Cranes & Material Handling
The structure outlivesits controls by decades
The same argument as a machine tool, on a bigger scale. The steel is good for another thirty years; the contactors, resistors and pendant are not. We renew the electrics and leave the structure in service.
EOT Cranes
Long travel, cross travel and hoist motions re-controlled on VFDs.
Electric overhead travelling cranes running on contactor-and-resistor stepping start hard, stop hard and swing the load doing it. Putting all three motions on variable frequency drives gives a ramp instead of a step, which is easier on the gearbox, easier on the structure and a great deal easier on the operator trying to place a load.
- Long travel, cross travel and hoist on variable frequency drives
- Contactor-and-resistor stepping replaced with controlled ramps
- Conductor bar or festoon power supply renewed as required
- Existing structure, girders and gearboxes kept in service
Double Girder Cranes
Heavier duty, longer spans, and two hoists that have to agree.
Longer spans and heavier duty bring problems a single girder crane does not have: skew on long travel, and two hoists that have to lift as one when a load is slung between them. Both are control problems before they are mechanical ones.
- Synchronised motion where two hoists lift one load
- Anti-sway on long and cross travel
- Load monitoring and overload protection that trips at its setting
- Skew detection and correction on long spans
Monorail & Hoists
Underslung, monorail and single girder handling, and the hoists on them.
Bay and workshop handling — underslung and monorail runways, single girder cranes, and the wire rope or chain hoists working on them. Smaller equipment, but the same failures: brakes past adjustment, limit switches bypassed years ago, and overload protection nobody has proven since it was installed.
- Underslung, monorail and single girder runways
- Wire rope and chain hoists, including brake replacement
- Limit switches restored rather than bypassed
- Overload protection proven to trip at its setting
- Festoon or conductor bar power supply
Crane Retrofit & Automation
New electrics on a crane already in service, planned around your shutdown.
A crane retrofit is mostly a planning problem. The bay it serves cannot stop for a month, so the panel is built and tested off site and the work is cut to fit the shutdown you actually have. Safety systems go in as part of the control — limit switches, anti-collision, load cells and zone protection wired into the drives rather than bolted on beside them.
- Panel built and tested off site, fitted in your shutdown window
- Anti-collision and zone protection where cranes share a runway
- Load cells and load monitoring wired into the drives
- Safety circuit rebuilt to the duty rather than patched
- Handover with schematics, settings and a spares list
What a crane retrofit covers
- VFD drives on all motions
- Control and relay panel
- Festoon or conductor bar
- Limit switches
- Anti-collision
- Load cells & monitoring
- Anti-sway
- Radio remote control
- Brake replacement
- Cabin or pendant controls
Radio Remote Control
The operator standing where they can see the load, not under it.
A pendant ties the operator to the crane and often to a position where the load is between them and where it is going. Radio remote puts them where they can see. The part worth getting right is the handover between stations and what happens when the link drops — both are interlocked rather than assumed.
- Pendant replaced with radio remote, or both kept in parallel
- Interlocked handover between control stations
- Defined, tested behaviour when the radio link is lost
- Spare transmitter paired and ready rather than ordered later
Tell us what the machine is doing
Send the make and model, the control that is on it, or just what has stopped working. One of our engineers will come back to you.
Talk to our engineers