In large construction and fabrication spaces, overhead/bridge cranes do the heavy lifting—literally. This field-tested breakdown shows how a full overhead crane system comes to life inside a structural building. You’ll see hoist and trolley setup—with the same checklists pro installers use.
Bridge Crane Basics
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: cross-travel along the bridge.
They’re the backbone of heavy shops and assembly lines, from beam handling to turbine assembly.
Why they matter:
Controlled moves for large, expensive equipment.
Huge efficiency gains.
Repeatable, precise positioning that reduces damage.
Support for pipelines, structural steel, and big machinery installs.
System Components We’re Installing
Runways & rails: continuous beams and rail caps.
End trucks: wheel assemblies that ride the rail.
Bridge girder(s): single- or double-girder configuration.
Trolley & hoist: cross-travel carriage with lifting unit.
Electrics & controls: power supply, festoon or conductor bars.
Stops, bumpers & safety: overload protection, e-stops.
Depending on capacity and span, the crane might be a single-girder 10-ton unit or a massive double-girder 100-ton system. The installation flow stays similar, with heavier rigs demanding extra controls and sign-offs.
Pre-Install Prep
Good installs start on paper. Key steps:
Drawings & submittals: Freeze the GA and verify reactions with the structural team.
Permits/JSAs: Permit-to-work, hot work, working at height, rigging plans.
Runway verification: Survey columns and runway beams for straightness, elevation, and span.
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.
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: Check centerlines at intervals; confirm end squareness and expansion joints.
End stops & buffers: Install and torque per spec.
Conductor system: Mount conductor bars or festoon track parallel to the rail.
Log final numbers on the ITP sheet. Misalignment shows up as crab angle and hot gearboxes—don’t accept it.
Putting the Span in the Air
Rigging plan: Softeners protect painted flanges. Taglines for swing control.
Sequence:
Install end trucks at staging height to simplify bridge pick.
For double-girder cranes, lift both girders with a matched raise.
Use drift pins to align flange holes; torque to spec.
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: Mount wheels, align wheel flanges, set side-clearances.
Hoist reeving: Lubricate wire rope; verify dead-end terminations.
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.
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: Program VFDs for soft starts, decel ramps, and brake timing.
Interlocks & safety: E-stops, limit switches, anti-collision (if multiple cranes), horn, beacon.
Cable management: Secure junction boxes; label everything for maintenance.
Commissioning crews love clean labeling and clear folders. Photos of terminations help later troubleshooting.
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: Attach new house construction survey prints.
Motor rotation & phasing: Document bump tests.
Functional tests: Jog commands, inching speeds, limits, overloads, pendant/remote range.
A tidy databook speeds client acceptance.
Load Testing & Commissioning
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.
Only after these pass do you hand over the keys.
Applications & Use Cases
Construction & steel erection: handling long members safely.
Oil & gas & power: moving heavy pumps, skids, and pipe spools.
Steel mills & foundries: hot metal handling (with the right duty class).
Warehousing & logistics: high throughput lanes.
Floor stays clear, production keeps flowing, and precision goes up.
Safety & Engineering Considerations
Rigging discipline: dedicated signaler and stop-work authority.
Lockout/Tagout: clear isolation points for electrical work.
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: re-check runway gauge and wheel alignment.
Hot gearboxes: adjust brake air gap and reduce VFD decel.
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.
Little noises are messages—listen early.
FAQ Snippets
Overhead vs. gantry? Bridge cranes ride fixed runways; gantries walk on the floor.
Single vs. double girder? Span and duty class usually decide.
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.
What You’ll Take Away
If you’re a civil or mechanical engineer, construction manager, shop supervisor, or just a mega-project fan, this deep dive makes the whole process tangible. You’ll gain a checklist mindset that keeps cranes safe and productive.
Want ready-to-use checklists for runway surveys, torque logs, and load-test plans?
Download your pro bundle and cut hours from setup while boosting safety and QA/QC. Save it to your site tablet for quick reference.
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