In large construction and fabrication spaces, overhead/bridge cranes do the heavy lifting—literally. This practical guide follows the journey from bare runways to a commissioned crane ready for service. We’ll cover preparation and surveys—with the same checklists pro installers use.
Overhead Crane, Defined
At heart, a bridge crane is a bridge beam that spans between two runway beams, carrying a trolley-mounted hoist for precise, vertical picks. The result is smooth X-Y-Z motion: cross-travel along the bridge.
They’re the backbone of heavy shops and assembly lines, from beam handling to turbine assembly.
Why they matter:
Safe handling of very heavy, unwieldy loads.
Less manual handling, fewer delays.
Lower risk during rigging, lifting, and transport inside facilities.
High throughput with fewer ground obstructions.
What This Install Includes
Runways & rails: continuous beams and rail caps.
End trucks: wheel assemblies that ride the rail.
Bridge girder(s): cambered and pre-wired.
Trolley & hoist: reeving, hook block, upper limit switches.
Electrics & controls: power supply, festoon or conductor bars.
Stops, bumpers & safety: overload protection, e-stops.
Based on design loads and bay geometry, the crane might be a single-girder 10-ton unit or a massive double-girder 100-ton system. The installation flow stays similar, but the scale, lift plans, and checks grow with the tonnage.
Make-Ready & Surveys
Good installs start on paper. Key steps:
Drawings & submittals: Freeze the GA and verify reactions with the structural team.
Permits/JSAs: Job Safety Analysis (JSA) for each lift step.
Runway verification: Check baseplates, grout pads, and anchor torque.
Power readiness: Confirm conductor bars or festoon supports, cable trays, and isolation points.
Staging & laydown: Lay out slings, shackles, spreader bars, and chokers per rigging plan.
People & roles: Brief everyone on radio calls and stop-work authority.
Tiny survey errors balloon into hours of rework. Spend time here.
Getting the Path Right
Runway alignment is the foundation. Targets and checks:
Straightness & elevation: shim packs under clips to meet tolerance.
Gauge (span) & squareness: Check centerlines at intervals; confirm end squareness and expansion joints.
End stops & buffers: Install and torque per spec.
Conductor system: Keep dropper spacing uniform; ensure collector shoe reach.
Record as-built readings. Misalignment shows up as crab angle and hot gearboxes—don’t accept it.
Girder Erection & End Trucks
Rigging plan: Choose spreader bars to keep slings clear of electricals. Taglines for swing control.
Sequence:
Install end trucks at staging height to simplify bridge pick.
Rig the bridge girder(s) and make the main smart construction lift.
Land the bridge on the end trucks and pin/bolt per GA.
Verify camber and bridge square.
Before anyone celebrates, bump-test long-travel motors with temporary power (under permit): ensure correct rotation and brake release. Lock out after test.
Cross-Travel Setup
Trolley installation: Hoist/trolley arrives pre-assembled or as modules.
Hoist reeving: Check rope path, sheave guards, and equalizer sheaves.
Limits & load devices: Set upper/lower limit switches.
Cross-travel adjustment: Align trolley rails on a double-girder.
Pendant/remote: Install pendant festoon or pair radio receiver; function-test deadman and two-step speed controls.
Grinding noises mean something’s off—stop and inspect. Don’t mask issues with higher VFD ramps.
Electrics & Controls
Power supply: Drop leads tagged and strain-relieved.
Drive setup: Enable S-curve profiles for precise positioning.
Interlocks & safety: Zone limits near doors or mezzanines.
Cable management: Keep loops short, add drip loops where needed.
Commissioning crews love clean labeling and clear folders. If it isn’t documented, it didn’t happen—put it in the databook.
ITP, Checklists, and Sign-Off
Inspection Test Plan (ITP): Third-party witness for critical steps.
Torque logs: Re-check after 24 hours if required.
Level & gauge reports: Attach survey prints.
Motor rotation & phasing: Confirm brake lift timing.
Functional tests: Anti-collisions and zone interlocks.
QA/QC is not paperwork—it’s your warranty in a binder.
Proving the System
Static load test: Apply test weights at the hook (usually 100–125% of rated capacity per spec).
Dynamic load test: Check sway, braking distances, and VFD fault logs.
Operational checks: Emergency stop shuts down all motions.
Training & handover: Maintenance intervals for rope, brakes, and gearboxes.
When the logbook is clean, the crane is officially in service.
Everyday Heavy Lifting
Construction & steel erection: handling long members safely.
Oil & gas & power: moving heavy pumps, skids, and pipe spools.
Steel mills & foundries: large part transfer.
Warehousing & logistics: high throughput lanes.
Once teams learn the motions, cycle times drop and safety improves.
Controls that Matter
Rigging discipline: dedicated signaler and stop-work authority.
Lockout/Tagout: test before touch every time.
Fall protection & edges: approved anchor points, guardrails on platforms, toe boards.
Runway integrity: regular runway inspection plan.
Duty class selection: match crane class to cycles and loads.
A perfect lift is the one nobody notices because nothing went wrong.
Troubleshooting & Pro Tips
Crab angle/drift: verify end-truck wheel diameters and gearbox mounts.
Hot gearboxes: misalignment or over-tight brakes.
Rope drum spooling: dress rope and reset lower limit.
Pendant lag or dropout: antenna placement for radio; inspect festoon collectors.
Wheel wear & rail pitting: lubrication and alignment issues.
A 10-minute weekly check saves days of downtime later.
Fast Facts
Overhead vs. gantry? Bridge cranes ride fixed runways; gantries walk on the floor.
Single vs. double girder? Singles are lighter and cheaper; doubles carry heavier loads and give more hook height.
How long does install take? Scope, bay readiness, and tonnage rule the schedule.
What’s the duty class? FEM/ISO or CMAA classes define cycles and service—don’t guess; size it right.
Who Gets the Most Value
Students and pros alike get a front-row seat to precision rigging, structural alignment, and commissioning. You’ll gain a checklist mindset that keeps cranes safe and productive.
Looking for a clean handover databook index you can reuse on every project?
Get the toolkit now so your next crane goes in cleaner, faster, and right the first time. Bookmark this guide and share it with your crew.
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