رافعة أرضية هيدروليكية

نظرة عامةA jack is a mechanical lifting device used to apply great forces or lift heavy loads. A mechanical jack employs a screw thread for lifting heavy equipment. A hydraulic jack uses hydraulic power.The most common form is a car jack, floor jack or garage jack, which lifts vehicles so that maintenance can be performed. Jacks are usually rated for a maximum lifting capacity (for example, 1.5 tons or 3 tons). Industrial jacks can be rated for many tons of load.In 1838 William Joseph Curtis filed a British patent for a hydraulic jack.In 1851, inventor Richard Dudgeon was granted a patent for a "portable hydraulic press" - the hydraulic jack, a jack which proved to be vastly superior to the screw jacks in use at the time.Hydraulic jacks are typically used for shop work, rather than as an emergency jack to be carried with the vehicle. Use of jacks not designed for a specific vehicle requires more than the usual care in selecting ground conditions, the jacking point on a vehicle, and to ensure stability when the jack is extended. Hydraulic jacks are often used to lift elevators in low and medium rise buildings.A hydraulic jack uses a liquid, which is incompressible, that is forced into a cylinder by a pump plunger. Oil is used since it is self lubricating and stable. When the plunger pulls back, it draws oil out of the reservoir through a suction check valve into the pump chamber. When the plunger moves forward, it pushes the oil through a discharge check valve into the cylinder. The suction valve ball is within the chamber and opens with each draw of the plunger. The discharge valve ball is outside the chamber and opens when the oil is pushed into the cylinder. At this point the suction ball within the chamber is forced shut and oil pressure builds in the cylinder.POWERFUL: Work with 12V vehicle power outlet, 5.0T(11000lb) jack capacity and 480N.M powerful torque.EFFICIENT: Lift the car in less than a minute by the jack, change a tire quickly.MUTILFUCTION: Jack, pump and LED Flashlight can meet multiple demands. Essential tool for outdoor emergency.CONVENIENT: The design of the jack is succinct and easy to operate , perfect car tire repair tool for car or SUV.SAFETY: The structure is stable and secure. Machine will stop working when it lifts beyond the height limit. You may also try to put a hand crank(not included) when lifter is working to enhance security.