When loads get too big for forklifts and too precise for rough handling, teams turn to overhead cranes. This practical guide follows the journey from bare runways to a commissioned crane ready for service. You’ll see hoist and trolley setup—with the same checklists pro installers use.
Overhead Crane, Defined
An overhead crane rides on parallel runways anchored to a building frame, carrying a trolley-mounted hoist for precise, vertical picks. The system delivers three axes of motion: long-travel along the runway.
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.
Repeatable, precise positioning that reduces damage.
High throughput with fewer ground obstructions.
Scope at a Glance
Runways & rails: continuous beams and rail caps.
End trucks: wheel assemblies that ride the rail.
Bridge girder(s): cambered and pre-wired.
Trolley & hoist: cross-travel carriage with lifting unit.
Electrics & controls: VFDs, radio remote, pendant.
Stops, bumpers & safety: overload protection, e-stops.
Based on design loads and bay geometry, you may be dealing with modest shop lifts or major industrial picks. The installation flow stays similar, but the scale, lift plans, and checks grow with the tonnage.
Before the First Bolt
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. Measure twice, lift once.
Rails & Runways
If rails are off, nothing else will run true. Targets and checks:
Straightness & elevation: shim packs under clips to meet tolerance.
Gauge (span) & squareness: Use feeler gauges on splice bars, torque rail clips.
End stops & buffers: Verify clearances for bumpers at both ends.
Conductor system: Mount conductor bars or festoon track parallel to the rail.
Record as-built readings. Misalignment shows up as crab angle and hot gearboxes—don’t accept it.
Lifting the Bridge
Rigging plan: Softeners protect painted flanges. Taglines for swing control.
Sequence:
Lift end trucks to runway level and set temporarily on blocks.
For double-girder cranes, lift both girders with a matched raise.
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): confirm limit switch wiring. Lock out after test.
Cross-Travel Setup
Trolley installation: Mount wheels, align wheel flanges, set side-clearances.
Hoist reeving: Check rope path, sheave guards, and equalizer sheaves.
Limits & load devices: Check overload/SLI and emergency stop.
Cross-travel adjustment: Verify end stops and bumpers.
Pendant/remote: Install pendant festoon or pair radio receiver; function-test deadman and two-step speed controls.
A smooth trolley with a quiet hoist is a sign of good alignment. Fix the mechanics first.
Drive Tuning & Interlocks
Power supply: Conductor bars with collectors or a festoon system.
Drive setup: Program VFDs for soft starts, decel ramps, and brake timing.
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.
Trust but Verify
Inspection Test Plan (ITP): Third-party witness for critical steps.
Torque logs: Re-check after 24 hours if required.
Level & gauge reports: Note any corrective shims.
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.
Ready for Work
Static load test: Apply test weights at the hook (usually 100–125% of rated capacity per spec).
Dynamic load test: Travel long-run, cross-travel, and hoist at rated speed with test load.
Operational checks: Emergency stop shuts down all motions.
Training & handover: Operator basics, daily pre-use checks, rigging do’s & don’ts.
When the logbook is clean, the crane is officially in service.
Where These Cranes Shine
Construction & steel erection: placing beams, trusses, and precast.
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: rated slings & shackles, correct angles, spreader bars for load geometry.
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.
Safety isn’t a jct contract stage—it's the whole show.
Keep It Rolling
Crab angle/drift: re-check runway gauge and wheel alignment.
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: add rail sweeps and check clip torque.
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? Anything from a couple weeks to a few months.
What’s the duty class? FEM/ISO or CMAA classes define cycles and service—don’t guess; size it right.
Why Watch/Read This
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.
Need a field bundle with JSA templates, rigging calculators, and commissioning sheets?
Grab the installer pack and cut hours from setup while boosting safety and QA/QC. Save it to your site tablet for quick reference.
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