(1) the bottom of the hydraulic jack used to match and tough. No grease Board to enlarge the bearing surface, and ensure safety. Unable to use iron instead of wood, to prevent sliding.
(2) when lifting for a smooth, weight slightly later to check for abnormalities, barring unusual circumstances can continue to rise. Shall be arbitrarily lengthened the handle or excessive action.
(3) do not overload, ultra-high. When the socket when there is a red line has been rated highly should stop lifting.
(4) hydraulic jacks in several jobs at the same time, a special command, make up or down simultaneously. Between adjacent two hydraulic jacks to support wood, ensure that interval to prevent sliding.