JP2011179596A - Seal packing material for flanged pipe joint and connection method of pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal packing material for a flanged pipe joint having excellent sealing property for a flanged pipe joint for connecting pipes each having a flanged pipe joint together in a fluid-tight manner, and a connection method of pipes. <P>SOLUTION: In the method for connecting the seal packing material 2 for a flanged pipe joint is formed by molding a self-adhesive silicone rubber composition with pipes 11 and 21 having flanged pipe joints 13 and 23, the first pipe 11 and the second pipe 21 having the flanged pipe joints 13 and 23 are arranged so that the flanged pipe joints 13 and 23 face each other, the seal packing material 2 for a flanged pipe joint formed by molding the self-adhesive silicone rubber composition is arranged between the flanged pipe joints 13 and 23; the flanged pipe joints 13 and 23 are fastened together by a fastener 31 to compress the seal packing material 2 for a flanged pipe joint; and the pipes 11 and 12 are connected together by curing the seal packing material 2 for a flanged pipe joint. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a seal packing material for brazed pipe joints and a method for connecting pipes. More specifically, the sealing performance of brazed pipe joints is excellent, and pipes having brazed pipe joints are connected in a liquid-tight state. The present invention relates to a seal packing material for a flanged pipe joint and a pipe connecting method.

  As a method of connecting pipes having brazed pipe joints at their ends, a gasket is interposed between the brazed pipe joints arranged so as to face each other, and the brazed pipe joints are fastened with a fastener. The method of doing is mentioned. The packing used in this method is formed in the shape of the brazed pipe joint from, for example, metal, rubber, or resin, and is compressed by the brazed pipe joint in a state where the pipe is connected. Examples of the rubber include EPDM and fluororubber.

  As a packing used for connecting pipes, for example, Patent Document 1 states that “the innermost edge of a joint bolt insertion hole that is smaller than the diameter of a circumscribed circle connecting the outermost edges of the joint bolt insertion hole in the flange and that is in the flange. A ring-shaped flat packing having an outer edge diameter larger than the diameter of the inscribed circle connecting the two, and a chip having a size that allows the joining bolt to be inserted is provided at a position corresponding to the joining bolt insertion hole in the flange. Is described.

  When vibration is transmitted from the outside to the pipes connected as described above, in particular, when the stress is applied from the outside, the tightening force applied to the packing compressed with a uniform tightening force is reduced. The packing may be deformed and the fluid flowing in the pipe may leak from a gap formed between the brazed pipe joint. In particular, when vibration, stress, and the like increase, the deformation of the packing also increases and fluid leakage becomes significant.

  Further, in the connection method, when the brazed pipe joints are not fastened with a uniform fastening force, for example, when the fastener is in a so-called “single-tightened” state, the packing and the brazed pipe joint A gap is gradually formed between them, and the fluid flowing through the pipe may leak out.

JP 2009-204138 A

  The present invention provides a seal packing material for brazed pipe joints and a method for connecting pipes, which are excellent in sealability of brazed pipe joints and can connect pipes having brazed pipe joints in a liquid-tight state. And aim.

As means for solving the problems,
Claim 1 is a seal packing material for a brazed pipe joint formed by molding a self-adhesive silicone rubber composition,
Claim 2 is the seal packing material for a brazed pipe joint according to claim 1, wherein the self-adhesive silicone rubber composition is molded into a ring shape or a band shape.
Claim 3 is a method of connecting a pipe having a brazed pipe joint, wherein the first pipe and the second pipe having a brazed pipe joint are arranged so that the brazed pipe joints face each other, A brazed pipe joint seal packing material formed by molding a self-adhesive silicone rubber composition between the brazed pipe joints is inserted, and the brazed pipe joints are fastened with a fastener to form the brazed pipe joint. This is a pipe connection method in which the seal packing material is compressed and the brazed pipe joint seal packing material is cured.

  Since the seal packing material for brazed pipe joints according to the present invention is formed by molding a self-adhesive silicone rubber composition, each of the brazed pipe joints in a compressed state in conformity with the fastening state of the brazed pipe joint. Adhesive to, exhibit high sealing performance between brazed pipe joints.

