Editorial Technical Reference

Screw-driven lifting mechanism (screw jack lift) for machines

Screw-driven lifting mechanisms for machines · Trapezoidal versus ball screw efficiency, self-locking and brakes, duty cycle, load and drive power

A screw-driven lifting mechanism is the vertical axis of a machine: a platform, plate or carriage guided by columns or rails and moved by one or more lead screws, ball screws or screw jacks driven by a geared motor. It positions drums, tools, moulds or workpieces at a set height inside automated equipment. Ask three things first: whether the screw must hold the load without power (self-locking) or needs a brake, how often and how fast it moves (duty cycle), and what load, stroke and positioning accuracy it must achieve.

Lead-screw, ball-screw and screw-jack lifting mechanisms with guides and drives built into machines and automated systems, including drum and container lifts, tool and mould lifts and lifting platforms inside equipment. Drum tumblers and rollers that mix sealed drums are covered on the Automated chemical drum agitation and homogenization system page. Hoists, forklifts, scissor lift tables and hydraulic cylinders sold alone are outside this page.

CNFX editorial research · Sources checked October 12, 2026 · 3 sources

Choose trapezoidal or ball screw Size load, duty and drive

Four-column machine frame with a central vertical lifting screw under a heavy steel plate, two yellow chain hoists above and an engineer in a hard hat holding a handheld controller — Screw-driven lifting frame inside a machine

Start with your task

Choose trapezoidal or ball screwEfficiency and self-locking. Size load, duty and drivePower and duty cycle.

Choose a trapezoidal or ball screw: efficiency and self-locking

ZIMM explains that, depending on gear ratio, screw lead and lubrication, a screw jack with a trapezoidal screw has an overall efficiency of approximately 25% to 50%, and that this low efficiency is the basis for conditional self-locking, so loads can be held in position without an extra brake. The ball screw drive alone can reach about 98% efficiency, and a complete ball-screw jack including its worm gearbox is around 80% to 90%; it is not self-locking, so a motor brake or holding brake is required. [1]

Design World's Linear Motion Tips describes machine (acme) screw jacks as used for heavy loads in low-duty-cycle, low-speed applications and able, in some cases, to resist back-driving without power or a brake, while ball screw jacks are chosen where higher speeds and duty cycles are needed. [3]

Editorial note: self-locking of a trapezoidal screw is conditional; vibration or a steep lead can let it creep, so for a load that must never drop, ask for a brake or a safety nut whichever screw is used.

Give the supplier the load and its centre of gravity, stroke, lifting speed, cycles per hour and hours per day, required positioning accuracy and repeatability, whether the load must be held without power, number of lifting points and how they are synchronised, guide arrangement, mounting orientation, environment (washdown, chemicals, temperature, hazardous area) and the motor supply.

Size the load, duty cycle and drive power

ZIMM notes that the higher efficiency of ball screws turns less energy into heat, so the gearbox runs cooler and allows higher lifting speeds and, with suitable design, continuous operation up to 100% duty (ED); it recommends trapezoidal-screw jacks where self-locking, simpler peripherals and lower cost matter and the duty cycle stays low, such as occasional adjustment, clamping or positioning. [1]

Power Jacks lists standard screw jack capacities from 5 kN to 2,000 kN, with custom designs up to 3,500 kN, and says a machine screw jack suits low-duty applications while ball screw or roller screw jacks serve higher duties. Its imperial range covers 0.25 to 250 ton with machine screws for intermittent duty or ball screws for higher duty cycles. [2]

Editorial calculation: lifting 2,000 kg at 10 mm/s needs 2,000 × 9.81 × 0.010 ≈ 196 W at the load; at 30% overall efficiency (trapezoidal) the drive must supply about 196 / 0.30 ≈ 650 W, and at 85% (ball screw) about 196 / 0.85 ≈ 230 W, before guide friction and acceleration. [1] The load and speed are assumptions for the example.

