JP2001047128A - Manufacture of pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a pipe joint in which the joint can be manufactured inexpensively, and piping work is easy. SOLUTION: In a manufacturing method of a joint 10, a substantially rectangular stainless steel plate having a specified thickness and partially arc-shaped notched parts on two edges opposite to each other in a longitudinal direction is drawn a plurality of times to form a curved pipe with the notched parts inside and to form a body part 10b, an end cylindrical part 10c larger in diameter than the body part is formed on each end of the body part 10b, the two edge parts 10a opposite to each other in the longitudinal direction are welded, and then, the body part 10b and the end cylindrical part 10c are pressed to truly circular. Since the joint is manufactured of the stainless steel plate, the joint 10 is inexpensive. Further, the straight pipes can be connected using an adhesive, and thus, the joint 10 can be easily connected to the straight pipe even by a regularly experienced worker.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a pipe joint such as a water pipe, and more particularly, to a method for manufacturing a pipe at one end or both ends, which has an end tube portion having a diameter larger than a diameter of a body portion as a central portion. And a method for manufacturing a pipe joint using a stainless steel plate.

[0002]

2. Description of the Related Art Conventionally, joints for pipe materials such as water pipes are:
There is one manufactured with a casting in which a screw is integrally formed on the inner surface of a large-diameter end tube portion. For example, in piping work, a straight pipe (connected pipe) end is threaded and screwed to the joint. Further, there is a conventional joint in which both ends are manufactured by castings having the same diameter as the straight pipe. In this case, welding is performed by joining the respective end faces of the joint and the straight pipe.

[0003]

The above-mentioned conventional joint is
Since threading is used, productivity is inferior, costs are high, and welding work must be performed at the time of plumbing work, and there is a problem that experienced technicians are required and construction costs increase. .

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a method of manufacturing a pipe joint which is inexpensive, can be easily connected to a straight pipe, and does not require any special technique. Aim.

[0005]

In order to achieve the above object, the present invention according to claim 1 has a predetermined thickness,
By drawing a plurality of times on a substantially rectangular stainless plate having arc-shaped notches at two opposing edges in the longitudinal direction, the pipe is formed into a pipe shape with the notches inward and curved. And, after molding the end tube portion having a larger diameter than the body portion at both ends of the body portion, welding the two edges facing each other in the longitudinal direction, and then, by press working, It is characterized in that the body and the end tube are molded so as to be corrected to a perfect circle.

According to a second aspect of the present invention, a substantially rectangular stainless plate having a predetermined thickness and having cutouts in the form of arcs at two opposing edges in the longitudinal direction is subjected to a plurality of drawing operations. By forming the body portion into a pipe shape with the notch portion inward and curved, and after molding an end tube portion having a larger diameter than the body portion at one end of the body portion, the longitudinal direction Are welded, and then formed by press working to correct the body and the end tube into a perfect circle.

[0007]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 11 of the accompanying drawings show an embodiment of the present invention. FIG. 1 is a perspective view of a first processed product in a process 1, and FIG. 2 is a perspective view of a second processed product obtained in a process 2. FIG. 3 is a perspective view of a third processed product obtained in step 3, FIG. 4 is a perspective view of a fourth processed product obtained in step 3, and FIG. 5 is a perspective view of a fifth processed product obtained in step 5. 6, FIG. 6 is a perspective view of a sixth processed product obtained in step 6, FIG. 7 is a perspective view of a seventh processed product obtained in step 7, and FIG. 8 is a perspective view of an eighth processed product obtained in step 8. 9 is a perspective view of a ninth processed product obtained in step 9, FIG. 10 is a perspective view of a finished product obtained in step 10, and FIG.
FIG. 3 is a perspective view showing a state where a straight pipe is connected.

