the oil field device.

In the dynamic sealing member according to the present invention,
The fluid drive motor may be a mud motor.

In the dynamic sealing member according to the present invention,
The ternary fluorine-containing elastomer (FKM) has a fluorine content of 66 to 70% by mass, a central value of Mooney viscosity (ML _{1 + 4} 121 ° C.) of 25 to 65, and a glass transition point of 0 ° C. or less. it can.

In the dynamic sealing member according to the present invention,
Before the carbon nanofiber is blended with the ternary fluorine-containing elastomer (FKM), rigidity = Lx ÷ D (Lx: distance between adjacent defects of the carbon nanofiber, The average value of the stiffness defined by (D: diameter of carbon nanofiber) can be 3-12.

In the dynamic sealing member according to the present invention,
The filler may be carbon black having an average particle size of 10 nm to 300 nm.

In the dynamic sealing member according to the present invention,
The filler may have an average particle diameter of 5 nm to 50 nm and at least one selected from silica, talc, and clay.

FIG. 1 is a perspective view schematically showing a compression process of carbon nanofibers used for a dynamic seal member according to an embodiment of the present invention. Drawing 2 is a figure showing typically the manufacturing method of the dynamic seal member by the open roll method concerning one embodiment of the present invention. Drawing 3 is a figure showing typically the manufacturing method of the dynamic seal member by the open roll method concerning one embodiment of the present invention. Drawing 4 is a figure showing typically the manufacturing method of the dynamic seal member by the open roll method concerning one embodiment of the present invention. FIG. 5 is a diagram schematically showing a tensile fatigue test of the dynamic seal member according to the embodiment of the present invention. FIG. 6 is a diagram schematically showing a high-pressure wear test of a dynamic seal member according to an embodiment of the present invention. FIG. 7 is a cross-sectional view schematically showing a logging tool for seabed use according to an embodiment of the present invention. FIG. 8 is a partial cross-sectional view schematically showing the logging apparatus of FIG. 7 according to one embodiment of the present invention. FIG. 9 is an X-X ′ cross-sectional view schematically showing a mud motor of the logging apparatus of FIG. 8. FIG. 10 is a cross-sectional view schematically showing an underground logging tool according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail.
The dynamic sealing member according to an embodiment of the present invention includes carbon nanofibers with respect to a ternary fluorine-containing elastomer (FKM), and the carbon nanofibers are carbon nanofibers having an average diameter of 10 nm to 20 nm or Carbon nanofibers having an average diameter of 60 nm to 110 nm and low-temperature heat treatment, and carbon nanofibers having an average diameter of 60 nm to 110 nm and low-temperature heat treatment have a peak intensity around 1600 cm ⁻¹ measured by Raman scattering spectroscopy. The ratio (D / G) of peak intensity D in the vicinity of 1300 cm ^{−1 to} G is greater than 1.25 and less than 1.6, and in a tensile fatigue test at 200 ° C., maximum tensile stress 2.5 N / mm, and frequency 1 Hz. The number of breaks is 10 or more.

(I) Carbon nanofiber The carbon nanofiber will be described.
The carbon nanofibers used in the present embodiment can be carbon nanofibers having an average diameter (fiber diameter) of 10 nm to 20 nm or an average diameter of 60 nm to 110 nm and heat-treated at a low temperature. Since the carbon nanofiber has a relatively small average diameter, the specific surface area is large, the surface reactivity with the matrix FKM is improved, and the carbon nanofibers in the FKM tend to be poorly dispersed. Carbon nanofibers are expected to have moderate flexibility with a microcell structure formed so as to surround the matrix material with carbon nanofibers when the diameter is 10 nm or more. Conversely, when the diameter is 110 nm or less, the microcell structure is large. However, it is expected to have an effect of wear resistance. The micro cell structure formed by the carbon nanofibers can be formed so as to surround the matrix material by a network structure in which the carbon nanofibers are stretched in three dimensions. Carbon nanofibers having an average diameter of 60 nm to 110 nm may further be 70 nm to 100 nm. Carbon nanofibers having an average diameter of 60 nm to 110 nm are subjected to low-temperature heat treatment in order to improve the reactivity with FKM on the surface. The low temperature heat treatment will be described later.

  The average diameter of the carbon nanofiber can be measured by observation with an electron microscope. In the detailed description of the present invention, the average diameter and the average length of the carbon nanofibers are, for example, 5,000 times or more from an electron microscope (the magnification can be appropriately changed depending on the size of the carbon nanofibers) and the diameters of 200 or more locations And the length can be measured and calculated as the arithmetic average value.

  Carbon nanofiber can mix | blend 5 mass part-30 mass parts with respect to 100 mass parts of FKM. In particular, when carbon nanofibers having an average diameter of 10 nm to 20 nm are used, 5 to 30 parts by mass can be blended with respect to 100 parts by mass of FKM, and the average diameter is 60 to 110 nm. When carbon nanofibers subjected to low-temperature heat treatment are used, 10 to 30 parts by mass can be blended with respect to 100 parts by mass of FKM. The carbon nanofibers are 5 parts by mass or more particularly when carbon nanofibers having an average diameter of 10 nm to 20 nm are used, or 10 masses when carbon nanofibers having an average diameter of 60 nm to 110 nm and low-temperature heat treatment are used. Since it is considered that a nano-sized cell structure can be formed by blending more than 15 parts into FKM, there is a tendency to improve the wear resistance, and if the blending amount is 30 parts by weight or less, breakage occurs. Since the elongation (EB) is relatively high, the dynamic seal member tends to be easily attached to the part as well as excellent workability. Moreover, the compounding quantity of carbon nanofiber can be reduced by mix | blending fillers other than carbon nanofiber. When the filler is blended, the carbon nanofiber having an average diameter of 10 nm to 20 nm can be blended in an amount of 0.5 to 30 parts by mass with respect to 100 parts by mass of FKM, and the average diameter is 60 nm to 110 nm of carbon nanofibers can be blended in an amount of 14 to 60 parts by mass with respect to 100 parts by mass of FKM. Here, “parts by mass” indicates “phr” unless otherwise specified, and “phr” is an abbreviation for “parts per undred of resin or rubber”, and represents the percentage of external additives such as additives to rubber and the like. It is.

  The carbon nanofibers can be relatively rigid fibers having an average stiffness value of 3 to 12 before being blended with the ternary fluorine-containing elastomer (FKM). In particular, carbon nanofibers having an average diameter of 10 nm to 20 nm can have an average stiffness value of 3 to 5, and carbon nanofibers having an average diameter of 60 nm to 110 nm have an average stiffness value of 9 to Can be twelve. Stiffness refers to the rigidity of carbon nanofibers, and is obtained by measuring and calculating the length and diameter of the almost unbent portions of carbon nanofibers taken with a microscope or the like. Sometimes referred to as the bending index. The bent portion of the carbon nanofiber is a defect of the fiber, and appears as a white line that crosses the fiber in the width direction with an electron microscope. When the length of the substantially straight portion of the carbon nanofiber that is not bent is Lx and the diameter of the carbon nanofiber is D, the rigidity is defined as Lx ÷ D, and the arithmetic average value is calculated. Therefore, carbon nanofibers with low rigidity are bent at short intervals, and carbon nanofibers with high rigidity are long straight portions and are not bent. The measurement of the length Lx of the linear portion of the carbon nanofiber is performed in a state where the photographic data of the carbon nanofiber photographed at 10,000 to 50,000 times is enlarged, for example, 2 to 10 times. In the enlarged photograph, a bent portion (defect) that crosses the fiber in the width direction can be confirmed. The distance between adjacent bent portions (defects) thus confirmed is measured by measuring a plurality of, for example, 200 or more locations as the length Lx of the linear portion of the carbon nanofiber.

  Carbon nanofibers are so-called multi-wall carbon nanotubes (MWNT: multi-wall carbon nanotubes) having a cylindrical shape formed by winding one sheet of graphite (graphene sheet) having a carbon hexagonal mesh surface, and an average diameter of 10 to 20 nm. Examples of carbon nanofibers include VGCF-X (VGCF: registered trademark of Showa Denko KK) manufactured by Showa Denko, Baytubes of Bayer MaterialScience, NC-7000 of Nanosyl, etc. Examples of carbon nanofibers having an average diameter of 60 nm to 110 nm include VGCF-S from Showa Denko. A carbon material partially having a carbon nanotube structure can also be used. In addition to the name “carbon nanotube”, it may be called “graphite fibril nanotube” or “vapor-grown carbon fiber”.

Carbon nanofibers can be obtained by a vapor deposition method. The vapor phase growth method is also called a catalytic chemical vapor deposition (CCVD), in which a gas such as a hydrocarbon is pyrolyzed in the presence of a metal catalyst in the presence of a metal-based catalyst to perform untreated first carbon nano-particles. A method of manufacturing a fiber. The vapor phase growth method will be described in more detail. For example, an organic compound such as benzene or toluene is used as a raw material, an organic transition metal compound such as ferrocene or nickelcene is used as a metal catalyst, and these are used together with a carrier gas at a high temperature such as 400 ° C. It is introduced into a reaction furnace set to a reaction temperature of ˜1000 ° C., and the floating reaction method (floating reaction method) in which the first carbon nanofibers are generated in a floating state or on the reaction furnace wall, or alumina, magnesium oxide, etc. A catalyst-supporting reaction method (substrate reaction method) in which metal-containing particles supported on ceramics are brought into contact with a carbon-containing compound at a high temperature to generate carbon nanofibers on a substrate can be used. Carbon nanofibers having an average diameter of 10 nm to 20 nm can be obtained by a catalyst-supporting reaction method, and carbon nanofibers having an average diameter of 60 nm to 110 nm can be obtained by a floating flow reaction method. The diameter of the carbon nanofiber can be adjusted by, for example, the size of the metal-containing particles and the reaction time. Carbon nanofibers having an average diameter of 10nm~20nm may nitrogen adsorption specific surface area of ^{10m 2} / ^g~500m 2 / g, can be more 100m ² / g~350m ² / g, in particular, it can be a 150m ² / g~300m ² / g.

