Henan Mine Crane · Heavy-Duty Bridge Crane Systems
Double Girder Overhead Crane for Heavy-Duty Lifting
Top-running double girder bridge cranes configured for higher capacities, longer spans, demanding duty cycles, improved hook height and process-specific load handling.
Henan Mine Crane supplies electric-hoist, open-winch, double-trolley and special-purpose double girder overhead cranes. Each proposal coordinates the bridge, trolley, runway reactions, working class, controls, safety functions, electrical supply, documentation and site boundary.
STANDARD PRODUCT FAMILY
3–32 t or Engineered
STANDARD SPAN RANGE
Up to 31.5 m
STANDARD WORKING CLASS
A3–A6
CONFIGURATION BASIS
Load, Span, Duty & Process
What Is a Double Girder Overhead Crane?
A double girder overhead crane uses two parallel bridge girders carried by end trucks that travel along elevated runways. A trolley or electric hoist travels across the bridge, creating three powered motions: vertical lifting, cross travel and long travel. The same equipment family is also described as a double girder bridge crane, double girder EOT crane or double girder overhead travelling crane.
The two-girder structure provides a stable platform for higher loads, longer spans, demanding operating cycles and larger trolley mechanisms. A top-running trolley can move above or between the girders, which often improves the highest hook position compared with an underslung hoist arrangement. Walkways, maintenance platforms, operator cabins, service hoists and process equipment can also be integrated when the approved design requires them.
Double girder construction is not automatically required at every capacity. A single-girder crane can remain more economical where load, span, duty and headroom are moderate. Double girder selection becomes commercially justified when the required capacity, bridge stiffness, lifting height, trolley arrangement, service access or process function cannot be achieved efficiently with a lighter configuration.
The crane and its runway operate as one structural system. Bridge self-weight, trolley position, lifted load, acceleration, braking, skewing and impact generate vertical, lateral and longitudinal forces. Final wheel loads and support reactions must be coordinated with runway beams, columns, brackets and foundations before fabrication.
Double Girder Overhead Crane Configurations
01 · Electric-Hoist Double Girder Crane
A compact electric wire-rope hoist travels on a trolley arrangement supported by two girders. The configuration suits general industrial handling where moderate capacity, controlled cost and relatively simple maintenance have priority.
02 · Open-Winch Double Girder Crane
A purpose-designed trolley carries separate drum, motor, gearbox, brakes, sheaves and controls. This architecture supports higher capacity, longer lift, demanding duty, redundancy and process-specific reeving.
03 · Double-Trolley Overhead Crane
Two independently controlled trolleys provide separated lifting points for long loads, load turning, synchronized lifting or multiple production tasks. The control philosophy defines independent, coordinated and restricted operating modes.
04 · Low-Headroom Double Girder Crane
An optimized trolley and bridge arrangement maximizes upper hook elevation where roof clearance is limited. Girder depth, trolley envelope, walkway access and runway level require coordinated review.
05 · Process Double Girder Crane
Grab, magnet, clamp, rotating beam, C-hook, ladle beam or other attachments convert the crane into a process machine. Structure, mechanisms, controls and safety provisions are selected around the handled material.
06 · Automated Double Girder Crane
Position feedback, PLC control, anti-sway, collision management and plant interfaces support repeatable semi-automatic or unmanned cycles. Manual recovery and maintenance modes remain part of the control design.
A packaged electric hoist and an open-winch trolley are not interchangeable price alternatives. The open-winch platform is selected when reeving, braking, duty, redundancy, speed range, maintenance access or process risk exceeds the capability of a standard packaged hoist.
A project configuration should identify the trolley type, number of hooks, reeving, working class, motion speeds, control mode and service access before commercial comparison.
Selection Considerations
A reliable specification starts with the lifting process and building section, not with a catalogue model. The following inputs establish the technical and commercial basis for a double girder overhead crane proposal.
01 · Gross Suspended Load
Record maximum payload, normal payload, lifting beam, hook block, slings, clamps, magnets and every component carried below the trolley. Rated capacity follows the maximum approved suspended load.
02 · Span and Travel Coverage
State runway rail-center span, bay travel length, pickup and placement zones, side approach, end approach and any maintenance or transfer areas.
03 · Lift and Headroom
Define lowest pickup level, highest hook position, rail elevation, roof obstruction, load height, rigging depth and any extraction distance above machinery.
04 · Duty and Load Spectrum
Provide lifts per hour, shifts, annual operating hours, travel distances, average load and frequency of lifts near rated capacity. Working class follows actual service.
05 · Runway and Building
Confirm rail type, runway beams, column spacing, brackets, foundations, allowable reactions and existing structural information. Crane capacity alone cannot validate the runway.
06 · Motion and Positioning
Specify lifting, trolley and bridge speeds, low-speed range, stopping behavior, positioning tolerance, variable-frequency control and anti-sway requirements.
07 · Load Handling Function
Identify hook, grab, magnet, clamp, rotating beam, ladle beam or another attachment together with load dimensions, center of gravity and pickup method.
08 · Environment and Acceptance
Define temperature, dust, corrosion, hazardous classification, indoor or outdoor service, governing requirements, inspection authority and commissioning boundary.
Commercial control: rated capacity, span and lift are insufficient without working class, runway data, trolley architecture, attachment details and a written supply boundary.
Double Girder Compared with Other Overhead Crane Configurations
| Configuration | Structural Arrangement | Typical Duty | Capacity Position | Primary Decision Point |
|---|---|---|---|---|
| Double girder with electric hoist | Two bridge girders; packaged wire-rope hoist | General industrial loads requiring stronger bridge stiffness or improved hook height | Moderate to high within the approved hoist range | Hoist duty, trolley arrangement, wheel loads and maintenance clearance |
| Double girder with open-winch trolley | Two girders; purpose-designed trolley and reeving | Heavy loads, long lift, high duty and process handling | High to very high project-specific capacity | Reeving, brakes, redundancy, access, heat load and control architecture |
| Single girder overhead crane | One bridge girder; normally underslung hoist | Routine workshop, assembly, maintenance and warehouse handling | Light to moderate project range | Lower self-weight and cost when capacity, span, duty and headroom permit |
| Double-trolley overhead crane | