CN217157860U

CN217157860U - Improved demagnetizing device for spiral welded pipe

Info

Publication number: CN217157860U
Application number: CN202220693966.8U
Authority: CN
Inventors: 顾振军; 赵艺
Original assignee: Xinjiang Bagang Metal Product Co ltd
Current assignee: Xinjiang Bagang Metal Product Co ltd
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2022-08-09
Anticipated expiration: 2032-03-29

Abstract

The utility model discloses a modified spiral welded tube demagnetizer, this demagnetizer include that a diameter is 2020 cm's coil skeleton and 1 220V, 3 KVA's alternating current voltage regulator, 1 100A's rectifier bridge, control cable 19X 2.5 is 200 meters altogether, according to the winding method of coil, along coil skeleton clockwise winding set up 30 circles of coils, the end to end of control cable links to each other, the end to end access of reserving the coil the positive negative pole of rectifier bridge, coil winding twine 570 circles on coil skeleton. The utility model discloses direct current demagnetization device is applicable to the off-line demagnetization of spiral welded pipe, and the demagnetization of all specification spiral welded pipes can be solved to a coil, need not change a coil by every pipe diameter, greatly reduced electrician's work load. The demagnetization effect is good, the requirement of customers on the remanence of 0-15 gauss can be met, and no excess magnetic quality objection appears after the direct current demagnetization is replaced.

Description

Improved demagnetizing device for spiral welded pipe

Technical Field

The utility model relates to a modified spiral welded tube demagnetization device.

Background

When the steel pipe lines are welded in an opposite opening mode, the phenomenon of magnetic blow sometimes occurs to influence the whole welding process, welding can not be carried out in serious conditions, and the formation of the magnetic blow is the result of residual magnetism in the metal of the pipes. The main factors causing the remanence exceeding standard are two, one is that the remanence generated during the manufacturing of the steel pipe is too large and the demagnetization does not reach the standard, and the other is that a strong power supply line device is arranged nearby the steel pipe.

The process remanence is generated in the processing process of the spiral welded pipe, the single-wire submerged arc automatic welding current is about 800A, the remanence after welding is generally within 10A and does not need to be demagnetized, the welding current of the double-wire welding is more than 1000A, the remanence after welding is generally about 50 Gauss and has a standard of 30 Gauss, and customers require 15 Gauss, so that the steel pipe after the double-wire welding needs to be demagnetized in order not to influence the butt welding of steel pipes on site.

The demagnetization mode of the spiral welded pipe is off-line demagnetization generally, and the industry mostly adopts alternating current demagnetization to remove the remanence of the steel pipe. Ac degaussing coils have two problems to degauss:

1) the alternating current coil needs to be matched with a demagnetizing coil for demagnetizing each pipe diameter, the inner diameter of the demagnetizing star coil is 50-100mm larger than that of the steel pipe, the number of the demagnetizing coils is large, the inner diameter of the coil is 630-2020 mm, and can reach more than ten, and the demagnetizing coil needs to be replaced when the alternating current coil is produced and replaced every time the alternating current coil is replaced, which is very troublesome.

2) The demagnetization effect is poor, the remanence after demagnetization is generally 25-30 gauss, the standard requirements can be met, but the field welding requirements of customers cannot be met, the quality is much different, the problem that the remanence exceeds the standard is often solved on the field, and the reputation and the order of an enterprise are influenced. The AC demagnetization has the magnetic saturation phenomenon, and a 500 AC electric welder is usually used, the current is about 200A, and the residual magnetism can not be reduced when the current is increased, such as 300-400A.

The demagnetizing principle is that a magnetic field with the opposite direction to the residual magnetic field of the steel pipe is formed around the demagnetized pipeline, and the strength of the formed magnetic field is controlled by controlling the magnitude of the current so as to achieve the aim of demagnetizing. A coil consisting of flexible welding wires with the section of 35-50 mm is configured on a steel pipe to form a closed loop, one end of each of two welding wires is respectively connected with the anode and the cathode of a direct current welding power supply, the other end of each of the two welding wires is respectively connected with a metal plate fixed on a demagnetized pipeline, so that the action direction of a formed magnetic field is opposite to the action direction of a residual magnetic field of the steel pipe, and when demagnetization begins, the current can be adjusted to 80-100A. The result of the action of the demagnetizing field on the steel tube was periodically checked with increasing current (measured at power-on). If necessary, the current is controlled (generally by means of a current regulator) or its direction is changed (by means of changing the welding wire on the dc welding power source). After the demagnetization is finished, in order to smoothly reduce the magnetic flux, the current should be gradually reduced within lmin until zero value, and then the power supply should be cut off.

Disclosure of Invention

An object of the utility model is to provide a modified spiral welded tube demagnetization device, its simple structure, the demagnetization is effectual.

The utility model discloses a technical scheme be, a modified spiral welded tube demagnetizer, this demagnetizer include that a diameter is 2020 cm's coil skeleton and 1 220V, 3 KVA's alternating current voltage regulator, 1 100A's rectifier bridge, control cable 19X 2.5 is 200 meters altogether, according to the winding method of coil, along coil skeleton clockwise winding set up 30 circles of coils, the end to end of control cable links to each other, the end to end access of reserving the coil the positive negative pole of rectifier bridge, coil winding twines 570 circles on coil skeleton.

When the method is implemented, firstly, a remanence value of a produced steel pipe is measured by a gauss meter, then, a voltage regulator is modulated to AC50V, the steel pipe passes through a coil, then, remanence is measured, if the remanence does not reach an expected result, voltage is continuously added until the expected result is reached, from the practical verification condition, about 110V can meet the demagnetization requirements of almost all steel pipes, if the remanence is increased in the debugging process, the anode and the cathode are possibly reversed, the positive polarity and the negative polarity are adjusted, and after a direct-current demagnetizing coil is used, the remanence control range is 0-15 gauss.

The utility model discloses direct current demagnetization device is applicable to the off-line demagnetization of spiral welded pipe, and the demagnetization of all specification spiral welded pipes can be solved to a coil, need not change a coil by every pipe diameter, greatly reduced electrician's work load. The demagnetization effect is good, the requirement of customers on the remanence of 0-15 gauss can be met, and no excess magnetic quality objection appears after the direct current demagnetization is replaced.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings.

Fig. 1 is a schematic view of the connection structure of the present invention.

Detailed Description

An improved degaussing device for a spiral welded pipe is shown in figure 1 and comprises a coil frame 4 with the diameter of 2020cm, 1 alternating current voltage regulator 1 with the voltage of 220V and 3KVA, 1 rectifier bridge 2 with the voltage of 100A, control cables 3 with the specification of 19 x 2.5 and 200 meters, 2 photoelectric switches, and 30 coils are clockwise wound along the coil frame 4 according to the winding method of the coils, and the central axes of the 30 coils are coincident with the central axis of the coil frame 4. The control cable 3 is connected end to end, the end of the reserved coil is connected into the positive electrode and the negative electrode of the rectifier bridge 2, and the coil winding is wound on the coil framework 4 for 570 turns.

Claims

1. The utility model provides an improved spiral weld pipe demagnetizing device which characterized in that: the degaussing device comprises a coil framework with the diameter of 2020cm, 1 alternating current voltage regulator with the voltage of 220V and 3KVA, 1 100A rectifier bridge, and a control cable 19 x 2.5 which is 200 m in total, according to the winding method of the coil, 30 coils are clockwise wound along the coil framework, the heads and the tails of the control cable are connected, the heads and the tails of the reserved coils are connected into the positive and negative electrodes of the rectifier bridge, and 570 turns of coil windings are wound on the coil framework.