  Further, in the pipe connection method according to the present invention, the brazed pipe joint seal packing material according to the present invention is inserted between the brazed pipe joints, and the brazed pipe joint is fastened and cured. The joint seal packing material can be bonded to each brazed pipe joint in a compressed state so as to match the fastening state of the fastener, and high sealability between the brazed pipe joints can be ensured.

  Therefore, according to the present invention, there is provided a seal packing material for brazed pipe joints and a pipe connecting method that are excellent in sealing performance of brazed pipe joints and that can connect pipes having brazed pipe joints in a liquid-tight state. Can be provided.

FIG. 1 is a view showing an example of a seal packing material for a flanged pipe joint according to the present invention. FIG. 2 is an explanatory view showing a state in which two pipes are connected by the pipe connecting method according to the present invention.

  The seal packing material for a brazed pipe joint according to the present invention is used in a method for connecting or fastening brazed pipe joints of pipes having a brazed pipe joint, specifically, by using a self-adhesive silicone rubber composition. A member formed by molding an object.

  In the present invention, the “seal packing material” means a molded body before curing that becomes a seal packing, but in some cases, it may mean a seal packing itself formed by curing the molded body. In the present invention, the “seal packing” is also simply referred to as a packing or a packing seal. In the present invention, “鍔” is also referred to as a flange, and usually means an outward flange protruding in a ring shape toward the radially outer side of the pipe.

  The seal packing material for brazed pipe joints according to the present invention is formed into various shapes. For example, the seal packing material for a flanged pipe joint according to the present invention is formed into a ring shape, a disk shape, a semicircular plate shape, an elliptical plate shape, a semielliptical plate shape, a band shape, a string shape, or the like. The seal fitting material for a flanged pipe joint may have, for example, a through hole drilled at a position corresponding to an insertion hole through which a bolt or the like of a fastener drilled in the collar is inserted. The seal packing material for a brazed pipe joint according to the present invention is preferably formed into a flat shape with a smooth surface, but may be an uneven surface that matches the surface shape of the brazed pipe joint. The seal packing material for a brazed pipe joint according to the present invention may have a single-layer structure or a multi-layer structure.

  The seal packing material for a flanged pipe joint according to the present invention is adjusted to a size that does not impede the flow of the fluid flowing through the inside of the pipe to be connected. And an outer diameter equal to or smaller than the outer diameter of the flange. Therefore, the seal packing material for a flanged pipe joint according to the present invention has the same or smaller width than the width of the flange, that is, the difference between the outer diameter and the inner diameter of the flange. The thickness of the seal packing material for the brazed pipe joint is appropriately adjusted according to the brazed pipe joint to be connected, and is selected from a range of, for example, 1 to 5 mm, and a large vibration is transmitted to the connecting portion or is large. When stress or the like is applied, the thickness is made relatively thick, about 2 to 5 mm.

  The pipe connected by the seal packing material for a brazed pipe joint according to the present invention is a pipe having a brazed pipe joint at its end, and a liquid such as water, oil, a refrigerant and a heat medium, Or it is a pipe | tube with which gas, such as air, water vapor | steam, and an inert gas distribute | circulates. Such a pipe includes, for example, a pipe main body and a brazed pipe joint formed at the end of the pipe main body, and the brazed pipe joint may be formed of only a brim. It may be an inflatable portion that is provided continuously from the end of the main body and gradually expands toward the end, and a brazed pipe joint having a flange on the end surface of the inflatable portion. As an example in which the flanged pipe joint is formed only from the hook, for example, pipes 11 and 21 shown in FIG. The dimensions of such a tube are not particularly limited, and are appropriately adjusted according to the fluid, application, and the like. There are no particular limitations on the conditions under which the fluid flows in the pipe, for example, the type of fluid, the flow pressure, the flow rate, the temperature, and the like.

  The pipe connected with the seal packing material for a brazed pipe joint according to the present invention is, for example, a pipe forming various pipes for home use, factory use, building use, etc., or a pipe used for the various pipes, for example, Water pipes, drain pipes, fuel pipes, air ducts, waste discharge pipes and the like can be mentioned. The pipes connected by the seal packing material for brazed pipe joints according to the present invention form various pipes that are disposed in locations, applications, and devices where vibrations from the outside are transmitted or stress from the outside is applied. A pipe or a pipe used for various pipes provided in a position, application, and apparatus to which vibration from the outside is transmitted or stress from the outside is applied is preferable.

