L-leg twin-hoist gantry crane

Structure and operating principle

An L-leg gantry frame carries two conventional electric hoists.

Two or more lifting units allow separate pick-up points along a long or complex load. Load sharing changes with the centre of gravity, lifting-point geometry and relative hook heights; simultaneous motion requires an approved control and lifting arrangement.

Application and selection

Suitable for engineered handling of long fabrications or large assemblies. Any turning, load transfer between hooks or combined lift is a separately planned operation, not an automatic capability of every multi-hoist machine.

Working method

1. Before work, authorised personnel confirm the load and its centre of gravity, the permitted machine configuration, the route and receiving position. Complete the checks specified for the equipment, verify protective functions by the approved method and stop if a defect affects safe operation.

2. A competent lift planner determines the force at each lifting point throughout the motion. Connect the approved rigging, take up load in a controlled sequence and verify sharing before travel. One designated person coordinates the operation and any stop signal is acted on immediately.

3. After the task, place the load on stable supports and leave the equipment in its prescribed safe state. Record faults and abnormal events. Maintenance or jam clearance requires secure isolation of relevant energy, including stored hydraulic, pneumatic and gravitational energy.

Precautions and maintenance

Do not add individual hoist ratings to obtain a combined capacity. Do not assume equal load sharing or automatic synchronisation. Confirm permitted trolley separation, hook paths, anti-collision functions and any approved rotation sequence.

Inspection frequency, wear/discard criteria, lubrication, brake adjustment and replacement parts follow the supplied instructions and applicable local requirements. Only competent personnel may maintain the equipment; return to service follows the prescribed checks.

Configuration and standards

This is an equipment-selection and operating-principle overview, not a complete operator manual, lift plan or certificate. Verify rated load, duty, geometry, environment and protective functions against the nameplate, approved drawings and delivered instructions. Do not combine separate series maxima into one promised configuration.

Requirements follow the destination and installation, not the website language. China: determine the applicable GB/T references and statutory equipment obligations. EAEU destinations: check the applicable TR CU/EAEU regulations, amendments and conformity documents. English-speaking markets: select the relevant national rules; US OSHA and UK HSE references are not universal law. EU projects require their own applicable conformity assessment.