JPS62190280A - Semiliquid sealing material and method for water stopping at tail sealing part of shielded digging machine using said material - Google Patents

Abstract

PURPOSE:The titled sealing material which is suitable as packing for tail sealing part of shielded digging machine, has extremely improved water pressure- resistant performance and can miniaturize the tail sealing part, obtained by blending a hydrocarbon oil with a liquid resin, asbestos and synthetic fibers. CONSTITUTION:In a tail sealing part 13 of a shielded digging machine 1 having a constitution wherein a semiliquid sealing material is packed into between a pair of tail sealing rings 19 having an outer layer of a sealing plate layer 15 and an inner layer of a wire brush layer 17 equipped with a wire mesh 25, a sealing material 51 obtained by blending a hydrocarbon oil with a liquid resin, asbestos and synthetic fibers is packed into at least the wire brush layers 17 of each of the tail sealing rings 19 to give the tail sealing part of the shielded digging machine using the aimed sealing material. EFFECT:Packing operation time of sealing material can be shortened.

Description

[Detailed Description of the Invention] <Industrial Application Field> One of the present inventions relates to a semi-fluid sealing material.For example, in a shield tunneling machine, the outer layer is a sealing plate layer and the inner layer is a wire with a wire mesh. It is suitable for use by being filled between a pair of tail seal rings as a brush layer.

Another aspect of the present invention relates to a method of using the semi-fluid sealing material.

In addition, in the subscript, semi-fluid sealing material (hereinafter abbreviated as "sealing material") is defined by the consistency (JISK222
0.25°C) in the range of 160 to 210.

<Conventional technology> A schematic diagram of the shield tunneling machine is shown in Figure 0'S3.

The shield excavator 1 has a cylindrical shape with a bottom, and the bottom part is a cutter part 3 for excavating the ground. The open part (tail part 5) is fitted with a two-sand one-output tact 7. This 4Jl output tact 7 is composed of a large number of duct segments 7a, and as the seal I/excavation machine I advances, the six-day front part is assembled inside the shield excavation machine I. A plunger 9.9 is disposed to press the lot 11.11 against the front end of the dry mountain tact 7, and the reaction force from the discharge tact 7 is used as the propulsion force for the shield excavator 1.

As the drilled hole 11 is formed in this way, backfilling agent
4 will be expanded one after another, and the collapse of the excavated hole 11 will be prevented.

The reference numeral 13 in the figure is 1- The backing agent 14 and base wood are the seal I.
This is a tail seal part that prevents leakage into the excavator 1.

FIG. 4 is a cross-sectional view of the tail seal part 13 (rV-rV arrow line cross-sectional view in FIG. 3). As shown in the figure, the tail seal part 13 has a seal plate layer 15 on the outside and a wire brush layer 17 on the inside. A sealing material 21 is filled between a pair of tail seal rings 19.

This sealing material 21 is petroleum-based grease or wood +11r.
This is a composition in which M group 4423 is mixed in I. Soshite,
The seal material 21 is between the tail seal rings 19 and 19 (
Each wire brush layer 17, 17 is also filled with water, and because of its semi-fluid H, it also fills the stage X between each tact segment i and 7a of the dry mountain duct 7, and performs a sealing action. play. Of course, even when the shield tunneling machine l moves, the above-mentioned seal does not lose 1. The reason is that the fiber material 23 contained in the sealing material 21 gets entangled with each wire jJli 17a of the wire brush layer 17. It is thought that this is because it moves as a ground material.
9-147798).

By the way, as shown in FIG. 5, the sealing plate layer 15 functions to converge the wire brush layer 17 (preventing the wire fibers 17a from springing up).

(There is no direct contact with the outer peripheral surface of the A outlet duct 7, so
Specific sealing in the tail seal portion 13 is performed at a portion of the wire brush layer 17 that contacts the discharge tact 7.

Incidentally, recently, as shown in FIG. 5, a tail seal ring 19 having a wire mesh 25 in the wire brush layer 17 is being used.

<Problems to be Solved by the Invention> In order to investigate the performance of the sealing material, the inventors conducted a water pressure test under the following conditions.