  A seal packing material for brazed pipe joints (hereinafter simply referred to as a seal packing material) 1 which is an example of a seal packing material for brazed pipe joints according to the present invention is shown in FIG. Further, the self-adhesive silicone rubber composition is formed into a flat flat shape in the form of a single layer ring. The seal packing material 1 is adjusted to a size that matches the size of the flange to be inserted. Specifically, the outer diameter is not more than the outer diameter of the flange, the inner diameter is not less than the inner diameter of the flange, and the thickness is It is set to about 2 mm.

  FIG. 1B shows a seal packing material for brazed pipe joints (hereinafter sometimes simply referred to as a seal packing material) 2, which is another example of the seal packing material for brazed pipe joints according to the present invention. As shown in the figure, the self-adhesive silicone rubber composition is formed into a flat flat shape in the form of a single layer ring, and eight through holes 2a through which bolts of fasteners are inserted are formed at equal intervals in the circumferential direction. Being done. Each of the through holes 2 a has a circular shape, and the center thereof is disposed at the substantially radial center of the seal packing 2. The seal packing material 2 is adjusted to a size suitable for the size of the flange of the flanged fitting to be inserted. Specifically, the outer diameter is equal to or smaller than the outer diameter of the flange, and the inner diameter is equal to or larger than the inner diameter of the flange. Yes, the thickness is set to about 2 mm. Each of the through holes 2a has a diameter that is equal to or larger than the outer diameter (crest diameter) of the bolt and smaller than the difference between the outer diameter and the inner diameter of the seal packing 2.

  FIG. 1 (c) shows a seal packing material for a brazed pipe joint (hereinafter sometimes simply referred to as a seal packing material) 3, which is still another example of the seal packing material for a brazed pipe joint according to the present invention. As shown in the drawing, the self-adhesive silicone rubber composition is formed into a flat, flat layer of a single layer extending linearly. The seal packing material 3 is adjusted to a size suitable for the size of the flange of the flanged fitting to be inserted. Specifically, the width or thickness is equal to or less than the outer diameter of the flange, and the inner diameter is the inner diameter of the flange. The thickness or width is set to about 2 mm.

The self-adhesive silicone rubber composition capable of forming a seal packing material for brazed pipe joints according to the present invention has self-adhesiveness. Self-adhesive refers to the property of adhering to or sticking to a member in which the self-adhesive silicone rubber composition is interposed or disposed with its own adhesive force. In order for the self-adhesive silicone rubber composition to exhibit self-adhesiveness, there may be mentioned a case where the silicone rubber composition contains an adhesive silicone rubber or an adhesive component. In the present invention, the self-adhesive silicone rubber composition only needs to have self-adhesiveness, and the adhesive strength is not particularly limited, and is appropriately determined according to the dimensions and applications of the pipes to be joined. For example, the self-adhesive property includes a tensile strength after curing of the self-adhesive silicone rubber composition of 8 kgf / cm ² or more. The tensile strength can be measured according to JIS K6251. That is, a 2 mm thick sheet of a self-adhesive silicone rubber composition was prepared using two rolls sufficiently cooled in an environment of 23 ° C. and 10% RH, and this sheet was prepared in an atmosphere of 23 ° C. and 50%. Using the cured product obtained after curing for 2 weeks, a “No. 3 dumbbell test piece” described in JIS K6251 was prepared, and the tensile strength (N / mm) was measured under a tensile speed of 500 mm / min. ² ).

  The self-adhesive silicone rubber composition can be molded into a desired shape and retains the shape after molding. In other words, the self-adhesive silicone rubber composition has no fluidity and has a characteristic of being deformed by compression. Specifically, the self-adhesive silicone rubber composition preferably has a Williams plasticity (25 ° C.) of 150 to 450, and particularly preferably 150 to 350. When the Williams plasticity is within the above range, it is easily deformed by compression, so that it conforms to the inserted or arranged member and is excellent in adhesion with these, and exhibits high adhesive strength. The shape after molding can be maintained over a long period of time. The Williams plasticity is measured according to JIS K6249: 1997 (Testing method for uncured and cured silicone rubber). That is, in an environment of 25 ° C., 2 g of a self-adhesive silicone rubber composition was used as a spherical test piece, and the test piece was sandwiched between cellophane papers, and a parallel plate plasticity meter with a dial gauge (“Williams manufactured by Ueshima Seisakusho” Set in a plastometer "), apply a 5 kg load and let stand for 3 minutes, then read the dial gauge scale to millimeters, record the thickness of the specimen, multiply this number by 100 and increase the Williams plasticity And

  As the self-adhesive silicone rubber composition having such characteristics, for example, an addition-curable silicone rubber composition containing an adhesive silicone rubber, or a condensation-curable silicone containing an adhesive silicone rubber A rubber composition etc. are mentioned. The self-adhesive silicone rubber composition is preferably the condensation curable silicone rubber composition in consideration of workability.

