门式起重机的悬臂上翘度是一项重要的安全性能指标,直接影响起重机的安全运行。当上翘度过小,甚至在水平线以下(下沉),负载小车由悬臂端向支腿方向运行时,会使悬臂进一步下挠而出现坡度。小车运行机构不仅要克服小车的正常运行阻力,还要克服由于轨道斜坡而产生的爬坡附加阻力,将导致小车运行机构的使用寿命降低,甚至损坏机构,烧坏电动机。当小车由支腿向悬臂方向运行时,还会因有斜坡而出现“打滑”现象,自行滑车,影响起重机安全正常工作。此外,悬臂下沉会使悬臂箱体上盖板和腹板上半部的拉应力加大,严重下挠时甚至形成裂纹及产生脱焊。所以,在进行门式起重机的检验时,对上翘度进行正确的检验和判断 The gantry crane cantilever is an important safety performance index, a direct impact on the crane’s safe operation. When the upturned is too small, even below the level (sink), when the trolley runs from the cantilever end to the leg, the cantilever will be further down-scratched to show the grade. The trolley operating mechanism not only needs to overcome the normal running resistance of the trolley, but also overcomes the additional resistance of the hill climbing caused by the rail ramp, which will lead to the reduction of the service life of the trolley operating mechanism, even damaging the mechanism and burning the motor. When the trolley runs from the outrigger to the cantilever, the phenomenon of “slipping ” occurs due to the slope, and the trolley is caused to slide by itself to affect the safety of the crane. In addition, the cantilever subsidence will increase the tensile stress on the upper cover and the upper half of the cantilever box, and even crack and produce desoldering even under severe flexing. Therefore, in the gantry crane inspection, the correct degree of uplift test and judge