First, reference numeral 35 in FIG. 0, which is used to create the water pressure test device 31 shown in FIG.
; 15■-) is left open. An inner sill 37 (inner diameter L2.27, height L3: 55 m1) is arranged on the soil surface of the substrate 35 so as to have the same axis as the through hole 33. This inner cylinder 37 further includes a hydraulic cylinder 3
Then, stainless steel gold 1139 (20 mesh, direct expansion 27 m) is inserted into the inner cylinder 37.
m) is laid down, and the sealing material 21 (thickness L4° 20+ua) is filled into the space 1-, and wood 41 is further filled until the inner sill 37 is full. Reference numeral 43 denotes oil, and pressure is arbitrarily applied by a hydraulic system (not shown). Note that the wire mesh 39 is laid on the tail seal portion 13 shown in FIG.

Calcium soap grease (J
Add the fiber material 23 to IS2 type No. 2) and seal the tail seal part 1.
After adjusting the consistency to actually be used in step 3, it was left to stand for 48 hours and then used.

Then, as a result of gradually increasing the oil pressure by 1, the water pressure decreased to 1.
Water 41 is discharged from the through hole 33 at a pressure lower than kgf/cm2.
(See Table 1, Conventional Example 1.II6) However, of course, there was no damage to the wire mesh 39 or leakage of the sealant 21.If the water pressure resistance of the sealant 21 is low, it is difficult to carry out excavation work deep underground. When this is done, the water pressure of groundwater is high, so it is necessary to increase the convergence of the tail seal portion 13 (wire brush layer 17 at 45) and thicken the layer of sealing material 21.

Furthermore, the sealing material 21 mixed with the fiber material 23 is highly tangled with itself, making it difficult to fill between the tail seal rings 19 using a grease pump. 1 before filling is completed.
Sometimes it takes ~2 days. That is, the conventional sealing material 21
(1) There are many parts used, and the cost is high, and the tail seal part 13
Make it larger.

(11) Poor filling workability.

(iii) For example, at a subway work site, 4 kgf
/c■2 (equivalent to groundwater pressure at 40m underground) or higher water pressure resistance is required. By the way, since the environmental conditions in the laboratory and the field are different, 4kgf/c+e in the laboratory
Even if a water pressure resistance of 2 is obtained, it cannot be used as is at the work site of 1. Therefore, normally, as an experimental value, a water pressure resistance of 2 times that of the field can be obtained. It is said to be good.

However, there is a problem in that conventional sealing materials having a water pressure resistance of less than 1 kgf/cm2 may not provide sufficient sealing performance in the tail seal portion of the excavator.

Dingdan and action for solving problems〉The uninvented name is
As a result of intensive research to solve these problems, we have completed the following invention.

The first invention is a sealing material (hereinafter referred to as "reinforced sealing material") made by mixing hydrogenated oil with liquid resin, asbestos, and synthetic MhIa, and has higher water pressure resistance than conventional products. .

Each component of the reinforcing sealing material according to the first invention will be described in detail below.

(i) JQ: Mineral oil-based medium oil (10 machine oil or more = -) is used as the hydrogenated oil, and the amount is 20 to 50% of the total weight.

If it is less than 20 weights and 1%, the consistency of the reinforcing sealing material will be high, while if it exceeds 50 weights and 1X%, the consistency will be undesirably low.

(ii) The liquid resin is mixed to impart viscosity to the reinforcing sealing material, and if it exceeds 30% by weight of the total, the reinforcing sealing material becomes too sticky and becomes difficult to fill, which is not preferred.

If this liquid resin is not mixed, the desired water pressure resistance cannot be obtained in the sealing material, which is undesirable (see Comparative Example 2 in Table 1).

The liquid resin must be a resin that is liquid at room temperature, such as polybutene.Since hydrogen oil is mixed with the sealing material, solid low-molecular-weight hydrocarbon resin (petroleum resin, etc.) cannot be used. However, the liquid does not have the desired water resistance and is too adhesive to be used as a sealing material for the tail seal portion.

(iii) Asbestos can be mixed in up to 60% by weight of the total, but if it exceeds 60% by weight and 9% by weight, the sealing material becomes brick-like, which is not preferable.

