The first is to cause the damage of the jack itself, causing major safety risks to its internal hydraulic system, if it is a mechanical jack, it will cause huge wear and tear to its screw, gear and other components, resulting in damage to the thread and ratchet, so that the whole jack scrap.

Then the damage of the supported object can be imagined, the jack lifting position is not right, it may lead to lifting target in the middle of the way suddenly out of the top cylinder, causing a crash, scratches and other situations.

Finally, it endangers the safety of the operator, falling in the process of midway use, and the operator may also suffer significant injuries because of dodging.