The method of manufacturing the pipe joint 10 according to the present embodiment is a stainless steel stamped into a substantially rectangular shape having a predetermined thickness and having notches 1a, 1a in the form of arcs at two opposing edges in the longitudinal direction. By subjecting the plate 1 to a plurality of drawing processes, the plate 1 is formed into a curved pipe shape with the cutout portions 1a, 1a inside, and end tube portions 10c, 1 at both ends.
After molding 0c, the two opposite edges in the longitudinal direction are welded, and then the body 10b and the end cylinders 10c, 10c are molded by press working so as to correct them into perfect circles. That is.

Hereinafter, a process of processing a pipe joint, which specifically illustrates the above-described manufacturing method, will be described in detail with reference to FIGS.

(Step 1) A substantially rectangular stainless steel plate 1 having a predetermined thickness and provided with notches 1a, 1a formed in two opposite edges extending in the longitudinal direction and formed in a circular arc shape.
Is created by punching.

(Step 2) The stainless steel plate 1 is subjected to drawing to obtain a second processed product 2 having a bulged portion 2a formed at the center in the width direction (see FIG. 2).

(Step 3) The second processed product 2 is further subjected to a drawing process so that both edges 3 extending in the longitudinal direction are formed.
a and 3a are bent so as to form a slightly acute angle with respect to the bulging portion 2a side to obtain a third processed product 3 (see FIG. 3).
After this, trimming is performed.

(Step 4) By further drawing the third processed product 3, the bent portions 3a, 3a are extended, and both ends in the longitudinal direction are slightly further expanded than the expanded portions 2a. A fourth processed product 4 having the large end portions 4a, 4a is obtained (see FIG. 4). This end large diameter portion 4a,
4a is formed only in the vicinity of the top.

(Step 5) By further drawing the fourth processed product 4, the large-diameter end portions 4a, 4a at both ends in the longitudinal direction are expanded not only near the top but also over the entire end. A fifth processed product 5 having the end large diameter portions 5a, 5a is obtained (see FIG. 5).

(Step 6) The fifth processed product 5 is further drawn to obtain a sixth processed product 6 having bent portions 6a formed by bending both end edges extending in the longitudinal direction inward. (See FIG. 6).

(Step 7) The edges of the bent portions 6a, 6a (the edges provided with the notches 1a, 1a in Step 1) are joined by further drawing the sixth processed product 6. At the same time, there is obtained a seventh processed product 7 which is curved with the joint portion 7a inside, formed into a slightly angular pipe shape, and formed into end tube portions 7c, 7c having both ends larger in diameter than the body portion 7b. (See FIG. 7). When bending the joint 7a inside, a difference in the required amount of stainless steel material between the inside and the outside in the curved state of the seventh processed product 7 is generated, and the inside material is liable to be in a surplus state. The inconvenience does not occur due to the notches 1a, 1a provided in the stainless steel plate 1 in the step 1.

(Step 8) Next, the seventh processed product 7 is subjected to press working to obtain a circular pipe-shaped eighth processed product 8 (see FIG. 8).

(Step 9) Next, a ninth processed product 9 is obtained in which a welding 9a is applied to the joint of the eighth processed product.

(Step 10) Next, the ninth processed product 9 is subjected to press working to correct the end tube portions 10c, 10c and the body portion 10b into a perfect circular pipe shape. 10c and the body 10b are cut and finished to obtain a finished joint 10 having the end cylinders 10c, 10c and the body 10b (see FIG. 10). Note that reference numeral 10a
Is a weld.

As shown in FIG. 11, in the plumbing work for water supply or the like, after inserting straight ends of straight pipes 11 into the end tube portions 10c, 10c of the joint 10, the end tube portion 1 is inserted.
A brazing material (not shown) is poured into the gap between the pipes 0c, 10c and the straight pipes 11, 11, and the connection operation is completed. The work of pouring the brazing material is much easier than the conventional work of joining and welding end faces of a joint having the same diameter and a straight pipe.