  The addition-curable silicone rubber composition contains A) an organopolysiloxane containing at least two alkenyl groups and B) an organohydrogenpolysiloxane having at least two hydrosilyl groups, and is cured by an addition reaction. Any silicone rubber composition may be used, and examples thereof include a silicone rubber composition described in JP-A-2004-315571 (hereinafter sometimes referred to as a silicone rubber composition).

  The silicone rubber composition comprises A) an organopolysiloxane containing at least two alkenyl groups, B) an organohydrogenpolysiloxane having at least two hydrosilyl groups, C) a hydrosilylation catalyst, and D) packing. An addition-curing silicone rubber composition containing at least one agent, wherein 2 mol% or more of all substituents bonded to silicon atoms of the organopolysiloxane after curing are substitutions having 2 or more carbon atoms other than fluoroalkyl groups Alternatively, the silicone rubber composition is an unsubstituted monovalent hydrocarbon group.

  The silicone rubber composition preferably contains, in addition to the components A) to D), an E) adhesion imparting component that imparts and improves adhesiveness as desired. E) As an adhesion imparting component, for example, a silane coupling agent and a partial hydrolyzate thereof, an epoxy group, an acid anhydride group, an organic compound having an α-cyanoacryl group, and a siloxane compound containing these groups, or And organic compounds or siloxane compounds having both of these groups and alkoxysilyl groups or hydrosilyl groups; titanium compounds such as titanium coupling agents and titanates. E) The adhesion-imparting component preferably contains 0.01 to 10 parts by mass with respect to 100 parts by mass of the A) organopolysiloxane.

  In addition to the components A) to D), the silicone rubber composition includes, for example, fumed titanium oxide, carbon black, diatomaceous earth, iron oxide, aluminum oxide, aluminosilicate, zinc oxide, aluminum hydroxide, and the like. You may contain the filler etc. for assign | providing functions, such as a conductive property, heat conductivity, a flame retardance, etc., such as the filler which processed the surface of the filler with the said organosilicon compound.

  This silicone rubber composition is cured by an addition crosslinking reaction at room temperature or a temperature higher than room temperature, and becomes a rubber elastic body. Curing of the silicone rubber composition is almost completed, for example, at 23 ° C. for 7 days.

  The condensation curable silicone rubber composition includes a diorganopolysiloxane having a hydroxyl group or hydrolyzable group bonded to at least two silicon atoms in the molecule, and a silane having two or more hydrolyzable groups in one molecule. Or a partially hydrolyzed silicone rubber composition that cures by a condensation reaction. For example, a curable regular silicone rubber composition described in JP-A No. 2004-175959 (hereinafter, curable regular form). May be referred to as a silicone rubber composition).

  This curable regular silicone rubber composition is based on diorganopolysiloxane having a hydroxyl group or hydrolyzable group bonded to at least two silicon atoms in the molecule, and two hydrolyzable groups in one molecule. Condensation-curable silicone rubber composition containing silane or a partial hydrolyzate thereof having 2 or more mol% of all substituents bonded to silicon atoms of diorganopolysiloxane as a base polymer. A curable regular silicone rubber composition having two or more substituted or unsubstituted monovalent hydrocarbon groups, shaped into a fixed shape before curing and having a plasticity of 150 to 450 at 25 ° C. is there.

  The curable fixed silicone rubber composition further comprises a crosslinking agent, a curing catalyst, a filler, a thixotropic agent, a heat resistance improver, a cold resistance improver, a dehydrating agent, a rust preventive agent, E) an adhesion imparting component, You may contain a liquid reinforcing agent, a diluent, etc.

  This curable regular silicone rubber composition is cured by a condensation crosslinking reaction by moisture at room temperature, and becomes a rubber elastic body. Curing of the curable regular silicone rubber composition is almost completed in 3 to 7 days in an environment of 20 ° C. and 55% RH, for example.

  The self-adhesive silicone rubber composition can be molded by a generally known rubber molding method, for example, by extrusion using an extruder, or by a two-roll, calendar roll, etc. It can be formed into a molded body having a desired shape.

  The molding of the self-adhesive silicone rubber composition is carried out under the condition that the self-adhesive silicone rubber composition is not cured. For example, in the case of the silicone rubber composition, it is preferably molded in a low temperature environment, and specifically, it is preferably molded at 0 ° C. or less. In the case of the curable regular silicone rubber composition, it is preferably molded in a low-humidity environment so that the curing reaction does not proceed with moisture or moisture in the atmosphere. Specifically, it is 23 ° C. or less and 20% RH. It is preferable to mold in the following.

  Since the seal packing materials 1 to 3 are formed by molding the self-adhesive silicone rubber composition, they do not flow in an uncured state, but are relatively soft and conform to the fastening state of the brazed pipe joint. Can be compressed. Moreover, since the said seal packing materials 1-3 have self-adhesion property, they can be adhere | attached on each brazed pipe joint in the state compressed as mentioned above. Thus, since the seal packing materials 1 to 3 are in pressure contact with the surfaces of the brazed pipe joints, they exhibit high sealing performance between the brazed pipe joints, and the inside of the pipe from the vicinity of the brazed pipe joints. It is possible to prevent the fluid flowing through the fluid from leaking out. Therefore, the seal packing materials 1 to 3 are excellent in the sealing performance of the brazed pipe joint, and the pipes having the brazed pipe joint can be connected in a liquid-tight state.

  Thus, when the seal packing materials 1 to 3 are in pressure contact with the surfaces of the brazed pipe joints, even if the brazed pipe joints are fastened in a single-tightened state, Even if vibration is transmitted from the outside or stress is applied from the outside, high sealing performance between the brazed pipe joints can be maintained for a long period of time. Therefore, the seal packing materials 1 to 3 can be used even if the brazed pipe joint is fastened in a single-tight state, or even if vibration is transmitted to the brazed pipe joint from the outside or stress is applied from the outside. It is excellent in the sealing performance of the attached pipe joint, and the pipes having the brazed pipe joint can be connected in a liquid-tight state over a long period of time.

  Moreover, since the said seal packing materials 1-3 shape | mold the said self-adhesive silicone rubber composition, when the fluid which distribute | circulates the inside of a pipe | tube is water, warm water, hot water, or water vapor | steam, with respect to these The durability is particularly high, and high sealing performance between the brazed pipe joints can be exhibited over a long period of time.

  The seal packing material for a brazed pipe joint according to the present invention is not limited to the above-described embodiments, and various modifications can be made within a range in which the object of the present invention can be achieved. For example, although the seal packing materials 1 to 3 are all formed in a single layer structure, in this invention, the seal packing material for a brazed pipe joint may be formed as a laminate of two or more layers. In this case, it is only necessary that the outer layers serving as both surfaces of the seal packing material for brazed pipe joints be formed of the self-adhesive silicone rubber composition, and the intermediate layer is formed in addition to the self-adhesive silicone rubber composition. Further, it may be made of metal, resin or the like.

  Moreover, although the said seal packing materials 1-3 are formed in the ring shape or strip | belt shape, in this invention, the seal packing material for brazed pipe joints may be shape | molded in the other shape.

  The pipe connection method according to the present invention is a method of connecting pipes having brazed pipe joints with the brazed pipe joint, wherein the first pipe and second pipe having the brazed pipe joint are The flanged pipe joints are arranged so that the flanged pipe joints face each other, and a seal packing material for a flanged pipe joint formed by molding a self-adhesive silicone rubber composition between the flanged pipe joints. Is fastened with a fastener to compress the seal packing material for brazed pipe joints and harden the seal packing material for brazed pipe joints.

