JPS63238449A - Apparatus for detecting welding flaw - Google Patents

Abstract

PURPOSE:To easily and certainly detect a welding flaw, by revolving an arm by bringing the detection part pressing a welded part into contact with the welding flaw part. CONSTITUTION:A rotor 7 is brought into contact with a welded part 20a to horizontally arrange an arm 1. In this state, the rotor 7 is pressed to the welded part 20a by the wts. of a wt. 16 and a control wt. 17. A metal pipe 20 moves in the longitudinal direction thereof with the advance of welding work and the rotor 7 rotates in the state brought into contact with the welded part 20a by the movement of the metal pipe 20. At this time, when a welding flaw part is present in the welded part 20a, the rotor 1 is brought into contact with the welded flaw part to revolve the arm 1. A projection 9 is brought into contact with a detection bolt 11 by the revolution of the arm 1 to allow a current to flow to an alarm lamp 4 and the alarm lamp 4 lights. By the lighting of the alarm lamp 4, a worker can know the presence of the welding flaw.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an apparatus for detecting welding defects that occur when a long metal pipe is manufactured by seam welding.

``Prior art'' As an example of a method for manufacturing long metal pipes, a metal tape manufactured by roll forming or the like is used, and the ends of the metal tape are brought together and continuously seam welded. Techniques for manufacturing pipes are known. The presence or absence of weld pinholes and defects occurring in the welded portion of the metal tape is inspected by a flaw detection method using an eddy current flaw detector or the like, or by a visual inspection using a fiberscope or the like.

``Problems to be Solved by the Invention'' However, all of the conventional welding defect detection methods described above have the disadvantage of requiring expensive equipment.
There were drawbacks such as the need for skill to detect welding defects because the sensitivity settings of the equipment during flaw detection were complicated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a welding defect detection device that can reliably detect welding defects, has a simple configuration, is inexpensive, and is easy to implement. do.

"Means for Solving the Problems" In order to solve the above problems, the present invention provides an arm that is swingably supported by a support member, and a seam welding of a metal pipe that is attached to one end of the arm. a detection member pressed by the arm; a detection end formed at the other end of the arm; a detection unit installed near the detection end to detect movement of the detection end as the arm swings; It is equipped with a warning device activated by this detection section.

``Function'' Since the welding part is pressed by the detection member, when the detection member reaches the welding defect, fluctuation occurs in the welding defect, which causes the arm to rotate and the detection end to move. The detection section detects this movement of the detection end and activates a warning device to warn of the existence of a welding defect.

"Embodiment" The drawing shows an embodiment of the present invention, and the detection device A of this embodiment includes a rod-shaped metal arm l, and this arm l.
a triangular prism-shaped support member 2 that supports a portion near the tip (left end in the drawing) and serves as a fulcrum of the arm I; a detection section 3 provided on the rear end side of the arm I; It is mainly composed of a warning lamp (warning device) 4 connected to.

A thick head portion 5 is formed at the tip of the arm 1, and a wheel-shaped rotor (detection member) 7 is provided in a recess 6 formed on the lower surface of the head portion 5. The rotor 7 is supported by a support shaft 8 inside the recess 6 so as to be rotatable along a plane perpendicular to the axis of the arm 1.
The outer peripheral portion of the rotor 7 is made to protrude outward from the recess 6. In addition, a projection (detection end) 9 is provided on the upper surface of the rear end of arm l.
is formed.

Furthermore, a support plate 10 in which a screw hole is formed is provided above the projection 9 of the arm l, and a bolt-shaped detection terminal 11 is screwed into the screw hole, and the tip of the detection terminal 11 is screwed into the screw hole. It is brought close to the protrusion 9 of one arm 1. Also,
A warning lamp 4 is electrically connected to the detection terminal 11 via a connecting line 13, and a part of the arm l is electrically connected to the warning lamp 4 via a power source 14 via a connecting line 15. There is.

On the other hand, a weight 16 is removably installed on the upper surface of the head portion 5 of the arm I, and an adjustment weight is attached to the threaded portion 1a formed in the center of the arm I. 7 is attached so that the adjustment weight I7 can be moved along the threaded portion 1a.

Next, the operation of detecting welding defects using the detection device A having the above configuration will be explained.

