A A visual position indicator for a screw jack can be provided in several ways. You can install digital position indicators on screw jacks or actuators if you need more precise position display. It can measure the rotations of the input shaft and display the corresponding position in the digital counter window. The display value per input shaft revolution is variable and is achieved through a series of gear reductions configured to accommodate different worm gear screw jack ratios, screw pitch, and travel length. Easy installation to existing actuators. All hand wheels are bored, keyed, and set-screw drilled to the proper dimensions.

A The standard End Fittings for Translating Screw Jacks includes: Threaded End, Clevis End, Top Plate, Fork End, Rod End, Plain End. These end fittings are available for machine screw jacks, ball screw jacks. As well as these standard end fittings we can also provide special designed fittings to suit your exact application needs.

A A Safety Nut Provides 2 Safety Roles: 1) In the event of excessive wear on the nut thread the load will be transferred from the standard nut to the safety nut. This will also provide visual wear indication as the gap between the safety nut decreases to zero as the standard lifting nut wears. 2) In the unlikely event of catastrophic nut thread failure the safety nut will sustain the load. Should the screw thread on the lifting nut or gear fail or wear out then the safety nut will support the load. The safety of industrial and human cargo is therefore improved. The safety nut can be used to monitor the wear on the lifting screw threads on the lifting nut (rotating screw jack) or worm gear (translating screw jack). As the lifting screw thread on the nut / gear wears the gap between the safety nut and the nut / gear reduces to zero. This allows for wear monitoring and scheduling of preventative maintenance before parts become worn out.

A Screw Jacks carry the load (compression or tension) axially along their lead screw. Either the “lead nut” for rotating screw jacks or worm gear for translating screw jacks is the mating part, which converts the rotary motion to linear motion. These two parts are also wearing components. Should the mating thread on these components fail then the load would either be completely or partially unsupported by the screw jack. Although generally this is a remote risk for some applications extra safety features are required to ensure that the screw jack can support the load even in emergency situations. A safety nut on a screw jack is an auxiliary nut, which follows the “lifting nut” on a rotating screw jack or the worm gear on a translating screw jack.

A Because of the efficiency of conventional worm gear screw jacks, the duty cycle is intermittent at rated load. At reduced loading, the duty cycle may be increased. The high performance ball screw jacks have higher thermal efficiencies due to their design allowing generally 30% higher duty cycles than conventional worm gear machine screw jacks.

A Screw jacks are designed primarily to raise and lower loads and any side loads should be avoided. The units will withstand some side loads, depending on the diameter of the lifting screw and the extended length of the lifting screw. Where side loads are present, the loads should be guided and the guides, rather than the screw jacks, should take the side loads - particularly when long raises are involved. Even a small side load can exert great force on the housings and bearings and increase the operating torque and reduce the life expectancy.

A Screw Jacks will operate in areas with vibration, however the vibration may cause the lifting screw to creep or inch down under load. For applications involving slight vibration, select the higher of the worm gear ratios. Should considerable vibration be present, use a drive motor equipped with a magnetic brake, which will prevent the screw jack from self-lowering (back-driving).

A Shock loads should be eliminated or reduced to a minimum, if they cannot be avoided, the screw jack model selected should be rated at twice the required static load.