  In the pipe connection method according to the present invention (hereinafter sometimes referred to as the method according to the present invention), at least two seal packing materials for brazed pipe joints according to the present invention and pipes to be connected are prepared. The seal packing material for brazed joints is as described above, and specifically, the seal packing material 2 is prepared. The pipe to be prepared is a pipe having a brazed pipe joint at its end, as described above. In the method according to the present invention, as shown in FIG. 2, the water pipe disposed at a position where vibration from the outside is transmitted is formed at the pipe main body 12 and the end of the pipe main body 12, and the end face has The first pipe 11 provided with the brazed pipe joint 13 made of 14, and the pipe body 22 and the brazed pipe joint 23 made of the hook 24 formed at the end of the pipe main body 22 and made of the hook 24. A second tube 21 is prepared. Eight insertion holes 15 and 25 through which the bolts 32 of the fasteners 31 are inserted are formed in the flange 14 of the first tube 11 and the flange 24 of the second tube 21 at equal intervals in the circumferential direction. .

  In the method according to the present invention, the brazed pipe joint 13 of the first pipe 11 and the brazed pipe joint 23 of the second pipe 21 are then preferably arranged such that the axis of the first pipe 11 The 1st pipe | tube 11 and the 2nd pipe | tube 21 are arrange | positioned in series so that the axis line with the 2nd pipe | tube 21 may correspond.

  In the method according to the present invention, a primer is applied to the surface of the ridge 14 and / or the ridge 24 as desired. This primer is not particularly limited, and is appropriately selected according to, for example, the self-adhesive silicone rubber composition. Specifically, primers C, MT, D-2, U, T, FES-1 (trade names) , Both of which are manufactured by Shin-Etsu Chemical Co., Ltd.). In particular, when the self-adhesive silicone rubber composition is a condensation curable silicone rubber composition, it is preferable to apply a primer.

  Next, in the method according to the present invention, the seal packing material 2 is inserted between the flanged joints 13 and 14 that are disposed facing each other. At this time, the seal packing material 2 is disposed so that the through hole 2a thereof substantially coincides with the insertion holes 15 and 25 drilled in the flanges 14 and 24, respectively.

  In the method according to the present invention, the brazed pipe joints 13 and 23 are then fastened with the fasteners 31 to compress the seal packing material 2. For example, the bolt 32 is inserted into the insertion hole 15, the through hole 2 a and the insertion hole 25 in this order from the flanged pipe joint 13 side, and the tip of the bolt 32 protruding from the flange 24 is fastened with the nut 33. At this time, the brazed pipe joints 13 and 23 are fastened so that the seal packing material 2 is compressed. In this invention, since the seal packing material 2 is compressed and deformed following the fastening state of the brazed pipe joints 13 and 23, the brazed pipe joints 13 and 23 may be fastened in a single-tightened state. In order to secure a higher sealing performance, it is preferable to fasten the brazed pipe joints 13 and 23 with a uniform tightening force. In this invention, the fastening amount of the brazed pipe joints 13 and 23 is not particularly limited as long as the seal packing material 2 is compressed. For example, the thickness of the seal packing material 2 after compression is the seal before compression. It can adjust so that it may become 25 to 75% of the thickness of the packing material 2. FIG.

  In the method according to the present invention, the seal packing material 2 is then cured while maintaining this fastening state. When the seal packing material 2 is cured, a seal packing 5 for a brazed pipe joint is obtained. When the seal packing material 2 is formed of the addition-curable silicone rubber composition, the seal packing material 2 can be cured by applying heat to the seal packing material 2. Heating to the seal packing material 2 is performed so that the temperature is relatively higher than that of the seal packing material 2 before curing. For example, the seal packing material 2 stored at a low temperature can be cured by leaving it at room temperature. When the seal packing material 2 is formed of the condensation curable silicone rubber composition, the seal packing material 2 can be cured by applying moisture to the seal packing material 2. The supply of moisture to the seal packing material 2 can be cured by leaving it under a relatively higher humidity than the seal packing material 2 before curing. For example, the seal packing material 2 that is hermetically sealed can be cured by leaving it at room temperature.

  In the method according to the present invention, since the seal packing material 2 is interposed between the brazed pipe joints 13 and 23 and the brazed pipe joints 13 and 23 are fastened, the seal packing material 2 is fastened to the fastener 31. It can be made to adhere to each of the brazed pipe joints 13 and 23 in a compressed state so as to conform to the above. Thus, since the seal packing material 2 is in pressure contact with the surfaces of the brazed pipe joints 13 and 23, the brazed pipe joints 13 and 23 exhibit high sealing properties, and the brazed pipe joint 13 and The fluid can be prevented from leaking from the vicinity of each of the 23. Therefore, the method according to the present invention is excellent in sealing performance with the brazed pipe joints 13 and 23, and includes the first pipe 11 having the brazed pipe joint 13 and the second pipe 21 having the brazed pipe joint 23. It can be connected in a liquid-tight state.

