Gearbox

Gearbox Replacement.

Hoist, luffing and slewing gearboxes removed and replaced on board: rigging, drum removal, alignment, oil fill and load test.

Service line 08Hydraulic · Mechanical · ElectricalReport included

Opened winch frame with the drum lifted and the gearbox seat exposed — Gearbox seat

01What we do

A hoist or luffing gearbox that has failed rarely gives a second warning.

A hoist or luffing gearbox that has failed rarely gives a second warning. Metal on the magnetic plug, a rising noise under load or a brake that no longer holds are the usual signs, and once the teeth or bearings have gone the safe answer is to take the gearbox out and fit a new or overhauled unit.

On most deck cranes the gearbox sits inside or beside the winch drum, in a crane house with little headroom. Our team rigs chain blocks from the crane structure, unreeves the wire, lifts the drum out of its frame and then draws the gearbox, so the work is done on board without taking the crane ashore.

The replacement unit is checked against the old one for ratio, flange and spline before it goes in. After fitting we align the drive, fill and vent the oil, reeve the wire, set the brake and run the winch under load before the crane goes back into service.

Winch drum with wire lifted out of its frame during a gearbox change — Drum removed08

What to send us

Gearbox type plate: maker, model, ratio and serial number
Crane make and model, and which winch: hoist, luffing or slewing
Photos of the winch, the drum and the space around it in the crane house
Port, dates and how long the crane can be out of service

Describe the job

02Scope

What the service covers.

The work items under this service line, as listed by our engineers.

01
Fault AssessmentOil sample and magnetic plug check, noise and play under load, and the decision between repair in place and full replacement.
02
Replacement Unit SourcingNew gearbox from the maker or an overhauled exchange unit, matched on ratio, mounting flange, input spline and brake interface.
03
Rigging / Lifting on BoardChain blocks and lifting points set up inside the crane house, with the lift plan agreed with the vessel before work starts.
04
Wire and Drum RemovalHoist or luffing wire unreeved and secured, drum lifted out of its frame to reach the gearbox.
05
Gearbox Change-outOld unit drawn out, seat and flange faces cleaned and inspected, new unit fitted and bolted to the specified torque.
06
Alignment / Brake SettingMotor, gearbox and drum alignment checked, multi-disc brake set and release pressure verified.
07
Oil Fill / Run-inCorrect oil grade and level, breather and seals checked, run-in without load and then under load.
08
Load Test / ReportFunctional and load test with water bags or test weights where required, followed by a written service report.

On the job

Photos from recent attendances.

Technician rigging a winch drum with chain blocks inside a crane house — Drum lift · onboard01

Winch drum with wire and yellow lifting straps set down on a protected deck — Drum on deck04

Multi-stage planetary gearbox, freshly painted, on the workshop floor — Planetary gearbox05

Yellow multi-stage planetary gearbox on a pallet in the workshop — Planetary gearbox06

03Typical jobs

Faults we are called for.

01Hoist gearbox noisy with metal on the plug: drum removed on board, exchange gearbox fitted, crane back in service after the load test.
02Luffing gearbox leaking from a cracked housing: replacement unit sourced to the same flange and ratio, fitted and run in.
03Slewing gearbox with worn pinion and play in the bearings: gearbox and pinion changed together, backlash with the ring gear set.

04Questions

Asked before the first visit.

Can a gearbox be replaced without taking the crane ashore?

In most cases, yes. The drum and gearbox are lifted inside the crane house with chain blocks rigged from the structure. Where headroom or access does not allow it, we plan the lift with the crane jib or a shore crane.

New or overhauled gearbox?

Both. A new unit from the maker is the first choice when it can arrive in time. When lead time matters, we offer an overhauled exchange unit or a compatible gearbox with the same ratio and interfaces.

How long is the crane out of service?

It depends on the crane and the access, and we give a time estimate once we have seen the photos or attended. Having the replacement unit on board before the crane is opened keeps the downtime short.

Spare parts / equipment