JPS6040264Y2 - Welded pipe inner bead cutting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved welded pipe inner surface bead cutting device that prevents the formation of a push-in eave on the inner surface of the pipe due to the pushing of welding spatter during the manufacture of welded pipes.

In recent years, there has been a method of manufacturing welded pipes by continuously forming metal strips such as steel strips or stainless steel strips into a circular shape using a group of forming rolls, and continuously welding both edges of the strips using high-frequency induction welding or high-frequency resistance welding. is being widely implemented.

In this manufacturing process, spatter is generated during welding and is scattered and adhered to the inner surface of the tube.

When cutting a bead generated on the inner welded portion of the welded pipe, the spatter is pushed into the inner surface of the welded pipe, causing indentation flaws.

Such push-in eaves also become a point of corrosion when used as a product.

In order to prevent this, an inner bead cutting device for welding spatter prevention material has been developed.

Regarding the above, the present applicant has provided a spatter-intrusion prevention device by rotatably mounting a receiving roller protruding from the outer circumferential surface of a rod inserted into the inside of a welded pipe, and surrounding the tip of the receiving roller. The inventor filed an application for development application No. 52-34424, which is a device that can move forward and backward in the radial direction of a welded pipe via a spring.

However, with this structure, spatter gets stuck in the gap of the sputter push-in preventer and becomes immovable, rendering the preventer useless and causing chatter in the rod.

As a result, problems remained, such as spatter damaging the inner surface of the tube and uneven biting of the inner bit into the inner beat, resulting in defective products.

This invention solves the above problems and has a simple mechanism.
It is an object of the present invention to provide an inner bead cutting device with a welding spatter intrusion prevention device that does not cause malfunction and has a long life.

An embodiment of the present invention will be described below based on the drawings.

In FIGS. 1 and 2, 1 is a welded pipe (hereinafter referred to as pipe), into which a metal strip is supplied while being formed into a circular shape.
The metal strip is tightened from the outer peripheral surface by a squeeze roll 2, and both edges of the metal strip are welded by a high frequency induction welder or a high frequency resistance welder W, and then continuously sent out in the P direction.

4 is a work coil that heats the metal strip during the welding, and 3 is spatter scattered around during the welding.

5 is a rod of an inner bead cutting device which is inserted into the pipe 1 and cuts the inner bead 6 generated on the inner surface of the welded portion of the pipe 1; 7 is the outer bead formed on the outer surface of the welded portion of the pipe 1; 8 is a rod External cutting tool 9 for cutting external bead 7
is fixed to the end of the rod 5 by a screw 9a, and the pipe 1
The inner cutting tools 10a, 10b, and 10c, each having a cutting edge with a radius of curvature that is approximately the same as the inner radius of the pipe 1, are receiving rollers rotatably mounted on the rod 5 so as to come into contact with the inner surface of the pipe 1.

These receiving rollers are pivotally supported by pins 10.

Reference numeral 11 denotes a spatter-intrusion prevention device mounted on the upstream side of the pipe delivery of each of the receiving rollers 10a, 10b, and 10c.

A push-in prevention device (hereinafter referred to as a prevention piece) 11 has a plate spring that is harder than the pipe bent into an L-shape so as to form a right angle in its natural state to form a mounting portion 11a and a baffle plate portion 11b.

The prevention piece 11 is attached to the mounting portion 11 with the baffle plate portion facing downstream.
a is fixed to the outer peripheral surface of the rod 5 by a mounting bolt 12.

The baffle plate portion 11a has at least the receiving rollers 10a, 10b, 1
The baffle plate portion 11b has a width equal to the width of 0c, its tip edge has a radius of curvature that is almost the same as the inner radius of the pipe 1, and the height of the baffle plate portion 11b is such that its tip portion contacts the inner peripheral surface of the pipe 1 Waist At this time, the angle A between the mounting part 11a and the obstructing part 11b is approximately 90
It is set to be between 1200° and 1200°.

For the prevention plate 11, in addition to metal, an elastic body such as a comb or plastic is used.