  Thus, in the method according to the present invention, when the seal packing material 2 is brought into pressure contact with the respective surfaces of the brazed pipe joints 13 and 23, even if the brazed pipe joints 13 and 23 are fastened in a single-clamped state. Moreover, even if vibration is transmitted to the brazed pipe joints 13 and 23 from the outside or stress is applied from the outside, the high sealability between the brazed pipe joints 13 and 23 can be maintained for a long period of time. Therefore, in the method according to the present invention, even if the brazed pipe joints 13 and 23 are fastened in a single-clamped state, vibration is transmitted to the brazed pipe joints 13 and 23 from the outside or stress is applied from the outside. Even if it is excellent in the sealing performance with the brazed pipe joints 13 and 23, the 1st pipe | tube 11 and the 2nd pipe | tube 21 can be connected in a liquid-tight state over a long period of time.

  Further, in the method according to the present invention, the first pipe 11 and the second pipe 21 are connected using the seal packing material 2, and therefore the fluid flowing through the pipes 11 and 21 is water or hot water. In the case of hot water or steam, durability against these is particularly high, and high sealing performance between the brazed pipe joints 13 and 23 can be exhibited over a long period of time.

  The pipe connection method according to the present invention is not limited to the above-described embodiments, and various modifications can be made within a range in which the object of the present invention can be achieved. For example, in the above-described method according to the present invention, the seal packing material 2 having a through hole 2a is used, but in the present invention, the seal packing material 1 having no through hole is used. The through hole may be drilled when inserted between the brazed pipe joints, and the seal packing material 3 may be arranged in a ring shape on the surface of the brazed pipe joint.

Example 1
A first pipe body 12 having an inner diameter of 150 mm and a wall thickness of 4.5 mm and a brazed pipe joint 13 formed at the end of the pipe body 12 and having an outer diameter of 200 mm and a wall thickness of 4.5 mm. Tube 11 and a second tube 12 similar to the first tube 11 were prepared. The diameters of the insertion holes 15 and 25 in the first tube 11 and the second tube 12 were 10 mm.

  On the other hand, a seal packing material 2 shown in FIG. This seal packing material 2 is the condensation-curing silicone rubber composition (trade name “Polymer Ace HJ-14S”, manufactured by Shin-Etsu Polymer Co., Ltd.), formed into a ring-shaped flat shape having an outer diameter of 185 mm and an inner diameter of 150 mm. The diameter of the through hole 2a was 10 mm.

The condensation curable silicone rubber composition had a Williams plasticity (25 ° C.) of 200 and a tensile strength after curing of 10 kgf / cm ² .

  The first pipe 11 and the second pipe 21 are arranged in series so that the brazed pipe joint 13 to which the primer is applied and the brazed pipe joint 23 to which the primer is applied face each other. The seal packing material 2 was inserted so that the insertion holes 15 and 25 and the through hole 2a coincided with each other. Next, each of the eight bolts 32 is inserted into the insertion hole 15, the through hole 2 a and the insertion hole 25 in order from the flanged pipe joint 13 side, and the tip of the bolt 32 protruding from the flange 24 is uniformly tightened with the nut 33. We concluded to become power. The distance between the brazed pipe joint 13 and the brazed pipe joint 23 at this time, that is, the thickness of the seal packing material 2 after compression was set to about 50% of the thickness of the seal packing material 2 before compression. The seal packing material 2 was allowed to stand at room temperature as it was, and the first tube 11 and the second tube 12 were connected.

(Example 2)
Instead of the seal packing material 2, using the seal packing material 2 formed of the condensation curable silicone rubber composition (trade name “Polymer Ace HJ-1588L”, manufactured by Shin-Etsu Polymer Co., Ltd.), The first tube 11 and the second tube 12 were connected in the same manner as in Example 1 except that the primer was not applied to 23. The condensation curable silicone rubber composition had a Williams plasticity (25 ° C.) of 200 and a tensile strength after curing of 10 kgf / cm ² .