Carbon nanofibers having an average diameter of 60 nm to 110 nm and subjected to low-temperature heat treatment can be obtained by low-temperature heat treatment of so-called untreated carbon nanofibers obtained by vapor phase growth. In this low-temperature heat treatment, untreated carbon nanofibers can be heat-treated at a temperature higher than the reaction temperature in the vapor phase growth method at 1100 ° C. to 1600 ° C. The temperature of this heat treatment can further be 1200 ° C. to 1500 ° C., in particular 1400 ° C. to 1500 ° C. When the temperature of the low-temperature heat treatment is higher than the reaction temperature of the vapor phase growth method, the surface structure of the carbon nanofibers can be adjusted and surface defects can be reduced. Further, by setting the low-temperature heat treatment temperature to 1100 ° C. to 1600 ° C., the surface reactivity with FKM is improved, and the dispersion of carbon nanofibers in the matrix material can be further improved. The carbon nanofibers low-temperature heat treatment as is and the ratio of the peak intensity D of around 1300 cm ^-1 to the peak intensity G of around 1600 cm ^-1 measured by Raman scattering spectroscopy (D / G) is greater than 0.9 It may be less than 1.6, and may be 1.0 to 1.4. In particular, when the temperature of the heat treatment is 1400 ° C. to 1500 ° C., it may be 1.0 to 1.2. In the Raman spectrum of the carbon nanofibers low-temperature heat treatment, the absorption peak intensity D of around 1300 cm ^-1 is the absorption based on defects in the crystal that forms the carbon nanofibers, the absorption peak intensity G of around 1600 cm ^-1 is carbon nanofiber Absorption based on crystals that form For this reason, the smaller the ratio (D / G) between the peak intensity D and the peak intensity G, the higher the degree of crystallization of the carbon nanofibers. Therefore, the smaller the ratio of the peak intensity D to the peak intensity G (D / G), the higher the degree of graphitization (graphitization), and the carbon nanofibers with fewer defects on the surface. Therefore, low-temperature heat-treated carbon nanofibers having a ratio (D / G) of the peak intensity D to the peak intensity G in the above range have a non-crystalline portion on the surface, and thus have good wettability with FKM. Since the carbon nanofibers subjected to low-temperature heat treatment have relatively few defects, the strength of the carbon nanofibers can be sufficient.

  Usually, carbon nanofibers produced by a vapor phase growth method are heat-treated at 2000 ° C. to 3200 ° C. in an inert gas atmosphere so as to perform so-called graphitization (crystallization) treatment. Impurities such as amorphous deposits and remaining catalytic metals deposited on the surface are removed. The graphitized carbon nanofiber has a relatively low reactivity with FKM on its surface. Carbon nanofibers having an average diameter of 10 nm to 20 nm and carbon nanofibers having an average diameter of 60 nm to 110 nm and subjected to low-temperature heat treatment can be used as they are without performing such graphitization treatment. As described above, the surface of the carbon nanofiber not subjected to the graphitization treatment has a moderately non-crystalline portion, so that the wettability with the FKM tends to be good.

  FIG. 1 is a perspective view schematically showing a compression process of carbon nanofibers used for a dynamic seal member according to an embodiment of the present invention. The carbon nanofiber can be further compressed. The carbon nanofibers can be granulated by the compression treatment. Further, the carbon nanofibers produced by the vapor phase growth method include carbon nanofibers having branched portions as they are, and the compression treatment can be performed at a high pressure for cutting the carbon nanofibers at least from the branched portions. . In the compression treatment, carbon nanofibers 60 as raw materials are introduced between a plurality of, for example, at least two rolls 72 and 74 that continuously rotate in the direction of the arrow in the figure, and shearing force and compression force are applied to the carbon nanofibers For example, a dry compression granulator 70 such as a roll press machine or a roller compactor (roll type high pressure compression molding machine) can be employed. By putting a plurality of carbon nanofibers 60 manufactured by the vapor phase growth method into a dry compression granulator 70 and compressing them, an aggregate of a plurality of carbon nanofibers 80 subjected to the compression process can be obtained. The roll press machine normally uses a smooth roll in which pockets are not engraved on the outer peripheral surface of the roll or a roll in which pockets are engraved. In this embodiment, a smooth roll is used in order to apply a compressive force evenly to the carbon nanofibers. be able to. Further, the interval between the two rolls is set to 0 mm, that is, the rolls are in contact with each other, and a predetermined compression force F, for example, 980 to 2940 N / cm can be applied between the two rolls, and further 1500 to 2500 N. / Cm is preferred. The compressive force F can be set to an appropriate pressure while confirming the presence or absence of a branched portion in the obtained carbon nanofiber assembly 80 with an electron microscope or the like. If it is 980 N / cm or more, the carbon nanofiber which has a branch part can be cut | disconnected by a branch part. Such compression treatment can be performed a plurality of times, for example, about twice in order to homogenize the entire carbon nanofiber. In a granulator, generally a binder such as water is often blended to bind powder, but the compression treatment in the present embodiment is a dry granulation that does not use a binder for binding carbon nanofibers to each other. Can be. This is because if a binder is used, it may be difficult to disperse the carbon nanofibers in a later step, and a step of removing the binder may be further required. In addition, after compressing between two rolls by the dry compression granulator 70 and forming into an aggregate of plate-like (flakes) carbon nanofibers 80, it is further crushed by a pulverizer or the like and adjusted to a desired size. An aggregate of the granulated carbon nanofibers 80 can be produced. The pulverizer at this time, for example, rotates the rotary blade at high speed and crushes the aggregate of carbon nanofibers 80 by the shearing force, and uses a screen to adjust the size only through the aggregate of carbon nanofibers 80 having an appropriate size or less. It can be performed. The size of the aggregates of the carbon nanofibers 80 varies greatly only by the compression treatment, but the particle size of the aggregates of the carbon nanofibers 80 is adjusted to an appropriate size by further crushing in this way, so that the matrix material It is possible to prevent the carbon nanofiber aggregates from being biased when kneaded. By this compression treatment, the carbon nanofibers are cut at the branching portions, and the desired bulk density that does not become soft becomes easy to handle during processing. For example, the carbon nanofibers can be granulated into a plate-like carbon nanofiber aggregate. .

(II) Ternary fluorine-containing elastomers Ternary fluorine-containing elastomers are synthetic rubbers of vinylidene fluoride containing fluorine atoms in their molecules, and are also called ternary fluorine rubbers. For example, vinylidene fluoride (VDF) -hexafluoropropylene (HFP) -tetrafluoroethylene (TFE) terpolymer (VDF-HFP-TFE), vinylidene fluoride (VDF) -perfluoro (methyl vinyl ether) (FMVE) -tetrafluoroethylene (TFE) terpolymer (VDF-HFP-TFE) and the like. Examples of the ternary fluorine-containing elastomer include DuPont's trade name Viton and Daikin Industries' trade name Daiel G. In the following description, the ternary fluorine-containing elastomer is abbreviated as FKM. The ternary fluorine-containing elastomer preferably has a weight average molecular weight of 50,000 to 300,000. If the molecular weight of the ternary fluorine-containing elastomer is within this range, the ternary fluorine-containing elastomer molecules are entangled with each other and connected to each other, so the ternary fluorine-containing elastomer disperses the carbon nanofibers. Can have good elasticity. The ternary fluorine-containing elastomer has viscosity, so that the aggregated carbon nanofibers can easily enter each other, and the carbon nanofibers can be separated by having elasticity. If the weight average molecular weight of the ternary fluorine-containing elastomer is smaller than 50,000, the ternary fluorine-containing elastomer molecules cannot be sufficiently entangled with each other, and elasticity is exerted even if a shearing force is applied in a later step. Since it is small, the effect of dispersing the carbon nanofibers tends to be small. If the weight average molecular weight of the ternary fluorine-containing elastomer is larger than 300,000, the ternary fluorine-containing elastomer tends to be too hard and difficult to process. FKM is slightly inferior in wear resistance to hydrogenated acrylonitrile-butadiene rubber (HNBR), but has excellent high temperature characteristics. It can be used as a dynamic seal member. FKM can also be used in a high temperature environment of 175 ° C to 200 ° C. Moreover, FKM can be excellent in abrasion resistance at high temperature, although it is inferior in chemical resistance compared with a tetrafluoroethylene-propylene copolymer (FEPM). The FKM used in this embodiment can have a fluorine content of 66 mass% to 70 mass%, a central value of Mooney viscosity (ML _{1 + 4} 121 ° C.) of 25 to 65, and a glass transition point of 0 ° C. or lower. When the fluorine content is 66% by mass or more, the heat resistance is excellent, and when the fluorine content is 70% by mass or less, the chemical resistance such as alkali resistance, acid resistance, and chlorine resistance is excellent. Moreover, when the median value of Mooney viscosity (ML _{1 + 4} 121 ° C.) is 25 or more, basic required performance such as tensile strength (TB) and compression set (CS) can be obtained, and Mooney viscosity (ML _{1 + 4} 121 ° C.). If the center value of) is 65 or less, it has an appropriate viscosity and can be processed. For example, exploration of underground resources may be conducted under the sea floor, but the sea floor is at a temperature of about 4 ° C due to high pressure, and if the FKM's glass transition point is 0 ° C or less, it will dynamically move from the sea floor to a hot exploration zone. It can be used as a seal member.

(III) Filler The filler has an average particle size of 5 nm to 300 nm. As the filler, at least one of carbon black, silica, clay, talc and the like that can be used as an elastomer filler can be selected. The carbon black may have an average particle size of 10 nm to 300 nm. Silica, talc and clay may have an average particle size of 5 nm to 50 nm. The filler in this embodiment does not contain carbon nanofibers.

  By blending the filler into the FKM, the matrix region of the FKM can be divided into minute sizes by the filler, and the matrix region divided into the minute sizes may be reinforced with carbon nanofibers. The compounding quantity of carbon nanofiber can be decreased by mix | blending.

  The aspect ratio of the filler is about 10 times or more that of the carbon nanofibers, and the compounding amount of the carbon nanofibers is, for example, 4.5 parts by mass to 5 parts by mass by blending 50 parts by mass of the filler from the experimental results. Can be reduced.

  The dynamic sealing member may include 0.5 to 30 parts by mass of carbon nanofibers with respect to 100 parts by mass of FKM. Depending on the type of carbon nanofibers or the presence or absence of a filler, carbon nanofibers may be included. The blending amount of can be changed as appropriate.

  When carbon nanofibers having an average diameter of 10 nm to 20 nm are used, 0.5 parts by mass to 30 parts by mass of carbon nanofibers and 0 part by mass to 50 parts by weight of filler having an average particle diameter of 5 nm to 300 nm are obtained with respect to 100 parts by mass of FKM. A mass part. At this time, the compounding amount of the carbon nanofiber and the filler in the dynamic seal member is expressed by the formula when the compounding amount (part by mass) of the filler is W1 and the compounding amount (mass part) of the carbon nanofiber is W2. (1): Wt = 0.09W1 + W2 and formula (2): 5 ≦ Wt ≦ 30 can be satisfied. Therefore, when the filler is not included, carbon nanofibers having an average diameter of 10 nm to 20 nm can be included at least 5 parts by mass. When the carbon nanofiber is 0.5 parts by mass, the filler is 50 parts by mass. Can be included.

