管座焊缝内探法相控阵超声自动检测

Automated PAUT Technology of Nozzle Welds from Inside Access

介绍应用相控阵技术结合配有编码动作的机械装置,对插入式管座焊缝从接管内侧用线阵探头进行超声检测的方法。建立实验模型,可为声束全覆盖所必须考虑的物理参数,提供验证数据。建模和实测结果表明:利用声线跟踪法,扫查布置图(Scan plan)能提供所需覆盖范围的适当显示。当从接管内表面进行扫查时,用于引导探头扫查动作的机械装置往往可设计得减少复杂性。本文所述方法可望为承压设备结构较复杂的管座焊缝,实施超声相控阵检测(PAUT)符合ASME最新版要求提供有用借鉴。

This paper describes an ultrasonic inspection method for nozzle welds using phased-array techniques with mechanical apparatus that provides encoded motion from the inside surfaces of the set- through nozzle. Modelling provides evidence of the physical parameters that must be considered for full coverage. Modelled and actual results indicate that a scan-plan, using a ray-tracing program, can provide suitable indication of required coverage. In many cases, the mechanical apparatus used to guide the probe can be designed with a minimum of complexity when scanning access is from the inside surface of the noz- zle. The method could provide a useful reference for performing phased-array ultrasonic testing （PAUT） of nozzle welds with complex construction to meet the new requirements of ASME Code.