MAXPULL GM-3 / PL-680001 Manual Hand Winch

MAXPULL GM-3 / PL-680001 Manual Hand Winch – 300 kg (660 lb) Capacity

The MAXPULL GM-3 (referenced under OEM/assembly code PL-680001) is a 360-degree rotating manual spur-gear hand winch manufactured in Japan by MAXPULL Machinery & Engineering Co., Ltd.. Engineered for vertical hoisting and horizontal traction up to 300 kg (660 lbs) at the 5th rope layer, this unit utilizes a precision-stamped, double-ribbed carbon steel housing paired with heat-treated profile-shifted spur gears and sealed ball bearings throughout.

The GM-3 is a purely mechanical torque-multiplier assembly with zero electrical terminals or hydraulic ports. Mechanical energy is transmitted via a 250 mm (9.84 in) adjustable crank lever directly into a 6.25:1 reduction gear train, delivering controlled line pull with a low handle effort of 13.3 kgf (29.3 lbs) at full rated load.

Model Details

• Primary Model Number: GM-3 (Standard Steel Series, 360° Full-Rotation Handle)
• Manufacturer Part Number (MPN): GM-3 / PL-680001
• Country of Manufacture: Japan (Chiba Factory)
• Series Architecture: GM Series (Rotating Crank) vs. MR Series (Ratchet Crank for restricted arc spaces)
• Drive & Braking Type: Spur Gear Reduction with Automatic Fail-Safe Mechanical Friction Brake

Features

1. Fail-Safe Mechanical Friction Brake: Automatically engages the moment cranking stops, holding suspended loads securely without back-driving, even if external impact strikes the stopper arm.
2. Profile-Shifted Heat-Treated Spur Gears: Custom-machined and heat-treated gear teeth maximize mechanical transmission efficiency while resisting pitting and tooth shear under continuous duty cycles.
3. Double-Safety Wire Rope Locking System: Combines a specialized multi-wrap retention drum groove with a bolted mechanical rope-anchoring clamp plate to prevent cable pull-out under peak tension.
4. Full-Ball-Bearing Drivetrain: Equipped exclusively with industrial-grade shielded ball bearings on all rotational shafts to minimize friction losses and reduce operator handle fatigue.
5. Modular Bolt-Together Press-Steel Frame: Constructed from ribbed, double-plate pressed steel bolted together rather than welded, allowing rapid field disassembly and component-level overhaul.

Compatible Equipment & Wire Rope Assemblies

• Wire Rope Compatibility: Ø 6 mm (1/4 in) galvanized or AISI 316 stainless steel aircraft cable in 6×37 or 6×36 flexible strand configurations. (Note: 7×19 or 6×19 stiffer constructions are not recommended due to the 60.5 mm drum barrel bending radius).
• Compatible Davits & Cranes: Light-duty marine rescue/utility davits, jib cranes, engine room overhead lifting beams, and gangway/accommodation ladder handling frames.
• Optional MAXPULL Configurations & Variants:
  • GM-3-SI: Built-in stopper arm guard version (prevents accidental brake release in public or tight deck areas).
  • GM-3-GS-SI: Hot-dip galvanized frame with 304 stainless steel fasteners for direct salt-spray exposure.
  • GM-3-SIC: Dust- and water-sealed brake housing for washdown and offshore environments.
  • GM-3-LUSI: Reverse-wound counter-clockwise lifting configuration.

Part Number Cross-References

• MAXPULL OEM Codes: GM-3, GM3, GM-3-SI, PL-680001
• Galvanized Equivalent: GM-3-GS-SI (Cross-Ref: Grainger / Raptor 436R18 / CT2KPG)
• Ratchet Handle Equivalent (Same Gear Train): MAXPULL MR-3 / MR-3-SI
• 304 Stainless Steel Equivalent: MAXPULL ESB-3 / ESB-3-SI

Frequently Asked Questions

What is the maximum lifting capacity of the MAXPULL GM-3 hand winch?

The MAXPULL GM-3 has a Safe Working Load (SWL) of 300 kg (660 lbs) measured at the 5th layer of 6 mm wire rope. When spooled to the 6th (outermost) layer, the rated capacity derates to approximately 268 kg (590 lbs) due to the larger effective drum radius.

Does the MAXPULL GM-3 hold a suspended load automatically when I let go of the handle?

Yes. The GM-3 is equipped with an automatic, load-actuated mechanical friction brake. Turning the crank clockwise lifts the load; releasing the handle immediately locks the load in place, and turning counter-clockwise provides controlled lowering.

What wire rope size and length fit the MAXPULL GM-3 drum?

The drum is engineered for Ø 6 mm (1/4 inch) flexible wire rope (6×37 or 6×36 construction). The drum holds a maximum of 32 meters (104 feet) across 6 layers.

Can the MAXPULL GM-3 be mounted vertically on a bulkhead or wall?

Yes. Because the GM-3 utilizes a closed spur-gear drive and a dry mechanical load brake, it operates reliably in any 360-degree mounting orientation, including horizontal deck plates, vertical bulkheads, and overhead davit frames, provided there is 250 mm of radial clearance for full crank rotation.

Is the MAXPULL GM-3 certified for lifting personnel?

No. Like all standard industrial material-handling winches, the MAXPULL GM-3 is strictly rated for lifting and pulling cargo and equipment. It must never be used for man-riding or personnel suspension.