  When carbon nanofibers having an average diameter of 60 nm to 110 nm and subjected to low temperature heat treatment are used, 4 to 30 parts by mass of carbon nanofibers and a filler having an average particle diameter of 5 to 300 nm with respect to 100 parts by mass of FKM. 0 parts by mass to 60 parts by mass. At this time, the compounding amount of the carbon nanofiber and the filler in the dynamic seal member is expressed by the formula when the compounding amount (part by mass) of the filler is W1 and the compounding amount (mass part) of the carbon nanofiber is W2. (3): Wt = 0.1W1 + W2 and formula (4): 10 ≦ Wt ≦ 30 can be satisfied. Therefore, when the filler is not included, the carbon nanofibers having an average diameter of 60 nm to 110 nm and heat-treated at a low temperature can be included at least 10 parts by mass. When the carbon nanofibers are 4 parts by mass, the filler is added. 60 parts by mass can be included.

(IV) Method for Producing Dynamic Seal Member A method for producing a dynamic seal member according to one embodiment of the present invention is such that carbon nanofibers are mixed with FKM and uniformly dispersed in the FKM by shearing force. And obtaining a carbon fiber composite material. The dynamic seal member can be obtained by molding a carbon fiber composite material into a desired shape. In this step, as the carbon nanofiber, a carbon nanofiber aggregate obtained by compression treatment can be used. This process will be described in detail with reference to FIGS.

2-4 is a figure which shows typically the manufacturing method of the dynamic seal member by the open roll method concerning one Embodiment of this invention.
As shown in FIGS. 2 to 4, the first roll 10 and the second roll 20 in the two-roll open roll 2 are arranged at a predetermined interval d, for example, 0.5 mm to 1.5 mm. 2 to 4, the motor rotates in the direction indicated by the arrow at the rotational speeds V1 and V2 in the normal direction or the reverse direction. First, as shown in FIG. 2, the FKM 30 wound around the first roll 10 is masticated, and the FKM molecular chain is appropriately cut to generate free radicals. The free radicals of FKM generated by mastication are likely to be combined with carbon nanofibers.
Next, as shown in FIG. 3, the carbon nanofibers 80 and, if necessary, a filler (not shown) are put into the bank 34 of the FKM 30 wound around the first roll 10 and kneaded. The temperature of the FKM 30 in this kneading can be, for example, 100 ° C. to 200 ° C., and further can be 150 ° C. to 200 ° C. Thus, it is considered that the FKM easily enters the gap between the carbon nanofibers 80 by kneading the FKM 30 and the carbon nanofibers 80 at a relatively high temperature as compared with the thin type. The step of mixing the FKM 30 and the carbon nanofiber 80 is not limited to the open roll method, and for example, a closed kneading method or a multi-screw extrusion kneading method can be used.

  Furthermore, as shown in FIG. 4, the roll interval d between the first roll 10 and the second roll 20 is set to, for example, 0.5 mm or less, more preferably 0 to 0.5 mm, and the mixture 36 is Insert into the open roll 2 and perform thinning once to several times. For example, the thinning can be performed about 1 to 10 times. When the surface speed of the first roll 10 is V1 and the surface speed of the second roll 20 is V2, the ratio of the surface speeds (V1 / V2) in thinness is 1.05 to 3.00. Furthermore, it is preferable that it is 1.05-1.2. By using such a surface velocity ratio, a desired shear force can be obtained. The carbon fiber composite material 50 extruded from between the narrow rolls as described above is greatly deformed as shown in FIG. 4 due to the restoring force due to the elasticity of the FKM 30, and the carbon nanofibers 80 move together with the FKM 30 at that time. The carbon fiber composite material 50 obtained through thinning is rolled with a roll and dispensed into a sheet having a predetermined thickness. In this thinning process, in order to obtain as high a shearing force as possible, the roll temperature is set to a relatively low temperature of, for example, 0 to 50 ° C., more preferably 5 to 30 ° C., and the measured temperature of the FKM 30 is also 0. It can be adjusted to -50 ° C. Due to the shearing force thus obtained, a high shearing force acts on the FKM 30, and the aggregated carbon nanofibers 80 are separated from each other so as to be pulled out by FKM molecules one by one and dispersed in the FKM 30. . In particular, since the FKM 30 has elasticity, viscosity, and chemical interaction with the carbon nanofibers 80, the carbon nanofibers 80 can be easily dispersed. And the carbon fiber composite material 50 excellent in the dispersibility and dispersion stability of carbon nanofiber 80 (it is hard to re-aggregate carbon nanofiber) can be obtained.

  More specifically, when FKM and carbon nanofibers are mixed with an open roll, viscous FKM enters the carbon nanofibers, and a specific portion of the FKM is chemically interacted with the carbon nanofibers. Binds to highly active moieties. For example, when the surface of the carbon nanofiber is not graphitized or has a moderately high activity by low-temperature heat treatment or the like, it is particularly easy to bind to FKM molecules. Next, when a strong shearing force acts on the FKM, the carbon nanofibers move with the movement of the FKM molecules, and the aggregated carbon nanofibers are separated by the restoring force of the FKM due to elasticity after shearing, Will be dispersed in the FKM. According to the present embodiment, when the carbon fiber composite material is pushed out between narrow rolls, the carbon fiber composite material is deformed thicker than the roll interval by the restoring force due to the elasticity of FKM. The deformation can be presumed to cause the carbon fiber composite material with a strong shearing force to flow more complicatedly and disperse the carbon nanofibers in the FKM. And once disperse | distributed carbon nanofiber is prevented from reaggregating by the chemical interaction with FKM, and can have favorable dispersion stability.

  The step of dispersing carbon nanofibers in FKM by shearing force is not limited to the open roll method, and a closed kneading method or a multi-screw extrusion kneading method can also be used. In short, in this step, it is sufficient that a shearing force capable of separating the aggregated carbon nanofibers can be given to the FKM. In particular, the open roll method is preferable because it can measure and manage not only the roll temperature but also the actual temperature of the mixture. A cross-linking agent can be mixed with the carbon fiber composite material dispensed before, during, or after passing through the FKM and the carbon nanotube, and the cross-linked carbon fiber composite material can be cross-linked. it can. Crosslinking of FKM can be performed by polyamine vulcanization, polyol vulcanization, or peroxide vulcanization, and peroxide vulcanization having excellent chemical resistance can be used.

  The dynamic seal member is molded into a desired shape, for example, endless by a rubber molding process generally employed with a carbon fiber composite material, such as an injection molding method, a transfer molding method, a press molding method, an extrusion molding method, or a calendering method. You can get it. The dynamic seal member can be made of a crosslinked carbon fiber composite material.

  In the method for producing a carbon fiber composite material according to the present embodiment, a compounding agent usually used in FKM processing can be added. A well-known thing can be used as a compounding agent. Examples of the compounding agent include a crosslinking agent, a vulcanizing agent, a vulcanization accelerator, a vulcanization retarder, a softening agent, a plasticizer, a curing agent, a reinforcing agent, a filler, an antiaging agent, and a coloring agent. it can. These compounding agents can be added to the FKM at an appropriate time during the mixing process. As the crosslinking agent, peroxide can be used, for example, before carbon nanofibers are mixed with FKM, together with carbon nanofibers, or after carbon nanofibers and FKM are mixed, for example, for preventing scorch. Therefore, a crosslinking agent can be mix | blended with the uncrosslinked carbon fiber composite material after passing through.

(V) Dynamic seal member The dynamic seal member can be excellent in physical properties at high temperatures and excellent in wear resistance by reinforcing FKM with carbon nanofibers. The dynamic seal member can have a known form, for example, can be endless, such as a so-called O-ring, a square seal with a rectangular cross-sectional shape, a so-called D-ring with a cross-sectional shape, or a cross-sectional shape. X-shaped so-called X ring, cross-sectional shape E-shaped so-called E-ring, cross-sectional shape V-shaped so-called V-ring, cross-sectional shape U-shaped U-ring, cross-sectional shape L-shaped L-ring Etc. can be adopted. The dynamic seal member may be a stator or rotor of a fluid drive motor such as a mud motor.

FIG. 5 is a diagram schematically showing a tensile fatigue test of the dynamic seal member according to the embodiment of the present invention.
As shown in FIG. 5, the tensile fatigue test of the dynamic seal member in the present embodiment is a strip-like carbon fiber composite material of 10 mm long × 4 mm wide × 1 mm thick manufactured in the above (IV). The test piece 100 is cut out, a notch 106 having a depth of 1 mm is inserted in the width direction from the center of the long side 102 of the test piece 100, and the vicinity of the short sides 104 and 104 at both ends of the test piece 100 is held by the chucks 110 and 110. In the air atmosphere, the tensile load is repeatedly applied in the direction of arrow T in FIG. 5 at a frequency of 1 Hz (0 N / mm to 2.5 N / mm when the maximum tensile stress is 2.5 N / mm, and the maximum tensile stress is 2 N / mm. In this case, 0 N / mm to 2 N / mm) can be applied to break or measure the number of repetitions up to 1 million times. The cut 106 of the test piece 100 can be formed by cutting to a depth of 1 mm with a razor blade. Although several measurement methods have been proposed so far for the abrasion resistance test of the rubber composition, it is considered that the abrasion resistance can be evaluated by such a tensile fatigue test. The phenomenon in which the rubber composition wears due to friction is considered to occur as the rubber composition is torn on the contacted surface. Therefore, the test piece is notched 106 and a tensile fatigue test is performed. If the number is large, it can be estimated that the wear resistance of the dynamic seal member is good. The dynamic seal member contains carbon nanofibers with respect to the ternary fluorine-containing elastomer (FKM), and the number of breaks in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2.5 N / mm, and a frequency of 1 Hz is 10 times or more. It is. The dynamic sealing member may further have a number of breaks of 30 or more in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2.5 N / mm, and a frequency of 1 Hz. When the dynamic seal member has a hardness of less than 80, the number of breaks in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2 N / mm, and a frequency of 1 Hz can be 50 or more. When the dynamic seal member has a hardness of 80 or more, the number of breaks in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2 N / mm, and a frequency of 1 Hz can be 300 times or more, and more than 500 times. it can. The application of the dynamic seal member may be selected depending on the hardness, and it is considered that there is an important relationship between the hardness and the wear resistance of the dynamic seal member. For example, when comparing the wear resistance of the dynamic seal members of different materials, the wear resistance of the dynamic seal members having the same hardness can be compared. When a medium-hardness dynamic seal member with a hardness of less than 80 is compared with a high-hardness dynamic seal member with a hardness of 80 or more, the number of breaks varies greatly. There is a tendency that the difference in wear resistance is small in the high-pressure wear test using. The hardness in the present invention is a JIS-A hardness measured based on JIS K 6253.

Further, it can be estimated that the wear resistance of the dynamic seal member is affected by the thickness of the carbon nanofiber, the wettability of the surface, or the presence or absence of a filler. The dynamic sealing member has an average diameter of 0.5 to 30 parts by mass of carbon nanofibers having an average diameter of 10 nm to 20 nm and an average particle diameter of 5 to 300 nm with respect to 100 parts by mass of a ternary fluorine-containing elastomer (FKM). The blending amount of the carbon nanofibers and the filler can satisfy the following formulas (1) and (2). Furthermore, the compounding amount of the carbon nanofibers having an average diameter of 10 nm to 20 nm can be 1 part by mass to 30 parts by mass, particularly 5 parts by mass to 30 parts by mass.
Wt = 0.09W1 + W2 (1)
5 ≦ Wt ≦ 30 (2)
W1: Blending amount of filler (parts by mass)
W2: Compounding amount (parts by mass) of carbon nanofibers.