Screw type, lead, self-locking or brake and duty ratings to request for a complete lift

The companies linked to this product sell lifting and rigging equipment and forklifts. Ask any supplier for the screw type and lead, efficiency, self-locking or brake arrangement, permitted duty cycle, and the load and stroke ratings of the complete lift.

Lifting screw, jack gearbox, motor and holding brake, guide columns and height sensor

Component	Role	Fix in the order
Lifting screw (trapezoidal, ball or roller)	Converts rotation to lift. [1] [2]	Type, diameter, lead.
Nut or screw jack gearbox	Carries the load; worm gearbox in jacks. [1]	Ratio and rating.
Drive motor and brake	Provides torque; brake holds ball screws. [1]	Power, brake, encoder.
Guide columns or rails	Take side loads off the screw.	Guide type and length.
Load platform or carriage	Carries the drum, tool or mould.	Size and capacity.
Position sensor and limits	Set height and stop over-travel.	Sensor type and accuracy.

Lift speed, stroke, load rating and motor power for a screw jack lift

Motor power follows from screw efficiency: ZIMM's example needs about 650 W with a trapezoidal screw against 230 W with a ball screw for the same lift. [1]

Field	What it means and published values	Ask the supplier for
Lifting Speed (mm/s)	Ball screws allow higher speeds. [1]	Speed at full load.
Lifting Height (mm)	Stroke of the screw.	Stroke and closed height.
Positioning Accuracy (mm)	Depends on screw, encoder and guides.	Accuracy and repeatability.
Motor Power (kW)	Example: about 650 W vs 230 W for the same lift by efficiency. [1]	Motor rating and gear ratio.
Load Capacity (kg)	Standard jacks 5–2,000 kN on one range. [2]	Static and dynamic rating.
Operating Pressure (MPa)	Not applicable to screw drives.	Confirm none.
Operating Temperature (°C)	Heat from low efficiency limits duty. [1]	Ambient and gearbox limits.
Ingress Protection	Motor and bellows protection.	IP rating; screw covers.
Supply Voltage (V AC)	Motor supply.	Voltage and frequency.
Frame Material (SS)	Stainless for chemical areas.	Frame and screw materials.
Guide Rail Type	Columns, profile rails or bushings.	Guide type.
Noise Level (dB(A))	Gearbox and screw noise.	Sound level.
Footprint (mm)	Space inside the machine.	Dimensions.

Send the load, stroke and duty together

Paste it into your enquiry below or into an email to a maker, then replace every bracket.

Load: [mass; centre of gravity; side loads]
Motion: [stroke; speed; accuracy]
Duty: [cycles per hour; hours per day]
Holding: [self-locking or brake; safety nut]
Screw: [trapezoidal; ball; roller; lifting points]
Environment: [chemicals; washdown; temperature; hazardous area]
Drive: [motor supply; control; position sensor]

See manufacturer records Send an enquiry through CNFX

Buyer questions

Is a trapezoidal or ball screw better for a lift?

ZIMM gives 25–50% efficiency and conditional self-locking for trapezoidal-screw jacks, against 80–90% and a required brake for ball-screw jacks. [1]

Which screw suits frequent lifting?

Ball screw jacks serve higher speeds and duty cycles; ZIMM says they can run up to 100% duty with suitable design. [1] [3]

How much load can screw jacks lift?

Power Jacks lists standard capacities from 5 kN to 2,000 kN and custom designs up to 3,500 kN. [2]

Sources and what still needs a direct check

Sources checked 2026-10-12. ZIMM and Power Jacks are screw jack makers explaining their products; Linear Motion Tips (Design World) is a trade publication. Efficiency and capacity values are as published.

ZIMM — What is the efficiency of screw jacks? ↗ Maker technical note Return to text ↑
Power Jacks — Screw jacks product range ↗ Maker product page Return to text ↑
Linear Motion Tips (Design World) — What's the difference between ball screw jacks and machine screw jacks? ↗ Trade publication Return to text ↑

Still to check yourself

Decide self-locking or brake for holding.
Check duty cycle against screw type.
Calculate drive power from load, speed and efficiency.
Specify guides to take side loads.
Verify the legal supplier and factory.