Worm Gear Machine Screw Jacks

Worm Gear Machine Screw Jacks

Machine Screw Jacks - 1/4 Ton to 100 Ton & 5 kN to 200 kN

The Inch and Metric Worm Gear Machine Screw Jacks incorporate an alloy or stainless steel worm which drives a high strength bronze worm gear (drive sleeve). The worm shaft is supported on anti-friction tapered roller bearings with external seals provided to prevent loss of lubrication. The drive sleeve is supported on anti-friction tapered roller or ball thrust bearings. Rotation of the drive sleeve causes the acme thread lifting screw to translate or rotate, depending upon jack configuration.

The threads are precision formed, typically using Class 2-C (Centralizing) tolerances. Jack lift shaft lead tolerance is approximately ±0.004" per foot.

Worm Gear Machine Screw Jacks having gear rations between 20:1 and 32:1 are self-locking and will hold loads without backdriving in the absence of vibrations. All other ratios may require a brake to prevent backdriving.

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The jack housing is made of ductile iron and proportioned to support the rated capacity of the unit. The lifting screw is made of alloy steel with a minimum tensile strength of 95,000 psi.

Stainless Steel

All external components are manufactured from 300 series Stainless Steel materials. These jacks use a stainless steel worm with a high strength bronze drive sleeve.