If this asbestos is not mixed, the desired water pressure resistance will not be achieved in the sealing material, which is undesirable (Comparative Example II in Table 1).
reference).

Note that asbestos expands when it absorbs groundwater, further increasing the water pressure resistance of the reinforced sealing material in the tail seal portion. In addition, asbestos, along with the synthetic u&fibre described below, becomes entangled with the wire fibers and wire mesh of the tail seal ring and acts as a base material.

Furthermore, by incorporating asbestos, the reinforced sealing material has a higher specific gravity than water, which solves the problem of the sealing material floating when underground water intrudes, which often occurs with conventional grease-based sealing materials.

In addition, the asbestos makes the discharge duct abutting surface of the tail seal part "rough", which improves water performance.

Furthermore, since asbestos is of *A quality, the wood-reinforced sealing material has excellent fire resistance and antibacterial properties.

(lma) As the synthetic fiber, one type or multiple types of water-resistant m1II such as Tetron, vinylon, polyester, etc. can be used. The mixing ratio of this synthetic fiber to the whole is not limited to 4.-, and may be, for example, 0.1 gl, iS (%).However, if it is mixed in excess of 20 weight and 41%, the material cost will be -1.
- This is not preferable.

Of course, if this synthetic fiber is not mixed, the desired water pressure resistance cannot be obtained in the sealing material, which is not preferable (see Comparative Example 2 in Table 1).

Further, the length and thickness of the synthetic fibers are not particularly limited, and for example, synthetic fibers having a length of 2 to 10 deniers and a thickness of 0.5 to 10 deniers may be used.

It is thought that in this reinforcing sealing material, this synthetic fiber is entangled with asbestos and forms an angle of ".11°" of the asbestos.

(Ma)'' - The reporter component is mixed with a conventional mixer to adjust the consistency to about 160-210.

In addition to the ingredients explained above, calcium carbonate and various coloring agents are used to adjust consistency.

Of course, it is possible to mix in antioxidants, etc. However, adding calcium soap (i.e., turning hydrocarbon oil into grease) solidifies the sealing material, which is undesirable. It is thought that the presence of this substance causes a polymerization reaction of hydrocarbon oil.

The second invention is 1. Fill the wire brush layer (equipped with wire mesh) of the tail seal ring with the reinforcing sealant,
11- Method of swimming the tail seal portion using a reinforcing sealing material in which the r7 gap formed between each wire brush layer is filled with a sealing material having a higher rrf plasticity of 1 than the reinforcing sealing material 1-.

<Effects of the Invention> Effect 1 of the first invention, the reinforcing sealing material according to the first invention having the composition described above, when combined with a wire mesh, has a thickness of at least 20a+m and a capacity of 18 kgf/cs2 or more, as shown in Table 1. It has water pressure resistance of
This number is required at the subway exit site (fi
(8 kgf/c■2 in experiment 4ti) and is said to have an extremely high sealing effect.
It exceeds kgf/cm2 (3 times image 1).

Therefore, when filling the tail seal portion of a shield tunneling machine, even if the width of the sealing material layer is made small, that is, even if a small amount of sealing material is used, reliable sealing performance against groundwater etc. can be obtained. Therefore, not only can the tail seal portion be made smaller, but also the time required to fill the sealing material can be reduced.

Embodiments and effects of the second invention> Next, the second invention will be described with reference to FIG. 1. Incidentally, the same members as in the conventional example (FIG. 5) are given the same reference numerals and their explanations will be omitted.

The present invention is a tree anchoring method in which the reinforcing seal material according to the first invention is used for the existing tail seal portion 13 of the shield tunneling machine 1.

As described above, the reinforced sealing material according to the first invention has extremely excellent water pressure resistance. Therefore, this reinforcing sealing material 51
is filled only into each wire brush layer 17 and 17 provided with the wire mesh 25 of the tail seal portion 13. As a result, if each wire brush layer 17.17 has a thickness of at least 20mm, sufficient sealing performance against groundwater etc. can be achieved1).Furthermore, the reinforcing sealing material 51 is filled manually.

