在发动机的修理中 ,有为数不少的驾驶员和修理工不了解缸盖螺母拧紧后还要进行一次重复拧紧 ,有的虽进行重复拧紧 ,但复紧时间和方法不当 ,导致不应有的故障和损坏。缸盖螺母为何拧紧后要再次拧紧呢 ?首先 ,因为缸垫是由耐热石棉制成的 ,具有一定的弹性。缸垫是靠自身的弹力而 In the engine repair, there are a large number of pilots and mechanics do not understand the cylinder head nut after tightening but also to repeat a tighten, although repeated tightening, but the tightening time and method is improper, resulting in unforeseen failures And damaged. Why tighten the cylinder head nut tighten again? First of all, because the cylinder head gasket is made of heat-resistant asbestos, with a certain flexibility. Cylinder pad is by its own elasticity