按“等强”原则设计的ＷＫ－４Ｂ挖掘机高强度变截面斗杆具有整体重量轻、装配工时少及维修频率低等优点。但由于斗杆是挖掘机的易损件且价格较高，故分析其损坏原因并合理地修复，可降低挖掘机的使用成本。 １　斗杆损坏的原因 斗杆在挖掘和重载回转时，反复承受拉、压、弯曲 According to the principle of “equal strength”, WK-4B excavator high strength variable section stick has the advantages of overall weight, less assembly man-hour and low maintenance frequency. However, because the stick is a vulnerable part of the excavator and the price is high, the reason for the damage is analyzed and repaired reasonably, which can reduce the use cost of the excavator. 1 stick damage reasons Stick excavation and heavy load rotation, repeatedly under tension, pressure, bending