On the other hand, the gaps 53 formed between each wire brush layer 17 and 17 are filled with a sealing material 55 having higher plasticity than the reinforcing sealing material 51 (for example, JIS 2 layer No. 2 cup grease), and each tail This sealing material 55, which prevents the seal ring 19 from falling inward, has high plasticity, so it has good pumping performance and can significantly reduce filling time. An example of the material is a biped cup grease mixed with 10 to 40 weight percent of YRN calcium.

In addition, in the tail seal portion 13, the seal plate layer 15
may also be provided inside the wire brush layer 17, and the wire brush layer 17 may be sandwiched between two sealing plate layers.

Furthermore, when the wire mesh 25 was removed from the wire brush layer 17 in the tail seal portion 13, it was difficult to obtain a desired sealing performance.

<Example> Next, the reinforcing sealing material according to the first invention will be described in more detail with reference to Examples and Comparative Examples.

46 machine oil (11 Oil Co., Ltd.) as a hydrocarbon oil
JJ; fO product name r 46 machine oil") and 500 machine oil (manufactured by 11 Oil Co., Ltd.; product name "Super CJ"), polybutene (manufactured by 11 Oil Co., Ltd.; product name "Super CJ") was used as a liquid resin. r2oON''), asbeth) (Canada IL), Tetron Sengumi (manufactured by Meijin Co., Ltd.; thickness 2 denier, length 5 ffim) and necessary calcium carbonate (manufactured by 11 Tofunka (a); mi Product name: “Ultra Fine Grain N5”
100J) was mixed in a normal mixer at room temperature to prepare the reinforcing sealing material of Examples (Work ~ The materials were prepared with the same properties, but Comparative Example 1 did not contain liquid resin, Comparative Example II did not contain asbestos, and Comparative Example (2) did not contain synthetic fibers.

1. After preparing the sealing materials of the Examples and Comparative Examples, the sealing materials were left for 48 hours, filled into the water pressure test device 31 shown in FIG. : The pressure when the water 41 spouts out from the through hole 33 was set to All+.

Of course, no breakage of the wire mesh 39 or leakage of the sealant occurred.

Also, lT)! For water-based products, apply each sealant to the inner wall of the beaker.
After 51 iu L of water was poured into the beaker and stirred for 30 minutes, it was visually determined whether the sealant was dispersed in the water. Consistency is JISK2220 (25℃)
by.

From the results in Table 1, it can be seen that the reinforced sealing material according to the first invention has excellent water pressure resistance.

Table 1 *The numbers for each component indicate the percentage of type seedlings.

