JP6934273B2 - Joint method of polyethylene double-layer pipe for water supply - Google Patents

Description

In the present invention, the resin is inserted into the joint body with the in-core press-fitted into the pipe end of the resin pipe (end diameter expansion pipe), and the female screw portion of the cap nut is screwed into the male screw portion of the joint body. It relates to a method of joining a polyethylene double-layer pipe for water supply that connects a pipe and a joint body.

The resin pipe connected by this type of resin pipe joint is JIS K6762 polyethylene two-layer pipe for water supply, and there are three types of one-type two-layer pipe, two-type two-layer pipe, and three-type two-layer pipe. The two-layer pipe is composed of an outer layer and an inner layer of polyethylene, and is classified as described above according to the outer diameter and the total thickness of the polyethylene two-layer pipe for water supply. Diameter 20 is equivalent to nominal diameter 13, nominal outer diameter 25 is equivalent to nominal diameter 20, nominal outer diameter 32 is equivalent to nominal diameter 25, nominal outer diameter 40 is equivalent to nominal diameter 30, nominal outer diameter 50 is equivalent to nominal diameter 40, and nominal outside The outer diameters of the 1st class double layer tube and the 2nd class double layer tube (diameter 63 is equivalent to the nominal diameter 50) are the same, but the overall thickness is different. It has a different relationship from the two-layer tube and the two-layer tube.

Conventionally, when the outer diameter and the overall thickness are different, various dedicated joint members have been manufactured and used for each of the joint body, the bag nut, the ring, and the in-core. Patent Documents 1, 2, 3 and the like exist as similar prior art documents regarding this type of resin pipe joint.

Japanese Unexamined Patent Publication No. 2009-79750 Japanese Unexamined Patent Publication No. 2004-52839 Japanese Unexamined Patent Publication No. 06-207964

Conventionally, there have been joints that enable connection by changing only the in-core for pipes having the same outer diameter and different overall thickness. Further, when the outer diameter and the overall thickness are different, the joint body, the bag nut, and the ring have been manufactured and corresponded to each dimension.

However, it takes a lot of labor and time to manufacture the joint body according to each dimension, and if this is shared according to other dimensions, there are many materials and other aspects. In particular, when renewing only the resin pipe that is joined to the existing water supply pipe or the like, the joint body can be used as it is.

For the three types of double-layer pipes, the diameter changes according to the outer diameter of the nominal diameter and the overall thickness, but since there is no difference in extreme changes, the diameters of the bag nut, ring, and in-core are changed. It is conceivable to make the best use of the joint body by adjusting it according to the change of.

Furthermore, when the joint body is compatible with three types of double-layer pipes, the specifications of the male screw to be screwed with the female screw of the cap nut change according to the change in the outer diameter of the nominal diameter and the overall thickness, so that the joint body For molding, a new mold corresponding to the type 3 double-layer pipe is required, and the cap nut also requires a female screw specification to be screwed with the male screw of the above joint body, and a new mold corresponding to the type 3 double-layer pipe is required. A mold is required, which requires a large amount of cost and labor as compared with the case where the joint body is shared, and there is also a problem that the selection of members at the time of joining work becomes complicated.

An object of the present invention is to deal with each of the problems of the three types of double-layer pipes, absorb the change in diameter by adjusting the bag nut, the ring, and the in-core, and make the best use of the joint body. Is to be.

The present invention is intended to address the above-mentioned problems, and is used in a joint body provided with a resin pipe fitting recess in which a male screw screwing with a female screw of a cap nut that presses and screwes the tail end of a ring is engraved on the outer circumference. On the other hand, by using the opening diameter of the closed end of the cap nut and the diameter of the ring and the in-core corresponding to the outer diameter and the overall thickness of the three types of two-layer pipes, it is possible to correspond to each of the three types of two-layer pipes. , It is made to be able to join efficiently.

With this configuration, for three types of double-layer pipe joints with different outer diameters and overall thickness, the closed end is opened without preparing a joint body with different specifications and without changing the female screw specifications. It is possible to correspond to each double-layer pipe joint by using a bag nut that corresponds only to the diameter, a ring that corresponds to the outer diameter and the diameter corresponding to the total thickness, and an in-core.

In the present invention, in JIS K6762 polyethylene two-layer pipe for water supply, three types of joint members different from each other depending on the difference in outer diameter and overall thickness of the first type two-layer pipe, the second type two-layer pipe, and the third type two-layer pipe are prepared. By standardizing the joint body, it is possible to avoid the waste of material manufacturing and the complicated diversification of the number of parts, which had to be dealt with, and to save a lot of materials and rationalize the joint work. be.

