一、概述某单位使用的一台180匹马力推土机,系日本小松制作所生产的 WD140—4型。施工中由于十字头紧固螺丝松动滑脱,将变速箱壳体击裂,裂纹总长约850毫米,处于仰、仰角焊位置,见图1。其中,仰角焊位置裂纹长约400毫米,且在仰位裂 First, an overview of a unit used by a 180 hp bulldozer, the Department of Japan’s Komatsu production WD140-4 type. Construction due to cross-head screws loose slippage, the gearbox cracked, the total crack length of about 850 mm, at Yang, Yang angle welding position, shown in Figure 1. Among them, the angle of crack location crack location about 400 mm, and in the subsidence crack