*Water resistance is when each sealing material is applied to the inner wall of a beaker, wood is placed in the beaker, and after stirring for 30 minutes, the sealing material is not dispersed in the water and is dispersed by °゛O°''1. was marked as “×”.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the tail seal portion 13 filled with a semi-fluid sealing material according to the second invention, Fig. 2 is a sectional view of a water pressure tester manufactured by the inventor, and Fig. 3 is a sectional view of a shield tunneling machine l. FIG. 4 is a cross-sectional view schematically showing the rV-IV in FIG.
FIG. 5 is a sectional view taken along the arrow line and shows a state in which the semi-fluid sealing material 21 is filled in the conventional tail seal portion 13. l...Shield excavator, 13...Tail seal part. 15... Seal plate layer. 17... Wire brush layer, 19... Tail seal ring, 25... Wire mesh. 51... Reinforced (semi-fluid) sealing material. Special Application: Chukyo Kasei Kogyo Co., Ltd. Representative, Patent Attorney [11 Solid Section;
1.1 Spontaneous amendment procedure amendment entry 1, Indication of the case 1988 Patent application No. 031740 2, Title of the invention Semi-fluid sealing material and tail seal part of a shield excavator using this semi-fluid sealing material 3. Relationship with the case of the person making the amendment Patent application Name of address Chukyo Kasei Kogyo Co., Ltd. 4 Address of agent 2-11-1 Sakae, Naka-ku, Nagoya, Aichi Prefecture 480
Details of amendments to Specification No. 8 and Drawing 6 (1) Unwritten amendments will be made to the specification as shown in the attached sheet. (2) Figure 3 of the drawings shall be amended as shown in the attached sheet. 7. List of attached documents (corrected full text) Description 1. Title of the invention Semi-fluid sealing material and tail seal portion of a shield excavator using this semi-fluid sealing material 2. Claim 1. Hydrocarbons A semi-fluid sealing material characterized by liquid resin, asbestos, and synthetic fibers mixed in oil. 2. In the tail seal portion of a shield excavator, the structure is such that a semi-fluid sealing material is filled between a pair of tail seal rings whose outer layer is a seal plate layer and whose inner layer is a wire brush layer with a wire mesh, 3. Detailed Description of the Invention (Field of Industrial Application) One of the present inventions relates to a semi-fluid sealing material, for example, in a shield tunneling machine, the outer layer is a sealing plate layer and the inner layer is a wire with a wire mesh. It is suitable for use by being filled between a pair of tail seal rings as a brush layer. Another aspect of the present invention relates to the tail seal part of an excavator using the above-mentioned semi-fluid sealing material. Consistency (JI 5K2220.25℃) 1
60 to 280. <Prior Art> A schematic diagram of the above-mentioned shield tunneling machine is shown in FIG. 3. The shield excavator 1 has a cylindrical shape with a bottom, and the bottom part is a cutter part 3 for excavating the ground. The opening (tail portion 5) is fitted into the earth and sand discharge duct 7. This discharge duct 7 is composed of a large number of duct segments 7a, and as the shield excavator 1 advances, the foremost part is assembled within the shield excavator 1. A plurality of shield jacks 9 are disposed inside the shield excavator 1, and a rod 11 disposed at the tip thereof is pressed against the front end of the discharge duct 7 to prevent reaction from the discharge duct 7. Power shield excavator 1
It is the driving force behind this. As the excavated hole 12 is formed in this manner, the backfilling agent 14 is sequentially injected into the gap between the discharge duct 7 and the circumferential surface of the excavated hole 12, thereby preventing the excavated hole 12 from collapsing. Reference numeral 13 in the figure is a tail seal portion that prevents the backfilling agent 14 and groundwater from leaking into the shield excavator 1. FIG. 4 is a cross-sectional view of the tail seal portion 13 (cross-sectional view taken along the line IV-IV in FIG. 3). As shown in the figure, the tail seal portion 13 has a structure in which a sealing material 21 is filled between a pair of tail seal rings 19 having a seal plate layer 15 on the outside and a wire brush layer 17 on the inside. This sealing material 21 has a composition in which a fibrous material 23 is mixed into petroleum grease or resin. This sealing material 21 is held between the tail seal rings 19.19 (which are also filled in each wire brush layer 17.17), and due to its semi-fluidity, it is held between each duct segment 78 of the discharge duct 7. It performs a sealing action by filling even the difference in level. Of course, the above-mentioned sealing property is not lost even when the shield tunneling machine 1 moves. The reason is thought to be that the fiber material 23 contained in the sealing material 21 is entangled with each wire fiber 17a of the wire brush layer 17 and acts as a joint material (see Japanese Utility Model Application No. 59-147798).
