Experimental device for flexible closed-loop control over ERW pipe weld joint opening angles

Abstract

The invention discloses an experimental device for flexible closed-loop control over ERW pipe weld joint opening angles. The device comprises a high-frequency generator, an output device of the high-frequency generator, a CCD vidicon, a computer and five pairs of small rollers. Two electrode contacts are symmetrically fixed to a pipe blank located on a workbench with a weld joint as the center line, high-frequency currents form a circuit through the two electrode contacts and the pipe blank, the five pairs of small rollers are arranged in the manner that the appearance dimensions are gradually reduced in proportion and are sequentially in contact with the positions, at the two sides of the center line of the weld joint, of the surface of the pipe blank, and a pressure senor is mounted in a base below each small roller. The pressing amount of each pair of small rollers is changed by changing the axial distance and the radial distance between the pair of small rollers to obtain the opening angles different in size and shape. A closed-loop system is formed by the CCD vidicon, the computer and the pressure sensors, the precision of the sizes and shapes of the opening angles is guaranteed, optimal welding conditions can be obtained by carrying out experimental analysis on the sizes and shapes of the opening angles, and the quality of a welded pipe can be improved.

Description

technical field [0001] The invention relates to the field of ERW pipe welding, in particular to an experimental device for flexible closed-loop control of an opening angle of an ERW pipe weld seam. Background technique [0002] At present, ERW (Electric Rerisdance Welding) pipe welding generally undergoes rough forming and fine forming, and then directly applies high-frequency current for welding, and there are relatively few studies on the control of the opening angle of the weld. The opening angle is an important process parameter in the study of ERW pipe welding. A larger opening angle will reduce the heating efficiency and lengthen the required heating time; Generate strong electric sparks. At present, only a few special angles, such as 3°, 4.5°, and 6°, can be selected for experimental analysis and comparison in the research on the opening angle. The shape of the opening angle will also affect the quality of the welded pipe, usually the shape of the opening angle is V...

AI Technical Summary

Problems solved by technology

In the actual welded pipe workshop, due to the influence of comprehensive factors such as the fog generated by the coolant, the high temperature in the welding area, and the relative position restrictions between the roll and the tube blank, the shape of the opening angle cannot be obtained intuitively.

The yield point and tensile strength of the tube blank are very high. When the tube wall is thick, the resilience of the material is very large, so the expected size and shape of the opening angle cannot be guaranteed during production.

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