JPH0413144Y2 - - Google Patents

Description

[Detailed explanation of the idea]

Industrial Application Field This invention is used to line pipelines mainly buried underground, such as gas pipelines, water pipes, power lines, communication lines, etc., for the purpose of repairing or reinforcing the pipelines. It relates to a lining material used for lining the pipe, and in particular, it relates to a lining material used in a method in which the lining material is inserted into a pipe while being turned inside out using fluid pressure, and is adhered to the inner surface of the pipe using an adhesive to line the pipe. It is something. BACKGROUND TECHNOLOGY In recent years, for the purpose of repairing aging pipes or reinforcing them against earthquakes and vibrations, it has become common practice to line the various pipes as described above by pasting lining materials on their inner surfaces. It is being done. As described above, the method of lining the lining is to insert a flexible lining material coated with adhesive onto the inner surface into the pipe while turning it over using fluid pressure such as compressed air, and use the fluid pressure to insert the lining material into the pipe. In recent years, a method of lining the material by pressing it onto the inner surface and adhering it with the adhesive described above has been attracting particular attention in recent years. This method does not require digging along the entire length of the pipe during lining work; it is sufficient to drill holes only at both ends of the pipe to be lined, and the work can be carried out even if the pipe is slightly bent. And,
This method is attracting particular attention as an extremely superior construction method that can be used to construct long pipe sections in a short period of time. The lining material used in this method is:
The lining material must be able to withstand the pressure of the fluid during inversion, and even if the pipe line is broken due to external force, it must not break or lose its function. It is suitable that a synthetic resin coating layer is formed on the outer surface of a cylindrical woven fabric made by woven into cylindrical strips. In addition, especially in the case of small-diameter pipes with a nominal diameter of less than 100 mm, the driving force of the lining material when turning it over is small, and small-diameter pipes generally have many bends, making it difficult for the lining material to turn over. . As a lining material for such small-diameter pipes, a material with large elongation in the longitudinal direction is suitable, and the warp of the tubular woven fabric,
It is preferable to use a yarn in which a synthetic fiber yarn such as polyethylene terephthalate is wound around a polyurethane elastic yarn, or a yarn made of polybutylene terephthalate fiber. Problems that the invention aims to solve However, when lining small-diameter pipes with such lining materials, the coating layer of the lining material often peels off partially or the coating layer is damaged. It was. When we investigated the cause of this problem, we found that straight pipes and bent pipes are connected by threaded joints at bends in pipes, but the cut surfaces of the pipe ends at these joints are usually not deburred. many. In the lining material, it is the cylindrical woven fabric layer that comes into contact with this burr, and the burr does not directly damage the cylindrical woven fabric, but the burr may cause the lining material to locally protrude inward. The lining material that has not yet been turned over is rubbed by the protrusion, and the coating layers rub against each other locally, causing the coating layer to peel off from the tubular woven fabric or be damaged. Furthermore, if the weft of the tubular woven fabric gets caught in a burr and the grain shifts, the coating layer in that area becomes thinner and pinholes are more likely to occur. The present invention was devised in view of the above circumstances, and it is an object of the present invention to provide an excellent lining material in which the coating layer does not peel off over a wide range from the cylindrical woven fabric or break locally. That is. A more detailed investigation of the peeling phenomenon of the coating layer due to burrs shows that when peeling occurs between the coating layer and the warp of the tubular woven fabric, the peeling spreads in the length direction of the lining material, causing lifting. The ivy coating layer is often forced to one side by friction and breaks. On the other hand, the peeling that occurs between the covering layer and the weft threads of the tubular woven fabric tends to spread in the circumferential direction of the lining material, but not in the longitudinal direction.
It was found that the coating layer was less likely to break. Means for Solving the Problems The present invention provides a lining material used in a lining method in which the lining material is inserted into the pipe while being turned inside out using fluid pressure and bonded to the inner surface of the pipe via an adhesive. It is characterized in that a flexible synthetic resin coating layer is formed on the outer surface of a tubular woven fabric constructed of a twill weave structure in which the weft threads are largely exposed on the outer surface. Example An example of our school's proposal will be described below with reference to the drawings. The drawing shows a lining material 1 according to an embodiment of the present invention, in which a covering layer 3 is formed on the outer surface of a cylindrical woven fabric 2.
In this case, warp yarns 4 and weft yarns 5 are woven into a cylindrical shape with a twill weave structure in which the weft yarns 5 are largely exposed on the outside. Describing the composition of the above lining material in more detail,
The warp yarn 4 of the tubular woven fabric 2 is made of 280 yarns made by wrapping a crimped yarn of 150 denier polyethylene terephthalate fiber twice on both the left and right sides around a 210 denier polyurethane elastic yarn. For No. 5, a yarn made by twisting two crimped yarns of 150 denier polyethylene terephthalate fibers was used, and the yarn was driven at 20 strokes/inch, and the outer surface was 1/2.
It is woven into a cylindrical shape using the three-ply twill structure shown in step 2. The polyurethane elastic yarn alone exhibits an elongation rate of about 700%, which is too high to be used in the cylindrical woven fabric of the lining material, and its strength is 1 to 2 g/2.
d, so a crimped yarn of high-strength polyethylene terephthalate fiber is wrapped around the polyurethane elastic yarn to strengthen it and reduce the elongation to 120.
It is best to keep it to about %. In addition, in the above embodiment, expensive polyurethane elastic yarn is used as the warp of the tubular woven fabric, making the lining material expensive and making it difficult to manufacture thick polyurethane elastic yarn. As a lining material for a large-diameter pipe, it is preferable to use yarn made of polybutylene terephthalate fiber for the warp of a tubular woven fabric. For example, to explain the specific structure of a lining material for a pipe with a nominal diameter of 100 mm as an example, the warp is a yarn made of 10 crimped yarns of 150 d polybutylene terephthalate fiber twisted together. A total of 598 threads were used, with two threads aligned, and the weft was 14 threads consisting of three 500D crimped polyethylene terephthalate fibers twisted together.
It is woven at a rate of 1/2 twill and cylindrical strips so that the outer surface has a 1/2 triple twill weave structure. Next, as a comparative example, an example in which a tubular woven fabric is woven with a plain weave structure will be shown. The same yarns as those used in the above example were used for the warp and weft of the tubular woven fabric, and the amounts used were varied to produce a plain weave structure. For each of the cylindrical woven fabrics of the Examples and Comparative Examples, a polyester elastomer coating layer was formed on the outer surface of each of the cylindrical woven fabrics by extrusion molding under almost the same molding conditions. Here, each of the lining materials of the Examples and Comparative Examples was examined for its elasticity, adhesive strength between the cylindrical woven fabric and the covering layer, and damage resistance. Elasticity is measured by applying internal pressure to the lining material and measuring its outer diameter change and lengthwise elongation.The diameter is the outer diameter at each pressure in mm, and the elongation is the lengthwise elongation rate as %. It was shown in The adhesive strength is
Cut the lining material into 20mm wide strips and cut them into 180mm strips.
The peel strength was measured. The values in the table are average values (Kg/10mm width) converted to 10mm width. In addition, for trauma, a string-like object is inserted into the lining material, and while applying a predetermined fluid pressure to the lining material, the string-like object is pulled with a predetermined load and the lining material is turned over.
The lining material was inserted into a conduit in which 10 bent portions were formed by connecting straight pipes with a burr of approximately 3 mm on the cut surface with 90-degree elbows, and the presence or absence of damage to the coating layer after insertion was examined. The results of this test are shown in the table.