As described above, in the method of manufacturing the pipe joint, the joint 10 is manufactured by using a relatively inexpensive stainless steel plate 1 and performing a plurality of drawing, pressing, and welding processes. In addition, the end tube portions 10c, 10c
After inserting the ends of the straight pipes 11, 11 into the pipes, the connection can be made by merely pouring a brazing material (not shown) into the gap between the end pipes 10 c, 10 c and the straight pipes 11, 11. At a water pipe plumbing site, there is no need to perform any work that can only be done by a technician who has experience of joining a straight pipe end to a joint end and performing welding, and is a worker with some experience There is an advantage that it can be easily connected.

The present invention is not limited to the means for manufacturing in the above-mentioned processing steps 1 to 10. For example, the end tube portion 10c is provided only at one end of the body portion 10b, and the other end is provided at the body portion 10b. May be stretched straight.
Further, the steps 2 to 7 for performing the drawing process include the notches 1a, 1a.
If it is made into a curved pipe with
The number of steps may be increased or decreased. Further, in order to connect the joint 10 to the straight pipes 11, 11, instead of using a brazing material, an adhesive is applied to the ends of the straight pipes 11, 11 and then inserted into the end cylindrical portions 10 c, 10 c of the joint 10. You may do so.

[0023]

As described above, according to the first aspect of the present invention, stainless steel is used as a material, and a plurality of drawing processes are performed.
Since the joint is manufactured through pressing and welding, the unit price is low, and after inserting the straight straight pipe end into the end tube part, the brazing material is poured into the gap between the end tube part and the straight pipe, or It can be connected simply by applying an adhesive to the end of the straight pipe and then inserting it into the end tube of the joint.For example, at the site of plumbing for water pipes, the end of the straight pipe is joined to the end of the joint and welded There is no need to perform construction that can only be performed by a technician who has the experience of performing such operations, and there is an effect that a worker with some experience can easily connect.

According to the second aspect of the present invention, since the joint is manufactured using stainless steel as a material and through a plurality of drawing, pressing, and welding processes, the effect of reducing the unit price is achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a first processed product in a step 1.

FIG. 2 is a perspective view of a second processed product in a process 2;

FIG. 3 is a perspective view of a third processed product in a step 3;

FIG. 4 is a perspective view of a third processed product in a step 3;

FIG. 5 is a perspective view of a fourth processed product in step 5.

FIG. 6 is a perspective view of a fifth processed product in step 6.

FIG. 7 is a perspective view of a seventh processed product in step 7;

FIG. 8 is a perspective view of an eighth processed product in step 8.

FIG. 9 is a perspective view of a ninth processed product in step 9;

FIG. 10 is a perspective view of a completed product in step 10.

FIG. 11 is a perspective view showing a state where a straight pipe is connected.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 stainless steel plate 1a cutout 2 second processed product 2a bulged portion 3 third processed product 4 fourth processed product 4a large end portion 5 fifth processed product 5a large end portion 6 sixth processed product 6a bent Part 7 Seventh processed product 7a Joined part 7b Body 7c, 7c End tube part 8 Eighth processed product 9 Ninth processed product 9a End tube part 9b Body 9b 10 Joint 10a Welded part 10b Body 10c End tube part

Claims (2)

[Claims] 1. A substantially rectangular stainless steel plate having a predetermined thickness and a circular arc-shaped notch at two opposing edges in a longitudinal direction is subjected to drawing processing a plurality of times so that the notch is formed inside. After forming a body part by making a pipe shape which is curved into a shape, and forming an end tube part larger in diameter than the body part at both ends of the body part, the two opposite edges in the longitudinal direction And then forming by press working to correct the trunk portion and the end tube portion into a perfect circle. 2. A substantially rectangular stainless steel plate having a predetermined thickness and having cutouts in the form of arcs at two opposing edges in the longitudinal direction is subjected to drawing processing a plurality of times so that the cutouts are formed inside. After forming a body portion by forming a pipe shape curved into a shape, and forming an end tube portion having a larger diameter than the body portion at one end of the body portion, there were two opposite edges in the longitudinal direction. A method for manufacturing a joint for pipe material, comprising welding a portion and then pressing the body and the end tube to correct the shape into a perfect circle by press working.