. By the way, as shown in FIG. 5, the sealing plate layer 15 functions to converge the wire brush layer 17 (preventing the wire fibers 17a from flying up) and does not directly contact the outer peripheral surface of the discharge duct 7. Therefore, the specific sealing action in the tail seal portion 13 is performed at the portion of the wire brush layer 17 that comes into contact with the discharge duct 7. Incidentally, recently, as shown in FIG. 5, a tail seal ring 19 having a wire mesh 25 in the wire brush layer 17 is being used. <Problems to be Solved by the Invention> The present inventor conducted a water pressure test under the following conditions in order to examine the performance of the sealing material. First, a water pressure test device 31 shown in FIG. 2 was created. The reference numeral 35 in the figure is a substrate, and the through hole 33 (diameter Ll; 15
mm) is open. On the upper surface of the substrate 35, an inner cylinder 37 (inner diameter L2;
27 mm, height L3: 55 mm). This inner cylinder 37 is further inserted into a hydraulic cylinder 39, and a stainless steel wire mesh 39 (20 mesh, 27 mm stone carved disk shape) is laid inside the inner cylinder 37, and a sealing material is placed on top of it. 21 (thickness L4; 20
II1m) and further fill with water 41 until the inner cylinder 37 is full. Reference numeral 43 denotes oil, and pressure is arbitrarily applied by a hydraulic system (not shown). In addition, wire mesh 39
This is intended for the tail seal portion 13 shown in FIG. 5. Calcium soap grease (J
Add the fiber material 23 to IS2 type No. 2) and seal the tail seal part 1.
After adjusting the consistency to actually be used in step 3, it was left to stand for 48 hours and then used. Then, as a result of gradually increasing the oil pressure, the water pressure reached 1 k
Water 41 spouted out from the through hole 33 at a pressure lower than gf/cm2 (see Conventional Examples I and H in Table 1). Of course, gold it'
In this way, there is no damage to 139 and no leakage of sealing material 21.
If the water resistance pressure of the sealing material 21 is low, the water pressure of groundwater will be high when excavation work is performed deep underground, so the width of the tail seal portion 13 (especially the wire brush layer 17) is increased to make the sealing material 210 layer thick. There is a need. Furthermore, the sealing material 21 mixed with the fiber material 23 is highly tangled with itself, making it difficult to fill between the tail seal rings 19 using a grease pump. 1 before filling is completed.
Sometimes it takes ~2 days. That is, the conventional sealing material 21
(i) The amount used is large, the cost is high, and the tail seal part 13
Make it larger. (ii) Poor filling workability. (iii) For example, at a subway work site, 4 kgf
/cm2 (equivalent to groundwater pressure at 40 meters underground) or higher is required. By the way, since the environmental conditions are different between the laboratory and the field, even if water pressure resistance of 4 kgf/cm2 is obtained in the laboratory, it cannot be used as is at the above-mentioned subway work site. Therefore, it is generally considered that it is sufficient to obtain a water pressure resistance performance that is at least twice that of the field as an experimental value. However, there is a problem in that with conventional sealing materials whose water pressure resistance is less than 1 kgf/cm2, sufficient sealing performance may not be obtained in the tail seal portion of the excavator. Means and operation for solving the problems> The present inventors
As a result of intensive research to solve these problems,
Completed the following inventions. The first invention is a sealing material (hereinafter referred to as "reinforced sealing material") made by mixing liquid resin, asbestos, and synthetic fibers in hydrocarbon oil, and has higher water pressure resistance than conventional sealing materials. Each component of the reinforced sealing material according to the first invention will be described in detail below. (i) As the hydrocarbon oil, use mineral oil-based medium oil (10% machine oil or more) and make it 20 to 50% by weight of the whole. If it is less than 20% by weight, the consistency of the reinforced sealing material will be high,
On the other hand, if it exceeds 50% by weight, the consistency becomes low, which is not preferable. (if) The liquid resin is mixed in to impart viscosity to the reinforcing sealant, and if it exceeds 30% by weight of the total, the reinforcing sealant becomes too sticky and difficult to fill, which is not preferred. If this liquid resin is not mixed, the desired water pressure resistance cannot be obtained in the sealing material, which is undesirable (see Comparative Example I in Table 1). Note that the liquid resin must be a resin that is liquid at room temperature, such as bolybdenum. This reinforced sealing material is mixed with hydrocarbon oil, so solid low molecular weight hydrocarbon resin (petroleum resin, etc.)
Even if you add it, it will dissolve and become liquid, but the liquid will be
