Ultrasonic phased array detection method for polyethylene electric melting joint

Abstract

The invention provides a TOFD (Time of Flight Diffraction) detection method for a polyethylene hot-melt welding seam. The method comprises the steps: researching, developing and customizing a zero-degree water wedge block for water coupling, and employing the TOFD (Time of Flight Diffraction) technology; setting a focusing rule through an algorithm, and employing two broadband narrow pulse probeswhich are symmetrically distributed relative to the center line of a weld joint adopt a one-transmitting and one-receiving mode to detect a PE hot melting weld joint; employing a receiving probe for determining the position and the height of a defect in the weld joint by receiving the diffraction signal of the defect tip and the time difference thereof. The method can accurately quantify the defects of the hot melting weld joint, is high in detection success rate, can record and store the detection data, improves the safety of the polyethylene hot melting butt joint, and enables the detectionresult to have traceability.

Description

technical field [0001] The invention relates to the field of polyethylene electrofusion welding, in particular to an ultrasonic phased array detection method for polyethylene electrofusion welding joints. Background technique [0002] High-density polyethylene (HDPE) pipes have been widely used in municipal water supply networks, sponge cities, gas transmission, petrochemical and other fields due to their many advantages such as corrosion resistance, good shock resistance, light weight, and long service life. Based on a large number of studies and practical engineering applications of the American Society of Mechanical Engineers (ASME), HDPE pipes are very suitable for replacing the existing carbon steel pipes and plastic-lined steel pipes in the circulating water cooling system of nuclear power plants to solve the problem of seawater corrosion of carbon steel pipes and plastic-lined steel pipes. At present, hot-melt butt joints and electrofusion connections are generally us...

AI Technical Summary

Problems solved by technology

However, the following problems still exist in the conventional ultrasonic testing in the market at present: 1. The data of the testing results cannot be stored electronically, which leads to the inability to trace the source of the testing results, and subsequent traceability is very difficult; 2. Conventional ultrasound is usually displayed in pulses, and there are human interference factors in the testing process 3. Conventional ultrasonic testing results do not have a visual display function, and cannot quickly and intuitively reflect the cross-section status of the welded part. It is difficult to characterize the defect in time after the test is completed.

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