An embodiment of the present invention is shown, in which an in-core is press-fitted into the fitting recess of the joint body to expand the diameter and fitted into the end of a two-layer pipe through which a bag nut and a ring are inserted, and screwed with a bag nut. A vertical sectional front view showing. Similarly, an exploded vertical sectional front view showing the relationship of each member of FIG. 1 in an exploded state. Similarly, in the comparison diagram showing the outer diameter, overall thickness, outer layer, and inner layer of the JIS K6762 polyethylene double-layer pipe for water supply, (A) is a type 1 double-layer pipe, (B) is a type 2 double-layer pipe, and (C) is. It is a cross-sectional view of the type 3 two-layer pipe. Similarly, another embodiment of the ring is shown, where (A) is a front view, (B) is a right side view, and (C) is an XX sectional view of (B). Similarly, a vertical cross-sectional front view showing a double-layer pipe screwing state of a resin pipe joint using the ring of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Reference numeral 1 denotes a joint body called a body, which is provided with a resin pipe fitting recess 12 in which a male screw 11 screwed with a female screw of a bag nut 3 for pressing and screwing the tail end of the ring is engraved on the outer circumference.

Reference numeral 2 denotes a polyethylene double-layer pipe for water supply to be joined, which is classified by JIS K6762 into a type 1 double-layer pipe, a type 2 double-layer pipe, and a type 3 double-layer pipe, and further, each of the three types of double-layer pipes. Specifications for the outer diameter 23, the overall thickness 24, the outer layer thickness 25, the reference inner diameter 26, and the reference inner layer thickness 27 are defined for each nominal diameter.

For example, in the case of a nominal diameter of 25, for a type 1 double-layer pipe, the standard outer diameter is 34.0, the average outer diameter tolerance is plus or minus 0.20, the overall thickness is 5.0, and the overall thickness tolerance is plus. -It is minus 0.35 and the reference inner diameter is 24.0.

Regarding the type 2 double-layer pipe, in the case of the same nominal diameter of 25, the standard outer diameter is 34.0, the average outer diameter tolerance is plus or minus 0.20, the overall thickness is 3.5, and the overall thickness tolerance. For plus / minus 0.30, reference inner diameter 27.0, type 3 double-layer pipe, if the nominal outer diameter is 32 (equivalent to nominal diameter 25), the standard outer diameter is 32.0 and the average outer diameter tolerance is plus 0. The total thickness is .30, minus 0, the total thickness is 2.9, the tolerance of the total thickness is plus 0.5, minus 0, and the reference inner diameter is 25.7.

As described above, since there is a slight difference in outer diameter and overall thickness for each of the three types of two-layer pipes, conventionally, joint members having different specifications for each of the three types of two-layer pipes have been manufactured. It has corresponded. However, manufacturing members with different overall specifications for each type requires designing multiple types of specifications from the mold, and manufacturing and sorting members with different specifications for each nominal diameter, which takes a lot of time. It was laborious.

In particular, the male screw of the joint body has a large number because the overall specifications will change due to the difference in the diameter of each two-layer pipe to be connected, and the female screw specifications of the bag nut to be screwed to this will also change. In addition to the need for a mold for the above, care must be taken when selecting screw specifications.

The present invention uses the joint body of a type 1 double-layer pipe, a type 2 double-layer pipe, and a type 3 double-layer pipe having the same nominal diameter, so that at least each of the three types of double-layer pipes has a joint body standard. Avoiding multiple specifications, avoiding multiple female thread specifications for the cap nuts that are combined with this to form resin pipe joints, and minimizing changes in each of the three types of double-layer pipes. It is a thing.

That is, when the nominal diameter is 25, the standard outer diameters of the type 1 double-layer pipe and the type 2 double-layer pipe are both 34 mm, and the reference inner diameter of the type 1 double-layer pipe is 24 mm, and the reference inner diameter of the type 1 double-layer pipe is 24 mm. The reference inner diameter of is 27 mm, which causes a difference of about 3 mm, but when viewed as a screw specification, it is dispersed by about 1.5 mm up and down, and the diameter is expanded by in-core press fitting and adjustment by loading the fastening ring. It is within the acceptable range for screwable screw specifications.

In the case of a nominal diameter of 25, the standard outer diameter of the 1st class 2 layer tube and the 3rd class 2 layer tube is 34 mm for the 1st class 2 layer tube and 32 mm for the 3rd class 2 layer tube, which is a difference of 2 mm, reference. The inner diameter is 24 mm for the type 1 double-layer pipe and 25.7 mm for the type 3 double-layer pipe, which causes a difference of about 1.7 mm, but when viewed as a screw specification, the outer diameter is about 1 mm up and down. The inner diameter is dispersed up and down by about 0.85 mm, and the diameter is expanded by in-core press fitting and adjusted by ring loading, which is within the permissible range as a screwable screw specification.