What is indicated by the reference numeral 20 in the drawings is a metal pipe made by seam welding metal tape. This metal pipe 20
To detect a welding defect, the rotor 7 is brought into contact with the welded part 20a and the arm 1 is installed horizontally. In this state, weight 1
6 and the weight of the adjusting weight 17 press the rotor 7 against the welding part 20g.

On the other hand, the metal pipe 20 is moved in its length direction as the welding work progresses, and as the metal pipe 20 moves, the rotor 7 rotates while coming into contact with the welding part 20a. At this time, if a welding defect exists in the welding portion 20a, the rotor 7 comes into contact with the welding defect, causing the arm 1 to rotate. This arm! As a result of the rotation, the protrusion 9 comes into contact with the detection bolt 11, and as a result, current flows through the warning lamp 4 and the warning lamp 4 lights up. The lighting of this warning lamp 4 allows the operator to know the existence of a welding defect. In addition, the rotor 7
When the metal pipe 20 moves under pressure, the rotor 7 rotates to reduce the contact resistance between the metal pipe 20 and the weld 20a. There isn't.

In addition, in order to cope with the detection of various welding defects, the ratio of the distance a between the rotor 7 and the fulcrum of the arm 1 and the distance s between the fulcrum and the protrusion 9 of the arm 1 is adjusted. This is handled by adjusting the amplification ratio of the amount of vertical movement of the rotor 7. Further, the contact pressure of the rotor 7 against the welding part 20a can be varied by changing the weight 116 and the position of the adjustment weight 17, and the sensitivity can be adjusted arbitrarily by changing the screw-in length l of the detection terminal 11. Can be set.

Furthermore, when seam welding the metal pipe 20, the linear speed of the metal pipe 20 is set to various values, but when the linear speed is changed, the weight of the weight 16 and the position of the adjustment weight 17 must be adjusted. Alternatively, changes in the linear velocity can be easily accommodated by changing the ratio between Ha and distance S, or by changing the screw length 1 of the detection terminal ti. The detection unit RA is mainly composed of an arm 1 that rotates depending on the presence or absence of a welding defect, a detection unit 3 that detects the rotation of the arm 1, and a warning device 4. Since there are fewer electrical parts than other devices, there is a low possibility of failure, and the equipment is inexpensive and easy to implement.

Incidentally, in the embodiment described above, the warning lamp 4 is used as the warning device, but the warning device may be a sound wave generator such as a buzzer, or other devices may be used. Further, since the rotor 7 may have a configuration that reduces contact resistance with the welded portion 20a, it does not need to be wheel-shaped, and may be spherical or the like. Furthermore, in the above embodiment, an example in which the arm 1 is installed horizontally has been described;
If the arm l is pivoted by a support member, it is also possible to detect welding defects by swinging the arm l in an upright state.

``Effects of the Invention'' As explained above, the present invention is configured so that the arm is rotated when the detection unit that presses the weld comes into contact with the weld defect, and the rotation of the arm is detected by the detection unit. Unlike conventional devices that use flaw detectors, the device uses a contact method to detect welding defects, making it possible to reliably detect welding defects without causing detection errors. Since it is easy to handle, it has the effect of improving reliability when detecting welding defects. In addition, the device of the present invention is mainly composed of an arm that rotates depending on the presence or absence of a welding defect, a mechanism for detecting the rotation of the arm, and a warning device, and is more electrical than a detection device using a flaw detector. Since there are only a few parts, there is a low possibility of failure, and the equipment is inexpensive and easy to implement.

[Brief explanation of drawings]

The drawings are schematic diagrams showing one embodiment of the present invention. A: Detection device, old arm,
2...Support member, 3...Detection section, 4...Warning device (warning lamp), 5...
...Head part, 6...Recessed part, 7.
...Rotor (detection member), 8...Support shaft, 9...Protrusion (
detection end), lO... support plate, 11...
...Detection terminal, 13.15...Connection line,
14...Power supply, 20...Metal pipe,
20a...Welding part.

Claims (1)

[Claims] an arm that is swingable about a portion supported by a support member as a fulcrum; a detection member that is provided protruding from one end of the arm and is pressed against a seam weld of a metal pipe; A detection end formed at the end, a detection part installed near the detection end to detect movement of the detection end as the arm swings, and a warning device activated by the detection part. A welding defect detection device characterized by: