Anand Gears supplies machine screw jacks from 5 kN to 350 kN with either a trapezoidal (Tr) lifting screw or a ball screw. The worm gearbox on top looks similar; the linear element decides efficiency, heat, and whether the load stays put when power dies. This is a buyer-facing comparison — no brand theatre.
Trapezoidal (Tr) screw jacks
A trapezoidal thread works like a power screw: sliding contact between steel screw and bronze nut. Typical industrial efficiency is on the order of 35–45% (product literature). That sliding friction is exactly why properly pitched Tr screws with suitable worm ratios are often self-locking — the load does not unwind when the motor stops.
Where Tr wins
- Infrequent lifts and long hold periods (press tables, platforms, gates, mould height)
- Safety preference for mechanical hold without relying on a brake
- Cost-sensitive capacity in the same kN class
- Simpler field maintenance — grease, inspect nut backlash, replace bellows
- Intermittent duty that matches classic worm jack thermal limits
Trade-offs — more input power for a given lift speed; more heat under high cycle rates; nut wear is the planned life limiter (monitor with a safety nut).
Ball screw jacks
Ball screws roll recirculating balls between screw and nut. Efficiency can reach about 90% on the same product material — much less friction, less heat for a given speed, smaller motor for frequent cycling.
Where ball wins
- High duty cycle and frequent positioning
- Faster lift rates without overheating the worm mesh
- Lower input power for the same linear work
- Precision-oriented moves where smooth response matters
Trade-offs — ball screws need a brake (or other hold) when power is off; they cost more in the same capacity class; contamination control (bellows, seals) matters more because ball tracks hate grit.
Side-by-side
| Topic | Trapezoidal (Tr) | Ball screw |
|---|---|---|
| Efficiency (order of magnitude) | ~35–45% | up to ~90% |
| Self-locking hold | Often yes (check pitch/ratio) | No — use brake |
| Duty cycle | Intermittent preferred | High cycling preferred |
| Motor size | Larger for same speed | Smaller for same speed |
| Contamination | Tolerant with good grease | Sensitive — protect tracks |
| Typical buyer priority | Hold + economy | Speed + duty |
Decision shortcuts
- Must hold without power, few moves per hour → Tr trapezoidal.
- Many cycles per hour, motor size tight → ball screw + brake.
- Unsure → state duty cycle and hold requirement on the RFQ; we will not force a ball screw where self-locking is the real need.
Both types are available across the catalogue capacity band in TP/TPR configurations — see machine screw jacks and sizing notes in how to size a screw jack.
Related: Screw Jack vs Hydraulic · Maintenance & Lubrication · Contact