The desired water resistance cannot be obtained, and the adhesiveness is too strong to be used as a sealing material for the tail seal portion. (ii) Asbestos can be mixed in up to 60% by weight of the total, but if more than 60% by weight is mixed in, the sealing material becomes brick-like, which is not preferable. If this asbestos is not mixed, the desired water pressure resistance cannot be obtained in the sealing material, which is not preferable (see Comparative Example II in Table 1). Note that asbestos swells when it absorbs groundwater, further increasing the water pressure resistance of the reinforced sealing material in the tail seal portion 13. In addition, asbestos is also used in the wire fiber 17 of the tail seal ring 19, as well as the synthetic fibers listed below.
It also works as a joint material by intertwining with A25. Furthermore, by incorporating asbestos, the reinforced sealing material has a higher specific gravity than water, which solves the problem of the sealing material floating when underground water infiltrates, which often occurs with conventional grease-based sealing materials. In addition, asbestos makes the discharge duct abutting surface at the tail seal part "rough", improving water-stopping performance.Furthermore, since asbestos is inorganic, this reinforced sealing material has excellent fire resistance and antibacterial properties. (jv) Synthetic fibers include polyester and polyamide.One type or multiple types of strong water-resistant fibers such as polyethylene can be used.The mixing ratio of this synthetic fiber to the total is not particularly limited, and for example, It may be 0.1% by weight.
If more than 20% by weight is mixed in, the material cost will increase, which is not preferable. Of course, if this synthetic fiber is not mixed, the desired water pressure resistance cannot be obtained in the sealing material, which is not preferable (Comparative Example II in Table 1).
+Reference). Further, the length and thickness of synthetic fibers are not particularly limited, and for example, synthetic fibers having a length of 2 to 10 mm and a thickness of 0.5 to 10 deniers may be used. It is thought that in this reinforced sealing material, this synthetic fiber becomes entangled with asbestos and becomes the backbone of the asbestos. Note that vegetable fibers such as cellulose and pulp lack the tensile strength that can form the bones of asbestos. (V) The above components are mixed using a common mixer to adjust the consistency to about 160 to 280. In addition to the ingredients explained above, calcium carbonate and various coloring agents are used to adjust consistency. It goes without saying that an antioxidant or the like may be mixed in, but adding calcium soap (that is, turning hydrocarbon oil into grease) is not preferable because it solidifies the sealing material. It is thought that a crosslinking reaction between soap and asbestos occurs. A second invention is a tail seal portion of an excavator in which at least the wire brush layer 17 (equipped with a wire mesh) of the tail seal ring 19 is filled with the above-mentioned reinforced sealing material. Thereby, even if the sealing material to be filled into the spaces formed between the wire brush layers 17 has a higher fluidity, a predetermined sealing performance can be obtained in the tail seal portion 13. <Effects of the Invention> Effects of the First Invention The reinforced sealing material according to the first invention having the above composition has a resistance of 18 kgf/cm2 or more at a thickness of at least 20 mm when combined with a wire mesh, as shown in Table 1. Has hydraulic performance. This value not only fully satisfies the value required at subway construction sites (experimental value: 8 kgf/am2), but also exceeds 12 kgf/cm2 (experimental value), which is said to have an extremely high sealing effect.
3 times the value). Therefore, when filling the tail seal portion of a shield tunneling machine, even if the width of the sealing material layer is made small, that is, even if a small amount of sealing material is used, reliable sealing performance against groundwater and the like can be obtained. Therefore, not only can the tail seal portion be made smaller, but also the time required to fill the sealing material can be reduced. Embodiments and effects of the second invention> Next, the second invention will be described with reference to FIG. 1. Incidentally, the same members as in the conventional example (FIG. 5) are given the same reference numerals and their explanations will be omitted. The present invention relates to the tail seal portion 13 of the shield tunneling machine 1 using the reinforced sealing material according to the first invention. As described above, the reinforced sealing material according to the first invention has extremely excellent water pressure resistance. Therefore, this reinforcing sealing material 51