(Example 3)
Instead of the seal packing material 2, a brazed pipe joint 13 and a seal packing material 2 formed of an addition-curable silicone rubber composition (trade name “Polymer Ace HR-2388S”, manufactured by Shin-Etsu Polymer Co., Ltd.) The first tube 11 and the second tube 12 were connected in the same manner as in Example 1 except that the primer was not applied to 23. This condensation-curable silicone rubber composition had a Williams plasticity (25 ° C.) of 270 and a tensile strength after curing of 10 kgf / cm ² .

(Comparative Example 1)
The first tube 11 and the second tube 12 are basically the same as in Example 1 except that the curing reaction is not performed using a packing formed of EPDM instead of the seal packing material 2. And connected. The seal packing material 2 is a cured body.

  Since all of the seal packing materials 2 of Examples 1 to 3 have self-adhesive properties, these seal packing materials 2 are brazed pipes even when vibration is transmitted to the pipes 11 and 12 from the outside. While the joint 13 and the brazed pipe joint 23 can be bonded and connected to each other in a liquid-tight state with high sealing performance, the packing of Comparative Example 1 is made of EPDM and does not have self-adhesiveness. Is simply sandwiched between the pipes 11 and 12, and the sealing performance is not so high. In particular, when vibration is transmitted from the outside to the pipes 11 and 12, it is easy for the fluid flowing through the inside to easily leak. Guessed.

(Water leak test)
In order to verify the above estimation, a leak test was performed using a connection body of the first pipe 11 and the second pipe 12 connected in Examples 1 to 3 and Comparative Example 1. Specifically, after closing one opening of these connecting bodies and filling the inside with the other opening, the other opening is left standing for one day, and then the connection between the first pipe 11 and the second pipe 12 is made. Water leakage was confirmed from the part, that is, between the brazed pipe joints 13 and / or 14 and the seal packing material 2 or the packing. As a result, the connection bodies of Examples 1 to 3 could not confirm water leakage from the connection portion, whereas the connection body of Comparative Example 1 could confirm water leakage from the connection portion.

  The pipe in which the seal packing material for a flanged pipe joint according to the present invention is used, and the pipe connected by the pipe connecting method according to the present invention form various pipes for household use, factory use, construction use, etc. Or, pipes used for various pipes for home use, factory use, construction use, etc. are suitable, and form various pipes that are placed in locations, applications, and devices where external vibrations are transmitted or external stresses are applied. Particularly suitable are pipes that are used, or pipes that are used for various pipes provided in positions, applications, and devices where external vibrations are transmitted or stress is applied from the outside. Examples of the pipes arranged in the position, application, and apparatus include various pipes near pumps or reaction kettles, various pipes arranged in trains, bullet trains, automobiles, and the like. Examples include water pipes, drain pipes, fuel pipes, air ducts, waste discharge pipes, and the like. Focusing on fluids, these pipes include, for example, pipes through which liquids such as water, hot water, hot water, oil, liquid refrigerant, and liquid heat medium, or gases such as air, water vapor, and inert gas circulate. More specifically, for example, drainage pipes such as a washroom, a hand washroom, a cooking table, a water supply pipe, various oil pipes, and the like. In addition, conditions for fluid to flow through these pipes, for example, the kind of fluid, circulation pressure, circulation speed, temperature, etc. are not particularly limited.

1, 2, 3 (for brazed pipe joint) seal packing material 2 a through hole 5 brazed pipe joint seal packing 11 first pipe 12, 22 pipe main body 13, 23 brazed pipe joint 14, 25 insertion hole 21 first 2 pipe 31 fastener 32 bolt 33 nut

Claims (3)

  A seal packing material for brazed pipe joints formed by molding a self-adhesive silicone rubber composition.   The seal packing material for a brazed pipe joint according to claim 1, wherein the self-adhesive silicone rubber composition is molded into a ring shape or a band shape. A method of connecting a pipe having a brazed pipe joint,
The first pipe and the second pipe having a brazed pipe joint are arranged so that the brazed pipe joints face each other,
Between the brazed pipe joints, a seal packing material for brazed pipe joints formed by molding a self-adhesive silicone rubber composition, is inserted,
Fasten the brazed pipe joints with a fastener to compress the seal packing material for the brazed pipe joint,
A pipe connection method for curing the seal packing material for a brazed pipe joint.

Images