Method for manufacturing supersonic line focusing probe for small-diameter thin-wall steel tube flaw detection

Abstract

The invention relates to a method for manufacturing a supersonic line focusing probe for the small-diameter thin-wall steel tube flaw detection. The method which comprises supersonic line focusing probe key part material and parameter selection and concrete manufacturing process is characterized in that the supersonic line focusing probe key parts comprise an acoustic lens, a piezoelectric wafer and a damping block, wherein the material of the piezoelectric wafer is lithium sodium niobate, the material of the acoustic lens is synthetic glass, and the material of the damping block is a mixture of polysulfur rubber, an epoxy resin, tungsten powder and polyethylene diamine; and the concrete manufacturing process comprises the following steps: welding a piezoelectric wafer lead, bonding the piezoelectric wafer onto the acoustic lens, welding a ground wire, casting the damping block, and welding a firing wire to complete the manufacturing.

Description

technical field [0001] The invention belongs to the field of non-destructive testing, in particular to an ultrasonic line focusing probe for flaw detection of small-diameter thin-walled steel pipes. Background technique [0002] In the field of aviation, when ultrasonic inspection is performed on small-diameter thin-walled seamless steel pipes, the inspection requirements are in accordance with the "Instructions for Ultrasonic Inspection of Small-diameter Thin-walled Seamless Steel Pipes for Aviation" (HB / Z 75-83), hereinafter referred to as "Aerial Inspection manual". Requirements for the flaw detection system in the "Aerial Inspection Manual": 1. Use a liquid immersion point focusing probe with a working frequency of 5-10 MHz. In order to generate relatively pure shear waves in the pipe wall, the beam width at the point where the echo drops by 3 decibels is not large. It should be larger than one-half of the pipe wall; 2. The working sensitivity of the flaw detection syst...

AI Technical Summary

Problems solved by technology

[0003] However, in actual testing, liquid immersion line focusing probes are often used instead of liquid immersion point focusing probes for ultrasonic testing. The current 5-10 MHz liquid immersion line focusing probes on the market are designed for Φ8 when debugging the sensitivity of the flaw detection system. ×1, Φ10×1 steel pipes cannot meet the requirements in the "Aerial Inspection Manual": "The working sensitivity of the flaw detection system must be adjusted and verified with artificial damage standard sample tubes. The wave heights of internal and external damage should be as consistent as possible, and the difference should not be greater than 2 decibel” requirements

The existing ultrasonic line-focusing probes only consider conventional factors such as the frequency and focal length of the probe, and do not consider the special requirements for flaw detection of small-diameter thin-walled pipes, resulting in failure to meet the requirements of the "Aerial Inspection Manual"

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