is filled only into each wire brush layer 17 and 17 provided with the wire mesh 25 of the tail seal portion 13. As a result, if the thickness of each wire brush layer 17.17 is at least 20 mm, sufficient sealing performance against groundwater and the like can be obtained. On the other hand, the voids [53 formed between each wire brush layer 17 and 17 are filled with a sealing material 55 (for example, JIS type 2 No. 2 cup grease) having higher fluidity than the reinforced sealing material 51, and each tail seal Prevents the ring 19.19 from falling inward. Since this sealing material 55 has high fluidity, it has good pumping performance and can significantly reduce filling time.Also, as a sealing material with higher fluidity than reinforced sealing material, calcium carbonate is added to the cup grease by 10 to 10%.
An example of this is a mixture of 40% and 2%. In addition, in the tail seal portion 13, the seal plate layer 15
may also be provided inside the wire brush layer 17, and the wire brush layer 17 may be sandwiched between two sealing plate layers. It goes without saying that the void 53 can be filled with the reinforced sealing material according to the first invention. Further, in the tail seal portion 13, gold 1! is applied from the wire brush layer 17! ! When 125 was removed, it was difficult to obtain the desired sealing performance. <Example> Next, the reinforced sealing material according to the first invention will be described in more detail with reference to Examples and Comparative Examples. Hydrocarbon oils include 46 machine oil (manufactured by Nippon Oil Co., Ltd.; trade name: "46 machine oil") and 500 machine oil (manufactured by Nippon Oil Co., Ltd.; product name: "46 machine oil").
Manufactured by a): Bolybdenum (manufactured by Nippon Oil Co., Ltd.; product name r2) is added as a liquid resin to the mixed oil of the product name "Super CJ".
0ONJ), asbestos (from Canada), Tetron fiber (
(manufactured by Ondai Co., Ltd.; thickness: 2 denier, length: 5 mm) and, if necessary, calcium carbonate (manufactured by Nitto Funka Co., Ltd.; trade name: "Ultrafine Particles N5100J") using a normal mixer at room temperature. The reinforcing sealing material of Example (I-IV) was prepared, and 48
The comparative examples, which were tested after standing for a period of time (see Table 1), were prepared using the same materials and under the same conditions as the examples.
does not contain synthetic fibers. After the sealing materials of the above Examples and Comparative Examples were prepared, they were left for 48 hours and then transferred to the water pressure tester 31 in FIG. 2 in the same manner as the conventional example (
Thickness: 20 mm), the oil pressure was gradually increased, and the pressure when water 41 spouted out from the through hole 33 was measured. Of course,
No breakage of gold 1i939 or leakage of sealant occurred. In addition, water resistance is achieved by applying each sealant to the inner wall of the beaker.
After pouring water into the beaker and stirring for 30 minutes, it was visually determined whether the sealant was dispersed in the water. Consistency is based on J I 5K2220 (25°C). From the results in Table 1, it can be seen that the reinforced sealing material according to the first invention has excellent water pressure resistance. Table 1 *Numbers for each component indicate weight%. *Water resistance is based on the case where each sealing material is applied to the inner wall of a beaker, water is poured into the beaker, and after stirring for 30 minutes, the sealing material is not dispersed in the water, but "O" is dispersed in the water. ×
゛°. 4. Brief description of the drawings Fig. 1 is a cross-sectional view of the tail seal portion 13 filled with a semi-fluid sealing material according to the second invention, Fig. 2 is a cross-sectional view of a water pressure tester manufactured by the inventor, 3 is a cross-sectional view schematically showing the shield tunneling machine 1, and FIG. 4 is a rV-IV in FIG. 3.
FIG. 5 is a sectional view taken along the arrow line and shows a state in which the semi-fluid sealing material 21 is filled in the conventional tail seal portion 13. DESCRIPTION OF SYMBOLS 1... Shield tunneling machine, 13... Tail seal part, 15... Seal plate layer, 17... Wire brush layer, 19... Tail seal ring, 25... Wire mesh, 51... Reinforced (semi-fluid) sealant. Patent application Jinchukyo Kasei Kogyo Co., Ltd.

Claims (1)

[Claims] 1. A semi-fluid sealing material characterized in that a liquid resin, asbestos and synthetic fibers are mixed in hydrocarbon oil. 2. In the tail seal portion of a shield excavator, the structure is such that a semi-fluid sealing material is filled between a pair of tail seal rings whose outer layer is a seal plate layer and whose inner layer is a wire brush layer with a wire mesh, The wire brush layer of each tail seal ring is filled with a semi-fluid sealing material (hereinafter referred to as "reinforced semi-fluid sealing material") having a composition in which liquid resin, asbestos and synthetic fibers are mixed in hydrocarbon oil. , a shield excavator using a semi-fluid sealing material, characterized in that the gaps formed between the wire brush layers are filled with a semi-fluid sealing material having higher plasticity than the reinforcing semi-fluid sealing material. How to stop water from the tail seal.