The baffle plate portion 11b may be shaped to have an arrowhead-shaped cross section in FIG. 3 or a radial cross-section in FIG. 4 facing upstream in the pipe traveling direction.

The prevention piece 11 has a mounting portion 11a and a baffle plate portion 11b.
In addition to the shape bent at 0 degrees, it may be bent at an angle greater than 90 degrees.

Alternatively, as shown in FIG. 5, it may be bent at an angle smaller than 90 degrees, and the mounting portion 11a may be attached to the downstream side of the obstructing portion 11b.

The inner bead 6 is formed by the device of the present invention having such a structure.
When this is cut, the baffle plate portion 11b of the prevention piece 11 is installed in contact with the inner circumferential surface of the pipe at the tip of the receiving rollers 10 a, 10 be 10 c protruding from the outer circumferential surface of the rod 5 on the upstream side of the pipe progression. Therefore, the spatter 3 scattered and attached to the inner circumferential surface of the pipe 1 is blown off to the side in the pipe traveling direction together with the cooling water introduced into the pipe.

Therefore, the sputter 3 receives the roller 10at 10bt.
The spatter 3 is not caught between the pipe 10c and the inner circumferential surface of the pipe, and no indentation damage to the pipe is caused by the spatter 3.

Then, the baffle plate portion 11b of the prevention piece 11 gradually wears out, but as the wear progresses, the angle between the baffle plate portion 11b and the mounting portion 11a approaches 900 due to the elastic restoring force, and during this period, the baffle plate portion 11b Spatter removal performance remains unchanged.

The prevention piece 11 can be easily replaced when worn and is inexpensive.

Experimental example: When cutting was performed using the inner bead cutting device according to Utility Model Application No. 52-34424, the preventer was used to cut pipes with a pipe feed length of 1000 to 2.
00077L caused malfunction, and the incidence of defective products due to uneven cutting depth reached 10 to 20%.

On the other hand, according to the internal bead cutting device of the present invention, the number of spatter indentation defects is zero, and the preventive tool has a pipe feed length of 60 mm.
Up to 00077L could be used, and the incidence of defective products was zero.

As described above, the welded pipe inner bead cutting device of the present invention, which is a welding spatter prevention tool, can easily remove spatter that is generated during welding and is scattered and adhered to the inner surface of the pipe by using the spatter prevention device with a simple structure. Therefore, when cutting the inner surface bead, the spatter is not pushed into the inner circumferential surface of the pipe by the receiving roller, and the occurrence of spatter intrusion flaws is prevented.

In addition, the spatter push-in prevention device of the present invention has no risk of malfunction and does not cause uneven biting of the internal cutting tool into the internal bead, which improves the acceptance rate of the product.

In addition, compared to conventional products, it is cheaper, easier to put on and take off, and has a much longer service life, providing great practical benefits.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a cutaway side view showing one embodiment of the present invention, Fig. 2 is a perspective view of the main part, and Figs. FIG. 5 is a plan view showing an example, and FIG. 5 is a side view of a main part showing still another embodiment. 1...Welded pipe, 2...Squeeze roll, 3...Spatter, 4...Work coil, 5...Rod, 6... ...Inner bead, 7...Outer bead, 8...Outer bite, 9...Inner bite, 10a, 10b. 10c... Receiving roller, 1 1... Spatter push prevention device, 1a... Mounting part, 1b... Baffle plate part.

Claims (1)

[Scope of utility model registration request] A rod is inserted into the welded pipe, a receiving roller whose tip comes into contact with the inner surface of the welded pipe is attached to the rod, and an inner cutting tool for cutting the inner bead is attached to the rod to cut the inner bead. In this device, a spatter-intrusion prevention device is installed on the upstream side of the welded pipe delivery side of the receiving roller, and the spatter-injection prevention device has a flat spring bent in a single-shape shape to connect the attachment portion to the rod and an obstacle for eliminating spatter. A welded pipe inner surface bead cutting device, characterized in that the baffle plate has at least the same width as the receiving roller and is attached such that its leading edge comes into contact with the inner circumferential surface of the welded pipe. .