Furthermore, in the case of a nominal diameter of 25, the standard outer diameter of the type 2 double-layer pipe and the type 3 double-layer pipe is 34 mm for the type 2 double-layer pipe and 32 mm for the type 3 double-layer pipe, which is a difference of 2 mm and an inner diameter. The type 2 double-layer pipe is 27 mm, and the type 3 double-layer pipe is 25.7 mm, which causes a difference of about 1.3 mm, but when viewed as a screw specification, the outer diameter is about 1 mm above and below. The inner diameter is dispersed up and down by about 0.65 mm, and the diameter is expanded by in-core press fitting and adjusted by ring loading, which is within the permissible range as a screwable screw specification.

To respond to changes in members other than the joint body, first, for the bag nut 3, the opening 32 of the bag-side closing end 31 of the nut has a diameter corresponding to the outer circumference of the applicable two-layer tube. Absorbs the difference in diameter.

For the ring 4 and the in-core 5, the diameter difference between the joint body 1 and the applicable double-layer pipe is absorbed by adjusting the diameter according to the outer diameter and the overall thickness of the applicable double-layer pipe, and the opening diameter of the cap nut is absorbed. In combination with fixing the outer peripheral peripheral surface of the applied double-layer pipe of 32, the outer peripheral peripheral surface of the applied double-layer pipe can be properly screwed by the joint body 1.

Next, an example of screwing the outer peripheral peripheral surface of the applied two-layer pipe by the joint body 1 will be described. First, the bag nut 3 and the ring 4 are inserted into the applicable double-layer pipe 2, and the in-core 5 is press-fitted to the end flange 51 at the end of the applicable double-layer pipe 2 on the fitting side to the joint body to expand the diameter and the joint. It is fitted into the resin tube fitting recess 14 of the main body.

Further, by screwing and screwing the female screw 33 of the bag nut 3 and the male screw 11 of the joint body 1, the closing end 31 of the bag nut pushes the tail end of the ring 4, and the inner wall of the resin pipe fitting recess 14 of the joint body The ring 4 is propelled in the gap around the outer shell of the expanded joint double-layer pipe 2, and the joint double-layer pipe 2 is screwed into the resin pipe fitting recess 14 of the joint body 1.

FIG. 4 shows another embodiment of the ring 4, and is a gap between the opening diameter of the closing end edge 32 of the bag nut and the diameter difference of the outer peripheral peripheral surface of the joint double-layer pipe 2 at the tail end portion 41 of the ring 4. An auxiliary frame 42 was attached to fill the space.

By attaching the auxiliary frame 42, together with the interrupt 43 set on the tail end side of the ring 4, the diameter difference between the inner diameter of the closed end edge 32 of the cap nut and the outer peripheral peripheral surface of the joint double-layer pipe 2 as shown in FIG. It was possible to smoothly absorb the above-mentioned material and suppress rattling due to the diameter difference between the diameter of the joint body 1 and the diameter of the joint double-layer pipe 2.

The method for joining the resin two-layer pipe for water supply according to the present invention is the JIS K6762 polyethylene two-layer pipe for water supply, which is generated from the difference in outer diameter and overall thickness. Avoiding the hassle of having to prepare three different types of joint members for double-layer pipes, and using the joint body for both purposes has brought about significant labor savings and rationalization in terms of materials and labor. It can be used.

1 Joint body 11 Male screw screwed with the female screw of the cap nut on the secondary side of the joint body 12 Resin pipe fitting recess of the joint body 2 Applicable two-layer pipe 21 Applicable two-layer pipe outer layer 22 Applicable two-layer pipe inner layer 23 Applicable two-layer Outer diameter of pipe 24 Overall thickness of applicable two-layer pipe 25 Outer layer thickness of applicable two-layer pipe 26 Reference inner diameter of applicable two-layer pipe 27 Reference inner layer thickness of applicable two-layer pipe 3 Bag nut 31 Bag side closure of bag nut End 32 Opening diameter of the bag-side closing end of the bag nut 33 Female thread of the bag nut 4 Ring 41 Ring tail end 42 Ring auxiliary frame 43 Ring interrupt 5 Incore 51 Incore end flange

Claims (2)

The end of the bonded resin pipe is expanded with an in-core by the joint body, bag nut, ring, and in-core of the type 1 double-layer pipe, the type 2 double-layer pipe, and the type 3 double-layer pipe having the same nominal diameter in the polyethylene double-layer pipe for water supply. In the resin pipe joint where the bag nut is screwed to the joint body after the diameter is adjusted, the opening diameter of the bag-side closed end of the bag nut, the ring diameter of the ring, and the core diameter of the in-core are set to each of the above three types of two layers. A method for joining a polyethylene double-layer pipe for water supply, which comprises making the joint main body of the above three types of resin double-layer pipe joints have the same specifications by making them correspond to the outer diameter and the overall thickness of the pipe. .. The polyethylene two-layer for water supply according to claim 1, wherein an auxiliary frame is attached to the tail end of the ring to fill the gap due to the difference between the inner diameter of the closed end edge of the cap nut and the outer peripheral peripheral surface of the applicable two-layer pipe. Pipe fitting method.

Images