The dynamic sealing member has an average diameter of 60 nm to 110 nm and low temperature heat treated carbon nanofibers of 4 to 30 parts by mass and an average particle diameter of 5 nm with respect to 100 parts by mass of a ternary fluorine-containing elastomer (FKM). The blending amount of carbon nanofibers and the filler can satisfy the following formulas (3) and (4). Furthermore, the blending amount of the carbon nanofibers having an average diameter of 60 nm to 110 nm and subjected to low temperature heat treatment can be 5 parts by mass to 30 parts by mass, and further can be 10 parts by mass to 30 parts by mass.
Wt = 0.1W1 + W2 (3)
10 ≦ Wt ≦ 30 (4)
W1: Blending amount of filler (parts by mass)
W2: Compounding amount (parts by mass) of carbon nanofibers.

FIG. 6 is a diagram schematically showing a wear test of the dynamic seal member according to the embodiment of the present invention.
As shown in FIG. 6, the high-pressure wear test of the dynamic seal member is performed using a DIN wear tester 120, and the crosslinked carbon fiber composite material sample manufactured in (IV) is cut into a disk-shaped test piece 126. The weight 129 can be pressed against the surface of the disk-shaped grindstone 128 that rotates the test piece 126 with a predetermined load to be worn. The test piece 126 is disposed in the water 124 of the water tank 122, and the temperature rise of the test piece 126 due to frictional heat can be suppressed. The disk-shaped test piece 126 can have a diameter of 8 mm and a thickness of 6 mm, and the weight 129 can press the test piece 126 against the disk-shaped grindstone 128 with a load of 49.0 N using, for example, 5 kgf. The surface of the water can have a roughness of # 100, the water 124 in the water tank 122 can be set to room temperature to 80 ° C., and the distance between the test piece 126 and the disc-shaped grindstone 128 is 20 m. Otherwise, the mass (g) of the test piece before and after the abrasion test can be measured in the same manner as the DIN-53516 abrasion test.

Dynamic seal member wear amount Wa in the high-pressure wear test 25 ° C. was ^{0.010cm 3 / N · m~0.070cm 3 /} N · m, the wear amount Wa, it satisfies the following formula (5) Can do. Furthermore, the dynamic seal member can wear amount Wa is ^{0.020cm 3 / N · m~0.060cm 3 /} N · m, in particular 0.020cm ³ / N · m~0.050cm ³ / N · m.
Wa = (g ₂ −g ₁ ) / (P · L · d) (5)
g ₁ : Mass of the test piece before wear (g)
g ₂ : Mass of the test piece after wear (g)
P: Set weight of weight (N)
L: Wear distance (m)
d: Specific gravity (g / cm ³ ).

A carbon fiber composite material for forming a dynamic seal member includes FKM and carbon nanofibers manufactured by a vapor growth method uniformly dispersed in the FKM. The uncrosslinked carbon fiber composite material has a characteristic relaxation time (T2′HE / 150 ° C.) of 500 to 1200 μsec, measured at 150 ° C. by the Hahn echo method using pulsed NMR and the observation nucleus at ¹ H. Can be further 500 to 1300 microseconds, in particular 500 to 1100 microseconds. Note that “HE” in the characteristic relaxation time (T2′HE) is a notation used to distinguish from “SE” in the solid echo method described later. The characteristic relaxation time (T2′HE) by the Hahn-echo method is a measure showing the molecular mobility of FKM, and represents the average relaxation time of a multicomponent system. Therefore, the characteristic relaxation time (T2′HE) is an average value of a plurality of relaxation times detected by the Hahn-echo method, and is expressed as “1 / T2′HE = fa / T2a + fb / T2b + fc / T2c. Can do. A carbon fiber composite material in which carbon nanofibers are dispersed represents the ability of carbon nanofibers to restrain FKM molecules as a matrix. (T2'HE / 150 ° C) is a blending amount of carbon nanofibers compared to FKM alone. It becomes small according to. Therefore, even if it is a carbon fiber composite material mixed with carbon nanofibers, the characteristic relaxation time by the Hahn echo method at 150 ° C. is difficult because the FKM molecules are difficult to bind to the whole when the carbon nanofibers are not uniformly dispersed. (T2′HE / 150 ° C.) is considered not to be significantly different from that of FKM alone.

The uncrosslinked carbon fiber composite material has a characteristic relaxation time (T2′SE / 150 ° C.) of 10 to 700 μs measured at 150 ° C. by solid echo method using pulsed NMR and observation nucleus at ¹ H. Furthermore, the characteristic relaxation time (T2′SE / 150 ° C.) can be 10 to 500 μsec, and the characteristic relaxation time (T2′SE / 150 ° C.) can be 10 to 200 μsec. The characteristic relaxation time (T2′SE) by the solid echo method is a measure showing the non-uniformity of the magnetic field due to the carbon nanofibers, and represents the average relaxation time of a multicomponent system. Therefore, the characteristic relaxation time (T2′SE) is an average value of a plurality of relaxation times detected by the Hahn echo method, and is expressed as “1 / T2′SE = fa / T2a + fb / T2b + fc / T2c. Can do. The carbon fiber composite material in which carbon nanofibers are dispersed causes magnetic field inhomogeneity due to the uniform dispersion of carbon nanofibers, and the characteristic relaxation time (T2'SE / 150 ° C) by the solid echo method at 150 ° C is FKM. It becomes smaller according to the compounding quantity of carbon nanofiber than a simple substance. In addition, even when carbon nanofibers are mixed with carbon nanofibers, non-uniformity of the magnetic field is not introduced when carbon nanofibers are not uniformly dispersed. It is considered that the relaxation time (T2′SE / 150 ° C.) is almost the same as that of FKM alone.

  In addition, around the carbon nanofibers, a part of FKM is considered to be an aggregate of FKM molecules adsorbed by attacking the surface of the carbon nanofibers and free radicals generated by the molecular chain cleavage during kneading. An interfacial phase is formed. The interfacial phase is considered to be similar to a bound rubber formed around carbon black when, for example, an elastomer and carbon black are kneaded. Such an interfacial phase is coated and protected with carbon nanofibers, and by blending more than a predetermined amount of carbon nanofibers, the interfacial phase is surrounded by an interfacial phase and is divided into nanometer-sized FKMs. Are estimated to form small cells. By forming such small cells almost uniformly throughout the carbon fiber composite material, it is possible to expect an effect that exceeds the effect of simply combining the two materials.

Furthermore, according to one embodiment of the present invention, the dynamic seal member can be used for oil field applications with severe conditions. As described above, this dynamic sealing member not only has high mechanical properties at a high temperature of 200 ° C. or higher, but also maintains high mechanical properties at a relatively low temperature of 25 ° C. or lower and a high pressure of 5000 psi or higher, Alternatively, it has high wear resistance, low friction, high gas resistance against H ₂ S, CH ₄ or CO ₂ , high chemical resistance, or high thermal conductivity. The oil field application will be described in detail below.

(VI) Oil field use The dynamic seal member for oil field use can be used for an oil field apparatus (Oilfield Apparatus), for example. The dynamic seal member of the oil field device can be used in, for example, a logging machine, a rotary machine such as a motor, a reciprocating machine such as a piston, or the like. A typical embodiment of the oil field apparatus will be described below.

  For example, the logging equipment is used for physical properties such as formations and oil reservoirs in and around excavated boreholes, geometric properties of wells or casings (bore diameter, orientation, slope, etc.), flow of oil reservoirs, etc. Is a device for recording the behavior of each at every depth, and can be used, for example, in an oil field. Examples of the logging device for oil field use include the subsea use shown in FIG. 7 and the underground use shown in FIG. The logging equipment includes wireline logging (muline logging) and mud logging (mud logging), etc., and logging logging (LWD) with measuring equipment installed in the drilling assembly, Measurement during drilling (MWD: Measurement While Drilling). Since these logging devices work deep in the ground, the surrounding environment becomes harsh for the dynamic seal member, and resists friction and maintains a liquid-tight state when exposed to high temperatures, particularly 175 ° C or higher. In some cases, heat resistance higher than that of the HNBR composite material may be required.

  The dynamic seal member of one embodiment of the present invention used in the logging apparatus will be described with reference to FIGS. FIG. 7 is a cross-sectional view schematically showing a logging tool for seabed use according to an embodiment of the present invention. FIG. 8 is a partial cross-sectional view schematically showing the logging apparatus of FIG. 7 according to one embodiment of the present invention. FIG. 9 is an X-X ′ cross-sectional view schematically showing a mud motor of the logging apparatus of FIG. 8. FIG. 10 is a cross-sectional view schematically showing an underground logging tool according to an embodiment of the present invention.

  As shown in FIG. 7, the exploration of underground resources by the measuring equipment installed in the drilling assembly in the ocean is, for example, a well 156 composed of a vertical hole or a horizontal hole provided in the seabed 154 from the platform 150 floating in the sea 152. For example, a bottom hole assembly (BHA) 160 is made to enter as a logging device, and a geological structure in the ground is searched to search for the presence of, for example, petroleum as a target material. The hole bottom assembly 160 is fixed to the tip of a long drill string 153 extending from the platform 150, for example, and has a plurality of modules. For example, in order from the tip, a drill bit 162, a rotation operation system (RSS: A rotary steerable system 164, a mud motor 166, a measurement module 168 during excavation, and a logging module 170 during excavation may be connected. The drill bit 162 can advance excavation by rotation at the bottom portion 156 a of the well 156.