【table】

[Table] Effect As can be understood from the results shown in the table, in the comparative examples, changes in the number of warp threads have almost no effect on the adhesive strength, and as the number of weft threads decreases, the adhesive strength decreases. It can be seen that there is a decrease in This is because as the number of weft yarns decreases, the warp yarns float longer, so peeling easily spreads in the length direction along the warp yarns, and peeling progresses with a small force. In addition, in the lining material of the comparative example, it is possible to improve the adhesive force between the tubular woven fabric and the coating layer to some extent by adjusting the molding conditions of the coating layer, etc. This is undesirable because the elongation of the fabric in the warp direction may be lost, resulting in a very stiff texture. On the other hand, in the lining material of the present invention, many of the weft threads are exposed on the outer surface of the tubular woven fabric, and less of the warp threads are exposed, so peeling does not progress in the length direction and compared to the comparative example. It has extremely high adhesive strength and has a soft texture. In addition, regarding the traumatic nature of turning the lining material inside out and inserting it into the conduit, in the comparative example, trauma has already occurred in the coating layer even if the force of pulling the string-like material is small, but in the case of the present invention, damage is already caused to the coating layer. In this case, there was no injury even at 30 kg, which is excellent. The lining material of this invention is
Since the tubular woven fabric is woven with a twill weave structure, the weft threads do not come into contact with the burrs of the conduit, and the weft threads are less likely to be misaligned and pinholes are less likely to occur. Effects of the invention Therefore, according to the invention, the lining material is less likely to be damaged when inserted into a pipe, and the adhesive force between the covering layer and the tubular woven piece is strong, so that peeling does not occur. Therefore, an extremely excellent lining material can be obtained.

[Brief explanation of the drawing]

The drawings show one embodiment of the lining material of the present invention. 1... Lining material, 2... Tubular woven fabric, 3... Covering layer, 4... Warp, 5... Weft.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a lining material used in a lining method in which the lining material is inserted inside the pipe while being turned inside out using fluid pressure and bonded to the inner surface of the pipe via an adhesive, many weft threads are exposed on the outside surface. A pipe lining material characterized by forming a flexible synthetic resin coating layer on the outer surface of a tubular woven fabric made up of warp and weft yarns with a twill weave structure. 2. The lining material for a conduit according to claim 1, wherein the structure of the tubular woven fabric is a 1/2 twill structure on the outer surface. 3. The lining material for a conduit according to claim 1, wherein the structure of the tubular woven fabric is a 1/3 twill structure on the outer surface. 4. The pipe lining material according to claim 1, wherein the warp of the tubular woven fabric is a yarn formed by winding a synthetic fiber yarn around an elastic yarn. 5. The pipe lining material according to claim 1, wherein the weft of the tubular woven fabric is a thread formed by winding a synthetic fiber thread around an elastic thread. 6. The pipe lining material according to claim 4 or 5 of the utility model registration claim, wherein the elastic thread is a polyurethane elastic thread. 7. The pipe lining material according to claim 4 or 5, wherein the synthetic fiber yarn is a crimped synthetic fiber yarn. 8. The pipe lining material according to claim 1, wherein the weft of the tubular woven fabric is a crimped synthetic fiber yarn. 9. The lining material for a pipe according to claim 1, wherein the warp yarns of the tubular woven fabric are yarns made of polybutylene terephthalate fibers. 10. The pipe lining material according to claim 1, wherein the weft of the tubular woven fabric is a yarn made of polybutylene terephthalate fiber. 11 A yarn consisting of polybutylene terephthalate fiber is a crimped yarn,
A pipe lining material as set forth in claim 9 or 10 of the utility model registration claim. 12 Claims for registration of a utility model, characterized in that the weft of the tubular woven fabric is a yarn consisting of a mixed yarn of a crimped yarn of polyethylene terephthalate fiber and a crimped yarn of polybutylene terephthalate fiber. The lining material for the pipe line according to item 1.