The problem: mobile cranes between three bays
The customer was building a new fabrication hall with three connected work areas — cutting, welding and painting. Plates arrived at one end, finished members left at the other, and the old method was a hired mobile crane moving between bays.
That approach had two costs. It was slow, because every lift waited for the mobile crane to be repositioned and rigged. And it was unsafe: loads crossed areas where people were working, with no fixed lift path and no controlled travel.
What we specified
A single 16 t double girder crane would have been cheaper, but it could not serve all three bays without the hook losing coverage at the far ends. Two cranes, each on its own runway, gave full coverage and let the two ends of the process work independently.
The duty required VFD control on all motions. Fabrication shops start and stop constantly, and stepless control removes the load swing that makes long plates difficult to land accurately. We specified cabin control for long shifts, with radio remote as a second operating position for the painting bay.
The customer's supply is 415 V / 50 Hz, not the 380 V more common in China. The panel, motors and drives were built for 415 V, and the site voltage was confirmed in writing before production.
What was delivered
- 2 × 16 t double girder overhead cranes, 22.5 m span, 10 m lift
- Cabin and radio remote control, with changeover
- Rail clamps and rail fixings
- Spare parts pack: brake linings, limit switches, contactors
- Wheel load data and a runway/rail foundation drawing for the local steel contractor
- No-load and 125% load test video sent before shipment
The runway and building structure were outside our scope. We supplied the wheel loads and rail tolerances so the customer's local steel contractor could design and build the runway to match the crane, rather than the crane being adapted to a runway after the fact.
Installation and commissioning
The cranes were shipped in knock-down form. Our technician attended site for seven days to supervise erection, rail alignment, electrical connection and load testing, working with the customer's own installation crew.
That arrangement keeps the cost of installation local while making sure the critical steps — rail gauge, diagonal alignment, end stops and limit switch positions — are checked by someone who builds these machines every week.
Result
The plant now moves material with two fixed cranes instead of a hired mobile crane. Handling between bays no longer depends on equipment availability, and loads travel on a defined path above the work areas rather than through them.
Contract to shipment: 45 days. Site installation and commissioning: 7 days.