  The rotation operation system 164 shown in FIG. 8 has a deflection mechanism (not shown) that deflects the bit in a certain direction while rotating the drill bit 162, and enables tilt-controlled excavation. The rotary operation system 164 can apply the dynamic seal member of one embodiment of the present invention. The rotary operating system 164 requires a dynamic seal member with high wear resistance, for example at up to about 210 ° C., and a dynamic seal member with high chemical resistance to exposure to various mud water. Conventional dynamic seal members tended to fail due to rubber wear and tear. In particular, in harsh chemical environments, the problem tended to be serious. While dynamic seal members for rotary steerable systems such as those shown in US 2006/0157283 are required to perform at high sliding speeds (˜100 mm / sec) The problems of dynamic seal members tended to be exacerbated by the degradation of elastomer properties and wear characteristics of drilling fluids at operating temperatures. In contrast, by using the dynamic seal member of one embodiment of the present invention for the dynamic seal member of the rotary operation system 164, in addition to the characteristics of the dynamic seal member described above, it is sealed from the drilling mud containing particles. The above problems can be solved by high wear resistance to achieve, better chemical resistance to a wide range of drilling fluids, and better mechanical properties at high temperatures that reduce tearing. The rotation operation system 164 includes a non-rotating cylindrical casing 164a, a transmission shaft 164b that passes through the casing 164a and transmits the rotational force of the mud motor 166 to the drill bit 162, and the transmission shaft 164b within the casing 164a. And a dynamic seal member 164c that is rotatably supported. The dynamic seal member 164c can be, for example, an endless O-ring fitted in an annular groove provided in the housing 164a, and has a function of sealing with the surface of the rotating transmission shaft 164b. Since this dynamic seal member 164c is the dynamic seal member obtained in (IV) above, it has excellent wear resistance even in a severe underground environment up to a high temperature, for example, about 175 ° C. Can be maintained. The use of such dynamic sealing members is found, for example, in US Patent Application Publication No. 2006/0157283 and US Pat. No. 7,188,685, which are incorporated herein in their entirety. More specifically, FIG. 5 of US 2006/0157283 shows a sealing member 38 on the piston 36 that seals the hole 30 of the biasing device of the rotary variable assembly. U.S. Pat. No. 7,188,685 shows a biasing device.

  The mud motor 166 shown in FIG. 9 is also referred to as a downhole motor, and is a fluid drive motor for rotating the drill bit 162 using the flow force of muddy water as power. The mud motor 166 may be, for example, a mud motor for excursion of well borehole drilling (for well-well drilling applications), and the dynamic seal member of one embodiment of the present invention can be applied. The mud motor 166 is for example a dynamic seal member with high temperature properties up to about 150 ° C. to 200 ° C., a dynamic seal member capable of functioning under extreme wear conditions, or for handling various drilling muds. A dynamic seal member having chemical resistance is required. The conventional dynamic seal member of a mud motor has, for example, insufficient sealing due to expansion of the dynamic sealing member, cracking and dropping of a large fragment of the dynamic sealing member body (chunking phenomenon), insufficient sealing due to wear at high temperature, and movement. There was a tendency for local heating and further degradation of the dynamic seal member due to the wear action of the static seal member. On the other hand, by using the dynamic seal member of one embodiment of the present invention for the dynamic seal member of the mud motor 166, in addition to the characteristics of the dynamic seal member described above, more excellent mechanical characteristics at high temperatures. The above-mentioned problems can be solved by reducing tearing and dropping off, resistance to a wide range of drilling fluids due to excellent chemical resistance, and reduction of locally heated portions due to better thermal conductivity. The mud motor 166 has a cylindrical casing 166a, a tubular stator 166 fixed to the inner peripheral surface of the casing 166a, and a rotor 166c rotatably disposed inside the stator 166d. On the inner peripheral surface 166d of the stator 166b, for example, five spiral grooves extend from the rotary operation system 164 side to the measuring module 168 side during excavation. As the stator 166b, the dynamic seal member according to the embodiment of the present invention obtained in the above (IV) can be used. For example, the outer peripheral surface 166e of the metal rotor 166c has, for example, four spirally protruding threads and is disposed along the groove of the inner peripheral surface 166d of the stator 166b. The inner peripheral surface 166d of the stator 166b and the outer peripheral surface 166e of the rotor 166c are partly in contact as shown in FIG. 9, and a flow path for flowing muddy water is formed in the gap 166f between the inner peripheral surface 166d and the outer peripheral surface 166e. . When the muddy water flowing through the gap 166f and the outer peripheral surface 166e of the rotor 166c come into contact with each other, the rotor 166c can eccentrically rotate in the stator 166b, for example, in the direction of the arrows in FIGS. At this time, since the inner peripheral surface 166d of the stator 166b and the outer peripheral surface 166e of the rotor 166c are in contact with each other and rotate eccentrically by muddy water, the inner peripheral surface 166d of the stator 166b functions in the same manner as a so-called dynamic seal member. . Therefore, since the wear resistance is excellent even in the harsh underground environment as described above, the rotor 166c of the mud motor 166 can be driven to rotate for a long time. In the present embodiment, the mud motor 166 has been described as the fluid drive motor. However, the fluid drive motor can be applied to other fluid drive motors that have the same structure and are driven using a fluid. The rotor may be formed of the dynamic seal member obtained in the above (IV), and the stator may be formed of, for example, metal. The use of such dynamic sealing members is found, for example, in US Patent Application Publication No. 2006/0216178 and US Pat. No. 6,604,922, which are incorporated herein in their entirety. More specifically, FIG. 3 of US 2006/0216178 shows a sealing member as an elastomeric stator (lining) that seals the rotor and generates drilling torque on the rotor. The mud flows between the stator and the rotor. FIG. 4 also shows a seal member as an elastomer sleeve attached to the rotor, which seals the stator. Similarly, FIG. 5 shows a sealing member as an elastomer sleeve on a rotor that seals the stator. FIG. 4 of US Pat. No. 6,604,922 shows that the elastic layer of the liner attached to the stator has a sealing function, and this elastic layer functions as a sealing member. Similarly, FIG. 13 shows that the rotor lining made of an elastomer layer has a sealing function, and this elastomer layer functions as a sealing member.

  The during-drilling measurement module 168 includes an unexcavated measurement instrument (not shown) disposed in a chamber 168a provided on a wall of a pipe having a thick wall called a drill collar. The measuring instrument during excavation includes various sensors, for example, measuring bottom hole data such as heading, inclination, bit direction, load, torque, temperature, pressure, etc., and transmitting these measurement data to the ground in real time. Can do.

In the drilling logging module 170, a logging tool (not shown) is disposed in a chamber 170a provided on a wall of a pipe having a thick wall called a drill collar. The logging tool during excavation includes various sensors, for example, can measure specific resistance, porosity, sonic velocity, gamma ray, etc., and acquire physical logging data. Can be transmitted.
The excavation measurement module 168 and the excavation logging module 170 use the dynamic seal member of the embodiment of the present invention obtained in (IV) above in the chambers 168a and 170a in order to protect various sensors from muddy water and the like. be able to.

  As shown in FIG. 10, the exploration of underground resources on the ground surface 155 by the measurement equipment installed in the drilling assembly includes, for example, a platform and derrick assembly 151 disposed above a borehole 156, and a derrick assembly. For example, a well bottom assembly (BHA: bottom hole assembly) 160 is provided as a well logging device arranged in a well 156 constituted by vertical holes and horizontal holes provided underground from 151. The derrick assembly 151 can include, for example, a hook 151a, a rotary swivel 151b, a kelly 151c, and a rotary table 151d. The hole bottom assembly 160 is fixed to the tip of a long drill string 153 extending from the derrick assembly 151, for example. Inside the drill string 153, muddy water is fed from a pump (not shown) via the rotary swivel 151b, and the fluid drive motor of the hole bottom assembly 160 can be driven. Since the hole bottom assembly 160 is basically the same as the logging tool for seabed described with reference to FIGS. 8 to 10, the description thereof is omitted here. The dynamic seal member of the embodiment can be employed. In addition, the hole bottom assembly 160 demonstrates the example which has the drill bit 162, the rotation operation system 164, the mud motor 166, the measurement module 168 during excavation, and the logging module 170 during excavation as one Embodiment. However, it is not limited to this, and can be selected and combined according to the logging application.

  The oil field application is not limited to the logging device. For example, the dynamic seal member of one embodiment of the present invention can be applied to a downhole tractor used for wireline logging. An example of such a downhole tractor is Schlumberger MaxTRAC or TuffTRAC (both are trademarks of Schlumberger). Such a downhole tractor requires a reciprocating seal member having high wear resistance at a maximum of about 175 ° C. for long-term operation and reliability.

  Previous dynamic seal members required a high degree of polishing on the surface of the sealing piston in the downhole tractor. By polishing the dynamic seal member in this way, it has led to a high yield on the surface of the piston or cylinder that has been mirror-finished during manufacture. The conventional dynamic seal member made of ordinary elastomer has been worn, leaked, reduced in the life of the equipment, and failed. The dynamic seal member may be used at a high sliding speed of up to 2000 ft / hour. Dynamic seals used in downhaul tractors are either in the presence of hydraulic oil on either side or in the presence of hydraulic oil on one side and possibly mud or fluid containing particles on the other side. Need to work. In tractor work, the sliding dynamic seal member needs to function sufficiently over a sliding distance larger than the towing distance. For example, in a 10,000 foot tractor operation, the dynamic seal member is required to function reliably over a cumulative sliding distance of up to 20,000 feet. Further, the dynamic seal member will typically experience a differential pressure of up to 200 psi.

  On the other hand, by using the dynamic seal member of one embodiment of the present invention for a downhole tractor, the above-described problems can be solved by the characteristics of the above-described dynamic seal member. In particular, the processing on the surface of the sealing piston and the cylinder is eased, and the manufacturing cost can be reduced. Excellent wear resistance also helps with a longer life and reliable sealing function. Further, a long life is possible due to low friction.

  The use of such dynamic sealing members is found, for example, in US Pat. No. 6,179,055, which is incorporated herein in its entirety. More specifically, FIGS. 9A and 10A of this US patent show a seal member on the piston. The same applies to FIGS. 9B, 10B and 12 of this patent. FIGS. 15, 12, and 16B of this patent show a sealing member on the piston that seals the tubing and housing. FIG. 16B of this US patent also shows a seal member on the rod.

  In addition, as an oil field application, for example, the dynamic sealing member of the embodiment of the present invention can be applied to formation testing and reservoir fluid sampling tools. Such devices include, for example, Schlumberger's Modular Formation Dynamics Tester (MDT: Trademark of Schlumberger). Such geological inspection and reservoir fluid sampling devices require dynamic seal members with high wear resistance in pump-out modules and other pistons. Also, geological inspection and reservoir fluid sampling instruments require dynamic seal members with high wear resistance and high temperature properties up to about 210 ° C. to seal wells.

  In the past, the dynamic seal member has a large number of reciprocating movements in the piston of the displacement unit of the pump-out module, which moves, extracts and supplies the oil reservoir fluid, sampling, instrument operation, I was doing analysis. Conventional piston dynamic seal members using conventional dynamic seal members tend to wear out and fail after a limited life. This problem was noticeable at higher temperatures. Also, the presence of particles in the fluid accelerated the wear and breakage of the dynamic seal member.

  On the other hand, by using the dynamic seal member of one embodiment of the present invention for the formation inspection and the oil reservoir fluid sampling device, the above-mentioned problems can be solved by the characteristics of the above-mentioned dynamic seal member. In particular, a dynamic seal member having high wear resistance at high temperatures can improve the life. A dynamic seal member having low friction can reduce wear and improve life. In addition, a dynamic seal member having high mechanical properties at high temperatures can improve life and reliability. Furthermore, dynamic seal members with high chemical resistance can also be used to expose oil wells and fluids at high temperatures.

