设计了环焊缝超声波扫查器导轨夹持行走机构。该行走机构采用带有凸缘的从动轮夹紧导轨，由类齿形主动轮与导轨啮合，驱动扫查器行走。为验证该行走机构的可靠性，设计并完成了与其原理完全一致的原理验证样机，同时进行了模拟扫查器沿环形导轨行走试验。试验表明，当自重24 kg对其施加600 N夹紧力时，行走机构能够可靠地沿环形导轨圆周运动。该行走机构原理验证样机为后续扫查器行走方案提供了可靠的依据。

An orbit-holding traveling mechanism of girth weld ultrasonic scanning equipment was designed in this paper. It held the orbit by engaged wheels with flange and drove the scanning equipment by a tooth-shaped driving wheel engaging with the orbit. In order to verify the reliability of this traveling mechanism, a prototype which works in the same way as the orbit-holding traveling mechanism was manufactured in this paper. And the experiment simulated the scanning equipment traveling along a orbit was completed, which showed that the traveling mechanism could travel along an orbit reliably when it weighed 24 kg and was exerted a 600N force. The prototype of traveling mechanism provided reliable evidence for the later traveling plan of scanning equipment.