We repair and load test offshore cranes and A-frames on OSVs, survey and diving vessels, work barges, accommodation barges and fixed installations operating from the UAE. Most of this work is in Abu Dhabi, at the Mussafah bases and in yards, with offshore attendance when a unit cannot come in.
The equipment
Offshore and vessel cranes: knuckle-boom, telescopic and lattice-boom cranes, typically electro-hydraulic or diesel-hydraulic. Their hydraulics include luffing and folding (knuckle) cylinders, telescopic cylinders, slewing motors and gearboxes, main and auxiliary hoist winches with their motors and brakes, and a control valve block with load-holding valves. Larger cranes may have motion or heave compensation systems.
A-frames and stern frames on survey, diving, cable and anchor handling vessels: two large luffing cylinders tilt the frame outboard and inboard, often with a winch and sometimes a snubber or docking head. Cylinder synchronisation and load-holding are critical.
Barge cranes on accommodation and work barges, often older cranes worked hard on long projects.
The power usually comes from a dedicated hydraulic power unit, either in the crane pedestal or in a deck or engine room space.
Typical faults
- Luffing cylinder drift, from worn piston seals or leaking load-holding valves. A boom or A-frame that creeps under load must be stopped and investigated. See cylinder drift causes.
- Pitted and corroded rods on cylinders exposed to spray and sun. Pitted rods destroy new seals, so they need re-chroming by our machining partners or new rods.
- Uneven A-frame movement from internal leakage in one of the paired cylinders or a valve fault.
- Slow hoisting or slewing, from worn pumps or motors, or relief valves out of setting.
- Slewing ring and gearbox problems, noisy or with backlash, often found during inspection.
- Overheating of HPUs in hot deck spaces and engine rooms. See hydraulic overheating in UAE heat.
- Hose failures from UV, abrasion and age, which are both a safety and a pollution risk.
- Accumulator pre-charge loss in crane and A-frame emergency systems. See accumulator safety and pre-charge.
- SLI and limit faults, which stop the crane or let it be overloaded.
Standards and inspection pressure
Offshore cranes are designed and certified to offshore crane standards (for example API Spec 2C or EN 13852), and to class rules where the crane is classed. In service, they are examined periodically and load tested after installation, after major repairs and at intervals set by class, flag and the operator. Charterers and offshore vessel inspection schemes check the crane’s certificates, load test records and maintenance history before and during a charter.
For proof loads, the class and ILO table is common for ship cranes:
| SWL | Proof load |
|---|---|
| Up to 20 t | SWL + 25% |
| 20 to 50 t | SWL + 5 t |
| Over 50 t | SWL + 10% |
Offshore cranes may have different test requirements under their design standard and class; we confirm the right load with you and the surveyor. Use our proof load calculator for a first check.
What we do
Troubleshooting. With pressure gauges at the HPU, valves and actuators, we find whether the problem is the pump, valves, cylinder, motor or controls before removing parts.
Cylinder overhaul. Luffing, folding, telescopic and A-frame cylinders are taken to our Sharjah workshop, stripped, measured, resealed or repaired, and pressure tested on the bench at 1.5 times working pressure with a report. A reseal typically takes 3 to 7 working days after strip-down, longer if a rod needs re-chroming. See hydraulic cylinder repair.
Motors and pumps. Slewing motors, hoist motors and HPU pumps are overhauled and tested. See pumps and motors.
Valves. Load-holding, counterbalance and control valves are overhauled and bench tested. See valves and VRCS.
HPUs and accumulators. Overhaul, accumulator pre-charge checks and bladder replacement. See hydraulic power units.
Wire rope supply and renewal with certificates.
Re-hosing of the crane or A-frame as a planned job. See hose management.
Load tests with water bags and calibrated load cells up to 150 t, with LMI/SLI calibration checks and a full report. Our tests are regularly witnessed by class surveyors from DNV, Bureau Veritas, Lloyd’s Register and ABS. See load testing.
Complex motion and heave compensation control systems may need the crane maker’s software or support; we work with your team and the maker where that applies.
What to send for a quote
- Vessel or unit name, location and when it is available.
- Crane or A-frame maker, model and SWL, with nameplate photographs.
- The fault, any alarms, and photographs of leaks and rod surfaces.
- Cylinder data: bore, rod and stroke if known.
- For load tests: the last certificate, class society, and the charter or audit deadline.
We usually quote within one working day of receiving photos and nameplate data. We focus on overhauls, load tests and planned work rather than single-hose call-outs.
