厚壁无缝钢管纵向内壁缺陷超声波探伤方法的研究

Study on Ultrasonic Testing Method for Longitudinal Inner Surface Flaw of Heavy-wall Seamless Steel Tube

针对超声波检测时纯横波无法同时实现厚壁无缝钢管纵向内、外壁缺陷的检测,对无缝钢管超声波探伤入射角的允许范围进行计算,理论分析纯横波和变形横波探伤时所能检测的无缝钢管t/D范围,并给出纯横波和变形横波检测常规外径无缝钢管时的壁厚范围。分析认为:无缝钢管t/D≤0.20时采用纯横波对内、外表面进行探伤;0.20<t/D≤0.26时,应使用变型横波进行表面探伤,可解决厚壁无缝钢管纵向内壁缺陷检测的难题。

Addressing the problem that in case of the uhrasonic testing, using the pure transverse wave can not at the same time perform detecting longitudinal flaws on both inner and outer surfaces of the heavy-wall seamless steel pipe, permissible range of the UT incidence angle is calculated, and the seamless steel pipe t/D ranges as detected by the pure transverse wave and the deformed transverse wave are theoretically analyzed, and also the wall thickness range of seamless steel pipes with regular O.D. as detected with the pure transverse wave and the deformed transverse wave is presented. Based on the analysis result, it is concluded that for pipes with t/D≤0.20, the pure transverse wave should be used for detecting both inner and outer surface flaws, and for pipes with 0.20〈t/D≤O.26, the deformed transverse wave should be used for surface detection so as to realize detection of longitudinal inner surface flaw of the heavy-wall seamless steel pipe.