Unlike a hydraulic jack, a screw jack uses only the force of the handle to lift the load. This makes it much simpler to program and tune. A screw jack can also be self-locking in case of power loss. They are used for mechanical lifting, alignment, and load positioning. They can be used in industrial applications and in the aerospace and metallurgical industries. They can be powered by an electric motor or a hydraulic motor. They can also be equipped with a drive controller, encoder, and potentiometer. They can be connected to a gearbox, coupling, or a bevel gearbox. They are suitable for use in high temperature and corrosion/explosion proof environments.
Screw jacks can be classified into three types: worm gear, ball, and anode. Each type has a different set of advantages. For example, worm gears have lower speeds and less efficiency than other types, but they are best for lifting applications. The anode jack has larger bearings and can handle side-loading stress. Anode jacks are also ideal for applications that involve temperatures above 200 deg. The worm gears are made from wear-resistant bronze and have heavy duty seals to protect against alumina dust. They are also larger than other screw jacks.
The worm gear screw jack is best for lifting applications that do not occur often. The jack is not designed to be as efficient as other types. This is one reason why it is not used in many applications. The other main advantage of the worm gear is that the jack does not require an ancillary hydraulic system. It can be used for a variety of applications, including synchronizing the movement of a blade in wind turbines. It can also be used for lifting oven hoods, roll stands, and other equipment.
Another type of screw jack is the wedge jack. This design is designed to prevent the screw from spinning. It also eliminates the need for storage for the movement of the screw. This design is also used to provide upward or downward motion of the screw. The housing of the wedge jack can be either cast or foot-mounted. It can also be supplied with protective bellows.
A screw jack can be powered by an electrical motor or a hydraulic motor. An electric motor can be mounted directly to the actuator’s worm shaft through a coupling. An auxiliary power source such as a hand wheel can be used as well. It is recommended that a brake be used to prevent over travel when the motor is switched off.
Screw jacks are available in a wide range of models and styles. Some of the most common screw jacks include the standard form, the keyed screw jack, and the traveling nut jack. They can be used in a variety of applications, including high-speed locomotive maintenance and solar photostatic. They are also commonly used for packaging equipment and scaffolding pipes. They can be used in a number of markets, including water processing, pharmaceutical equipment, and steel works.