  The use of such dynamic sealing members is found, for example, in US Pat. No. 6,058,773 and US Pat. No. 3,653,436, which are incorporated herein in their entirety. More specifically, FIG. 2 of US Pat. No. 6,058,773 shows a reciprocating seal member on a shuttle piston in a transfer unit (DU) provided in a pump-out module. FIGS. 2, 3, and 4 of US Pat. No. 3,653,436 show an elastomeric member that seals the surface of a well lined with a mud cake.

  In addition, as an oil field application, for example, in-situ fluid sampling bottles and in-situ fluid analysis and sampling bottles also include dynamic seal members according to an embodiment of the present invention. Can be applied. Such equipment can be used, for example, for geological inspection and oil reservoir fluid sampling equipment and wireline logging. Such in-situ fluid sampling bottles and in-situ fluid analysis / sampling bottles require a dynamic seal member that allows high pressure use at low and high temperatures. In addition, such in-situ fluid sampling bottles and in-situ fluid analysis / sampling bottles require a dynamic seal member with high chemical resistance when exposed to various fluids produced. Further, such in-situ fluid sampling bottles and in-situ fluid analysis / sampling bottles require a dynamic seal member that is gas resistant.

In such in-situ fluid sampling bottles and in-situ fluid analysis / sampling bottles, the oil reservoir fluid has been recovered at the oil reservoir conditions in the field having high pressure and high temperature. When these bottles were recovered to the surface, the pressure remained high although the temperature decreased. After collection, the sample was transferred to another storage, transportation or analysis container. The dynamic sealing member on the sliding piston in the sample bottle was responsible for the important functions described below during sample collection as well as during sample transport. For example, due to loss of sample in the deep sea area when high-pressure and low-temperature sealing is not possible when recovering to the surface, loss of sample on the surface at the time of recovery, chemical incompatibility with the sample, and poor sealing caused by expansion due to gas absorption Loss of sample, gas-absorbing dynamic seal member expands, increasing piston friction and drag, over-expansion of the dynamic seal member causes sticking and transfer as the sample is transferred from the bottle to another storage location or analyzer There have been problems such as insufficient sealing or other problems, and multiple sample bottles being used in layers during work. Loss of sample on the surface at the time of recovery could lead to some problems, especially when the sample contains substances such as H ₂ S, CH ₄ , CO ₂ .

  On the other hand, by using the dynamic seal member of one embodiment of the present invention for the in-situ fluid sampling bottle and the in-situ fluid analysis / sampling bottle, in addition to the characteristics of the above-described dynamic seal member, high gas resistance The above-mentioned problems can be solved by achieving high chemical resistance and excellent low temperature sealing performance while satisfying the high pressure and high temperature required characteristics.

  The use of such dynamic seal members is described, for example, in US Pat. No. 6,058,773, US Pat. No. 4,860,581, and US Pat. See 544 (brown et al.). More specifically, FIG. 7 of US Pat. No. 6,058,773 shows a sealing member on a piston in a sample bottle. The two bottle configuration in FIG. 2 of US Pat. No. 4,860,581 shows a sealing member on a piston in the sample bottle. FIG. 1 of US Pat. No. 6,467,544 shows a seal valve.

  In addition, as an oil field application, for example, the dynamic seal member of one embodiment of the present invention can be applied to an in situ fluid analysis tool (IFA). Such an in-situ fluid analysis instrument requires a dynamic seal member with high wear and gas resistance for downhole PVT. PVT means analyzing pressure, volume, and temperature. The in-situ fluid analysis instrument also requires a dynamic seal member with high chemical resistance for handling the produced fluid. Furthermore, the in-situ fluid analysis instrument requires a flow line fixed dynamic seal member with high pressure, high temperature properties up to about 210 ° C. and high gas resistance. A flow line is an area exposed to sampled fluid.

  In-situ fluid analyzers, for example, in downhole PVT, needed to collect oil reservoir fluid samples, reduce pressure to initiate gas generation and determine bubble points. The depressurization was very rapid, for example, over 3000 psi / min, and a sudden depressurization could occur in a dynamic seal member connected directly to the PVT sample chamber. The dynamic seal member had to be able to withstand over 200 PVT cycles. In addition, the dynamic seal member for downhole PVT sometimes fails to function due to the gas due to sudden pressure reduction. Therefore, the downhole PVT cannot be performed at 210 ° C. with a conventional commercially available dynamic seal member. In the conventional dynamic seal member, in the flow line, a defect due to expansion and water bubble formation due to gas permeation may occur.

  On the other hand, the above-described problems can be solved by using the dynamic seal member according to the embodiment of the present invention for the in-situ fluid analysis instrument. A dynamic seal member having excellent mechanical properties at high pressure and high temperature can reduce the expansion tendency. A dynamic seal member in which voids in the dynamic seal member are reduced by the carbon nanofibers can improve gas resistance. By improving the material properties of the dynamic seal member, it is possible to improve resistance to expansion and sudden pressure reduction. A dynamic seal member with excellent chemical resistance can improve chemical resistance against a wide range of output fluids.

  The use of such dynamic seal members is described, for example, in US Patent Application Publication No. 2009/0078412, US Pat. No. 6,758,090, US Pat. No. 4,782,695, which is incorporated herein in its entirety. And in US Pat. No. 7,461,547. More specifically, FIG. 7 of US 2009/0078412 shows a seal member on a valve and FIG. 5 shows a seal member on a piston seal device. FIG. 21a of US Pat. No. 6,758,090 shows a seal member on the valve and piston. U.S. Pat. No. 4,782,695 shows a seal member between a needle and a PVT processing chamber. U.S. Pat. No. 7,461,547 shows a seal member on a valve for isolating fluid in a PVCU as a seal member of a piston sleeve device in a PVCU (pressure volume control unit) for PVT analysis.

  In addition, as an oil field application, for example, the wire seal logging, logging during drilling, well test, perforation, and all devices used for sampling work, the dynamic seal member of one embodiment of the present invention is used. Can be applied. Such equipment requires a dynamic sealing member that enables high pressure sealing at low and high temperatures, for example.

  For example, such a device requires a dynamic seal member that functions in a wide temperature range from a low temperature to a high temperature for use in the deep sea. When the dynamic seal member does not function normally at a low temperature, There was a possibility of leakage into the air chamber and equipment failure. Further, in sampling in a cold water region such as the deep sea region or the North Sea, the dynamic seal member has to function in a wide temperature range from a low temperature to a high temperature. This is because, in such a water area, the sample collected in the ground is hot, but the temperature of the sample carried to the ground surface decreases to the ground surface temperature. For example, when the dynamic sealing member is not sufficiently sealed at high pressure and low temperature, there is a possibility that sample leakage or loss and other problems may occur. Many of these devices are filled with hydraulic oil and pressurized to 100-200 psi, so oil leakage occurs in cold surface conditions when not using a dynamic seal member that functions well at low temperatures. Or there may be a problem when recovering from the deep sea at low temperature.

  On the other hand, by using the dynamic seal member of one embodiment of the present invention in such a device, in addition to the characteristics of the dynamic seal member described above, excellent low temperature sealing performance, better mechanical properties at high temperature The above problems can be solved by the excellent hermeticity at high pressure and high temperature due to the characteristics.

  Moreover, as an oil field use, the dynamic sealing member of one Embodiment of this invention is applicable also to a side wall coring tool (Side wall Coring Tool), for example. Such a side wall coring device has, for example, a dynamic seal member having low friction and high wear resistance, a dynamic seal member having a long life and high sealing reliability, and a high temperature characteristic of about 200 ° C. at the maximum. A dynamic seal member or a dynamic seal member having a delta P of 100 psi or less (low speed sliding) is required. Here, delta P is a pressure difference between both sides of the dynamic seal member of the piston. For example, when the dynamic seal member has low friction, the delta P becomes small, that is, the piston can be moved with a small pressure difference. Indicates.

  Such a side wall coring apparatus may stop coring, for example, when a dynamic sealing member brings about sticking or an increase in frictional force. In the drilling of each core, it was required to rotate and slide the drill bit by engaging with a dynamic seal member while cutting the formation. Furthermore, in order to maintain a high core excavation efficiency, low sealing friction in the dynamic seal member was important.

  On the other hand, by using the dynamic seal member of one embodiment of the present invention in such a device, the above-described problems are solved by the following characteristics in addition to the characteristics of the dynamic seal member described above. Can do. A low-friction dynamic seal member can reduce power consumption for core drilling operations and actuation / movement. In addition, the low-friction dynamic seal member can reduce the tendency of sticking and rolling and improve the efficiency of core excavation work. Furthermore, the dynamic seal member having high wear resistance can improve the sealing life in a wearable fluid.

  The use of such dynamic seal members is described, for example, in US Patent Publication No. 2009/0133932, US Pat. No. 4,714,119, and US Pat. No. 7,191,831, which are incorporated herein in their entirety. Seen in the issue. More particularly, FIGS. 4 and 5 of US Patent Publication No. 2009/0133932 show a seal member on a coring bit of a coring assembly driven by a motor. FIGS. 3B, 7 and 8 of U.S. Pat. No. 4,714,119 show a seal member on a drill bit that is driven to mine a core from a borehole by a motor at up to 2000 rpm. FIGS. 2A and 2B of US Pat. No. 7,191,831 show a seal member between a coring bit and a coring assembly driven by a motor, and FIG. 3 and FIG. High efficiency can be achieved by using a low friction seal member such as the seal member of the present embodiment between the boundary or the bit of FIG. 8B and the housing.

  Further, as an oil field application, for example, a telemetry / power generation tool for drilling application (Telemetry and power generation tool in Drilling applications) can also apply the dynamic sealing member of one embodiment of the present invention. Such telemetry / power generation equipment includes, for example, a rotary dynamic seal member having high wear resistance, a rotary / slide seal member having low friction, and a dynamic seal member having a high temperature characteristic of about 175 ° C. at the maximum. I need.

  Such a telemetry / power generation device, for example, a mud pulse telemetry device as disclosed in U.S. Pat. No. 7,083,008, uses a rotary dynamic seal member to pierce the interior of a device filled with oil. Protection from fluids (drilling mud) was required. However, since the well fluid contains particles, there is a tendency for wear and tear of the dynamic seal member to increase. In addition, due to insufficient sealing due to wear and wear of the dynamic seal member, there is a possibility that equipment failure occurs when muddy water enters. In addition, the telemetry and power generation device disclosed in US Pat. No. 7,083,008 operates using a sliding dynamic seal member on the piston that compensates the internal hydraulic pressure with an external fluid, Due to wear, wear, expansion, and sticking of the seal member, there is a possibility that a failure of the device due to intrusion of an external fluid may occur.

  On the other hand, by using the dynamic seal member of one embodiment of the present invention for telemetry / power generation equipment, in addition to the characteristics of the dynamic seal member described above, the wear resistance and low friction property of the dynamic seal member are reduced. Improvements can solve the above-mentioned problems by providing a more reliable operation and a longer seal life.

  The use of such dynamic sealing members is found, for example, in US Pat. No. 7,083,008, which is incorporated herein in its entirety. More specifically, FIG. 2 of US Pat. No. 7,083,008 shows a rotary dynamic seal member in a dynamic seal member / bearing assembly between rotors, and FIG. 3a shows oil and well fluid in a pressure compensation chamber. Fig. 9 shows a sliding dynamic seal member on a compensating piston separating (mud).

  Further, as an oil field application, for example, the dynamic seal member of one embodiment of the present invention is also applied to an inflation packer used to isolate a part of a well for sampling and geological survey. can do. The dynamic seal member in such an expansion packer needs to have high wear strength and high temperature characteristics in order to enable repeated operations of expansion and contraction at a plurality of positions in the well.

  Since the dynamic seal member in the conventional packer does not have a desired high-temperature characteristic, it has a tendency to deteriorate / decrease in the sealing function. Moreover, the dynamic seal member of the conventional packer has a tendency not to satisfy the desired life.

  On the other hand, by using the dynamic seal member of one embodiment of the present invention for the expansion packer, the dynamic seal member has better wear resistance and higher high temperature characteristics. Reliability can be improved.

  The use of such dynamic seal members is described, for example, in US Pat. No. 7,578,342, US Pat. No. 4,860,581, and US Pat. No. 7,392, which are incorporated herein in their entirety. See in 851. More specifically, FIGS. 1A, 1B, and 1C of US Pat. No. 7,578,342 show that the seal member expands to seal the blast hole and isolate the member indicated at 16. ing. Further, the elastomer seal member (packer member) in FIG. 4A or the members denoted by reference numerals 712 and 812 in FIGS. 7 and 8 indicate the seal members. FIG. 1 of US Pat. No. 4,860,581 shows an expansion packer member that seals a well. U.S. Patent No. 7,392,851 shows an expansion packer member.

  Although the embodiments of the present invention have been described in detail as described above, those skilled in the art can easily understand that many modifications can be made without departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention.

Examples of the present invention will be described below, but the present invention is not limited thereto.
(1) Preparation of carbon nanofibers By means of a catalyst reaction method (Substrate Reaction Method), an average diameter of 15 nm, a frequency maximum diameter of 18 nm, a stiffness index of 4.8, a Raman peak ratio (D / G) of 1.7, a nitrogen adsorption specific surface area A 260 m ² / g multilayer carbon nanofiber (shown as “MWCNT-1” in Table 1) was produced. The manufacturing conditions were as follows. By ultrasonication for 20 minutes in a solution obtained by dissolving 10.0 g of aluminum oxide powder, 0.2 g of ammonium iron citrate and 0.1 g of hexaammonium heptamolybdate tetrahydrate in 300 ml of pure water. Dispersed. Next, this solution was dried at 100 ° C. with stirring to obtain catalyst powder. The catalyst powder was placed in an alumina boat and placed in a tubular electric furnace. The reaction tube of the electric furnace was a quartz tube having an inner diameter of 3 cm and a length of 1.5 m, and the length direction in the central part was 600 mm, and a boat in which catalyst powder was put in the central part of the heating area. After raising the temperature of the electric furnace to 800 ° C. under an argon atmosphere, a mixed gas of ethylene and argon was circulated for 30 minutes to obtain carbon nanotubes having an average diameter of 15 nm. Graphitization of carbon nanofibers is not performed. The carbon nanofiber is a photograph taken with an electron microscope (SEM) at 1.0 kV, 10,000 times to 100,000 times, and is a distance between adjacent defects Lx as a length of a substantially straight portion where the fiber is not bent. The fiber diameter D is measured, and the result is used to calculate the stiffness index at 200 locations for each fiber type by Lx / D, and the stiffness index is divided by the number of measurement locations (200) to obtain the average stiffness The degree index was determined.

Untreated carbon nanofibers having an average diameter of 87 nm were produced by the floating flow reaction method. The manufacturing conditions were as follows. A spray nozzle is attached to the top of a vertical heating furnace (inner diameter 17.0 cm, length 150 cm). The furnace wall temperature (reaction temperature) is raised to and maintained at 1000 ° C., and 20 g / min of a benzene liquid raw material containing 4% by weight of ferrocene is supplied from the spray nozzle at a flow rate of hydrogen gas of 100 L / min. To be sprayed directly. The shape of the spray at this time is a conical side surface (trumpet shape or umbrella shape), and the apex angle of the nozzle is 60 °. Under these conditions, ferrocene is pyrolyzed to produce iron fine particles, which become seeds, which generate and grow carbon nanofibers from the carbon produced by pyrolysis of benzene, and the carbon nanofibers are spaced every 5 minutes. And continuously produced for 1 hour. The untreated carbon nanofibers were heat-treated at 2800 ° C. in a superheated furnace in an inert gas atmosphere to obtain graphitized carbon nanofibers (shown as “MWCNT-3” in Tables 1 and 2). Graphitized carbon nanofiber (MWCNT-5) has an average diameter of 87 nm, a frequency maximum diameter of 90 nm, a stiffness index of 9.9, an average length of 9.1 μm, a surface oxygen concentration of 2.1 atm%, and a Raman peak ratio (D / G) 0.11, a nitrogen adsorption specific surface area of 25 m ² / g, and was a multilayer carbon nanofiber (trade name: VGCF-S) manufactured by Showa Denko KK Carbon nanofibers obtained by subjecting the untreated carbon nanofibers having an average diameter of 87 nm to low temperature heat treatment at 1500 ° C., which is lower than the reaction temperature in the floating flow reaction method, in an inert gas atmosphere (“MWCNT-2” in Table 1). Obtained). Carbon nanofibers (MWCNT-2) heat-treated at low temperature have an average diameter of 87 nm, a frequency maximum diameter of 90 nm, a stiffness index of 9.9, a surface oxygen concentration of 2.1 atm%, a Raman peak ratio (D / G) of 1.12, The nitrogen adsorption specific surface area was 30 m ² / g.

  In addition, in order to improve the handleability in a manufacturing process, the carbon nanofiber (MWNT-2) heat-processed at low temperature was granulated by the roll process. The roll treatment is a roll press machine that is a dry compression granulator having two rolls of carbon nanofibers (roll diameter is 150 mm, rolls are smooth rolls, roll interval is 0 mm, set compression force between rolls (linear pressure) ) 1960 N / cm, gear ratio 1: 1.3, roll rotation speed 3 rpm) and granulated into a plate-like lump (carbon nanofiber aggregate) having a diameter of about 2 to 3 cm. The particle size was adjusted by crushing through a crushing granulator (rotating speed: 15 rpm, screen: 5 mm) having a rotary blade.

  (2) Preparation of carbon fiber composite material samples of Examples 1-6 and Comparative Examples 1-6 As Examples 1-6 and Comparative Examples 2-6, FKM (Tables 1 and 2) were used in a closed kneader Brabender. Then, after adding and masticating, a predetermined amount of carbon nanofibers and carbon black (shown as “MT-CB” in Tables 1 and 2) shown in Tables 1 and 2 are added to FKM. After kneading at a chamber temperature of 150 ° C. to 200 ° C., the first kneading step was performed and the product was taken out from the roll. Further, the mixture was wound around an open roll (roll temperature: 10 to 20 ° C., roll interval: 0.3 mm), and thinning was repeated 5 times. At this time, the surface speed ratio of the two rolls was set to 1.1. Furthermore, the carbon fiber composite material obtained by setting the roll gap to 1.1 mm and passing through was put and dispensed. The separated sheet was compression-molded at 120 ° C. for 2 minutes to obtain uncrosslinked carbon fiber composite material samples of Examples 1 to 6 and Comparative Examples 2 to 6 having a thickness of 1 mm. Further, the carbon fiber composite material obtained by passing through the thin film was mixed with 2 parts by weight of peroxide (indicated as “PO” in Tables 1 and 2) and triallyl isocyanurate (in Tables 1 and 2 as “TAIC”). 1) and Comparative Example 2 having a thickness of 1 mm formed by press vulcanization (170 ° C./20 minutes) and secondary vulcanization (200 ° C./4 hours). ~ 6 sheet-like crosslinked carbon fiber composite material samples were obtained. In Comparative Example 1, neither carbon nanofiber nor carbon black was blended, but the same kneading process was performed.

In Tables 1 and 2, “FKM” is a ternary FKM manufactured by DuPont having a fluorine content of 66 mass%, a Mooney viscosity (ML _{1 + 4} 121 ° C.) of 65, and a glass transition point of −20 ° C. there were.

  In Tables 1 and 2, “MT-CB” was MT grade carbon black having an arithmetic average diameter of 200 nm, and “Austin Black” was carbon black called Austin Black.

(3) Measurement Using Pulsed Method NMR About the uncrosslinked carbon fiber composite material samples of Examples 1 to 6 and Comparative Examples 1 to 6, measurement by the Hahn echo method was performed using pulsed method NMR. This measurement was performed using “JMN-MU25” manufactured by JEOL Ltd. The measurement is carried out under the conditions that the observation nucleus is ¹ H, the resonance frequency is 25 MHz, the 90 ° pulse width is 2 μsec, and the decay curve is measured by the pulse sequence of the Hahn-echo method (90 ° x-Pi-180 ° y). The characteristic relaxation time (T2′HE) at 150 ° C. of the carbon fiber composite material sample was measured. The measurement results are shown in Table 1. Moreover, the measurement by the solid echo method was performed using pulse method NMR. This measurement was performed using “JMN-MU25” manufactured by JEOL Ltd. The measurement is performed under the conditions of an observation nucleus of ¹ H, a resonance frequency of 25 MHz, a 90 ° pulse width of 2 μsec, and an attenuation curve is measured by a pulse sequence (90 ° x-Pi-90 ° y) of the solid echo method. The characteristic relaxation time (T2′SE) at 150 ° C. of the carbon fiber composite material sample was detected. The measurement results are shown in Table 1.

  (4) Measurement of hardness, 50% modulus, 100% modulus, tensile strength, elongation at break, dynamic elastic modulus, compression set, tear strength, tear energy, tensile fatigue life and DIN wear Examples 1-6 and About the carbon fiber composite material sample of the crosslinked body of Comparative Examples 1-6, rubber hardness (Hs (JIS-A)) was measured based on JIS K 6253.

  About the test piece which cut out the carbon fiber composite material sample of the bridge | crosslinking body of Examples 1-6 and Comparative Examples 1-6 in the dumbbell shape of JIS6 type, it was 23 +/- 2 degreeC using the tensile tester by Toyo Seiki Co., Ltd. Tensile strength test was performed based on JIS K6251 at a tensile speed of 500 mm / min (shown as “TB (MPa)” in Tables 1 and 2), and elongation at break (“EB (%) in Tables 1 and 2). ), 50% stress (shown as “M50” in Tables 1 and 2), and 100% stress (shown as “M100” in Tables 1 and 2).

  About the test piece which cut out the carbon fiber composite material sample of the bridge | crosslinking body of Examples 1-6 and Comparative Examples 1-6 into a strip shape (40x1x5 (width) mm), the dynamic viscoelasticity test made from SII company Using a machine DMS6100, a dynamic viscoelasticity test was performed based on JIS K6394 at a distance between chucks of 20 mm, a measurement temperature of −100 to 300 ° C., a dynamic strain of ± 0.05%, and a frequency of 10 Hz, and the measurement temperatures were 25 ° C. and 200 ° C. The dynamic elastic modulus at 0 ° C. (shown as “E ′ (25 ° C.) (MPa)” and “E ′ (200 ° C.) (MPa)” in Tables 1 and 2)) was measured.

  The crosslinked carbon fiber composite material samples of Examples 1 to 6 and Comparative Examples 1 to 6 were cut into test pieces having a diameter of 29.0 ± 0.5 mm and a thickness of 12.5 ± 0.5 mm, and compression set (JIS K6262) was measured. The compression set was performed at 200 ° C. for 70 hours at 25% compression.

  The carbon fiber composite material samples of the crosslinked bodies of Examples 1 to 6 and Comparative Examples 1 to 6 were cut into angle-shaped test pieces without incision of JIS K 6252, and using an autograph AG-X manufactured by Shimadzu Corporation, a tensile speed of 500 mm / Min is measured in accordance with JIS K 6252, the maximum tearing force (N) is measured, and the measurement result is divided by the thickness of the test piece to determine the tearing strength (N / mm). The area surrounded by the load-displacement curve of the tear test was taken as the tear energy, with the measured load (N) on the vertical axis and the stroke displacement (mm) on the horizontal axis on the horizontal axis. The cross-linked carbon fiber composite material samples of Examples 1 to 6 and Comparative Examples 1 to 6 were cut into strip-shaped test pieces of 10 mm × width 4 mm × thickness 1 mm as shown in FIG. A notch with a depth of 1 mm is made from the center of the side in the width direction, and using a TMA / SS6100 testing machine manufactured by SII, in air, 200 ° C., maximum tensile stress 2.5 N / mm or 2.0 N / mm, frequency Tensile with repeated tensile loads under the condition of 1 Hz (0 N / mm to 2.5 N / mm when the maximum tensile stress is 2.5 N / mm, 0 N / mm to 2 N / mm when the maximum tensile stress is 2 N / mm) A fatigue test was performed, and the test piece was broken or the number of tensions up to 1 million was measured. In Tables 1 and 2, the tensile fatigue test indicated as “(a) Tensile fatigue life (times)” is a repeated tensile load (0 N / mm) in the air atmosphere at 200 ° C., maximum tensile stress of 2 N / mm, and frequency of 1 Hz. ˜2 N / mm). In Tables 1 and 2, the tensile fatigue test shown as “(b) Tensile fatigue life (times)” is a repeated tensile load (0 N) in the air atmosphere at 200 ° C., maximum tensile stress 2.5 N / mm, and frequency 1 Hz. / Mm to 2.5 N / mm). In addition, when it did not break even when the number of tensions reached 1 million times, it was described in Tables 1 and 2 as “1 million interruptions”.

Samples of the crosslinked carbon fiber composite materials of Examples 1 and 2 and Comparative Example 4 were cut into a disk-shaped test piece having a diameter of 8 mm and a thickness of 6 mm, and the test piece was rotated at a load of 49.0 N using a 5 kgf weight. The mass (g) of the test piece before and after the wear test was measured in the same manner as the DIN-53516 wear test except that it was pressed against a # 100 disc-shaped grindstone in water at 25 ° C. and the wear distance was 20 m. The amount of wear Wa = (g ₂ −g ₁ ) / (P · L · d) was obtained by calculation and listed as “DIN wear” in Tables 1 and 2. The unit of the wear amount Wa is cm ³ / N · m. The mass of _{g 1} is a front wear test piece (g), the mass of _{g 2} are after the abrasion test specimen (g), P is the weight of the set load (49N), L is the wear length (m), d is Specific gravity (g / cm ³ ).

The crosslinked carbon fiber composite material samples of Examples 1 and 2 and Comparative Example 4 were cut into a disk-shaped test piece having a diameter of 8 mm and a thickness of 6 mm, and based on NACE (National Association of Corrosion Engineers) TM097-97. Place the test piece in a pressure vessel, pressurize at 5.5 (MPa) with CO ₂ fluid at room temperature for 24 hours, and then rapidly depressurize at a depressurization rate of 1.8 (MPa / second), before and after the test. The volume change of the piece was measured. The volume change was calculated by dV (%) = (Va−Vb) · 100 / Vb. Vb is the volume of the test piece before the test, and Va is the volume of the test piece after the test. Here, the volume change dV is the volume expansion after the test, and is a test for evaluating gas resistance, and is described as “volume expansion (%)” in Tables 1 and 2. The volume of the test piece before the test was measured with an electronic hydrometer, specifically, Va = (Wa−Ww) / dt. Similarly, the volume Vb of the test piece after the test was also calculated. Wa is the weight of the test piece in the air before the test, Ww is the weight of the test piece in the water before the test, and dt is the specific gravity of water corrected by the water temperature.
The measurement results are shown in Tables 1 and 2.

  As apparent from the results in Tables 1 and 2, the crosslinked carbon fiber composite material samples of Examples 1 to 6 of the present invention have a higher number of tensile fatigue lives than those of Comparative Examples 1 to 6, and high temperature (200 (° C.). Moreover, it turned out that the carbon fiber composite material sample of the crosslinked body of Example 1, 2 of this invention has a small amount of DIN abrasion compared with the comparative example 4, and is excellent in abrasion resistance. Moreover, it turned out that the carbon fiber composite material sample of the crosslinked body of Example 1, 2 has a small volume expansion compared with the comparative example 4, and is excellent in gas resistance.

2 Open roll 10 First roll 20 Second roll 30 FKM
60 Carbon nanofiber 70 Dry compression granulator 72, 74 roll 80 Carbon nanofiber assembly 100 Test piece 106 Notch 110 Chuck 120 DIN abrasion tester 150 Platform 155 Derrick assembly 160 Hole bottom assembly 162 Drill bit 164 Rotation operation system 166 Mud motor

Claims (17)

For ternary fluorine-containing elastomer (FKM), including carbon nanofibers,
The carbon nanofibers are carbon nanofibers having an average diameter of 10 nm to 20 nm or carbon nanofibers having an average diameter of 60 nm to 110 nm and heat-treated at a low temperature,
Carbon nanofibers which the average diameter was low-temperature heat treatment a 60nm~110nm, the ratio of the peak intensity D of around 1300 cm ^-1 to the peak intensity G of around 1600 cm ^-1 measured by Raman scattering spectroscopy (D / G) Is greater than 0.9 and less than 1.6;
A dynamic seal member having a number of breaks of 10 or more in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2.5 N / mm, and a frequency of 1 Hz. In claim 1,
For 100 parts by mass of the ternary fluorine-containing elastomer (FKM), 0.5 parts by mass to 30 parts by mass of carbon nanofibers having an average diameter of 10 nm to 20 nm and 0 part by mass of filler having an average particle diameter of 5 nm to 300 nm. Part to 50 parts by mass,
The amount of the carbon nanofiber and the filler is a dynamic seal member that satisfies the following formulas (1) and (2).
Wt = 0.09W1 + W2 (1)
5 ≦ Wt ≦ 30 (2)
W1: Blending amount of filler (parts by mass)
W2: Compounding amount (parts by mass) of carbon nanofibers. In claim 1,
Filling of 4 to 30 parts by mass of carbon nanofibers having an average diameter of 60 nm to 110 nm and low-temperature heat treatment, and an average particle diameter of 5 to 300 nm with respect to 100 parts by mass of the ternary fluorine-containing elastomer (FKM) 0 parts by mass to 60 parts by mass of an agent,
The amount of the carbon nanofiber and the filler is a dynamic seal member that satisfies the following formulas (3) and (4).
Wt = 0.1W1 + W2 (3)
10 ≦ Wt ≦ 30 (4)
W1: Blending amount of filler (parts by mass)
W2: Compounding amount (parts by mass) of carbon nanofibers. In any one of Claims 1-3,
The dynamic seal member has a hardness of less than 80;
A dynamic seal member having a fracture number of 50 or more in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2 N / mm, and a frequency of 1 Hz. In any one of Claims 1-3,
The dynamic sealing member has a hardness of 80 or more,
A dynamic seal member having a number of breaks of 300 or more in a tensile fatigue test at 200 ° C., a maximum tensile stress of 2 N / mm, and a frequency of 1 Hz. In any one of Claims 1-5,
Wear amount Wa in the high-pressure wear test 25 ° C. is ^{0.010cm 3 / N · m~0.070cm 3 /} N · m,
The wear amount Wa is a dynamic seal member that satisfies the following formula (5).
Wa = (g ₂ −g ₁ ) / (P · L · d) (5)
g ₁ : Mass of the test piece before wear (g)
g ₂ : Mass of the test piece after wear (g)
P: Set weight of weight (N)
L: Wear distance (m)
d: Specific gravity (g / cm ³ ). In any one of Claims 1-6,
The dynamic seal member is a dynamic seal member used in an oil field device. In claim 7,
The oil field device is a dynamic seal member that is a logging device that performs logging in a well. In claim 7,
The dynamic seal member is an endless dynamic seal member disposed in the oil field device. In claim 7,
The dynamic seal member is a stator of a fluid drive motor disposed in the oil field device. In claim 10,
The dynamic seal member, wherein the fluid drive motor is a mud motor. In claim 7,
The dynamic seal member is a rotor of a fluid drive motor disposed in the oil field device. In claim 12,
The dynamic seal member, wherein the fluid drive motor is a mud motor. In any one of Claims 1-13,
The ternary fluorine-containing elastomer (FKM) has a fluorine content of 66 to 70 mass%, a median value of Mooney viscosity (ML _{1 + 4} 121 ° C.) of 25 to 65, and a glass transition point of 0 ° C. or less. Sealing member. In any of the claims 1-14,
Before the carbon nanofiber is blended with the ternary fluorine-containing elastomer (FKM), rigidity = Lx ÷ D (Lx: distance between adjacent defects of the carbon nanofiber, D: Dynamic sealing member having an average value of stiffness defined by (D: diameter of carbon nanofiber) of 3 to 12.

In claim 2 or 3,
The dynamic sealing member, wherein the filler is carbon black having an average particle diameter of 10 nm to 300 nm. In claim 2 or 3,
The dynamic sealing member, wherein the filler has an average particle diameter of 5 nm to 50 nm and is at least one selected from silica, talc and clay.

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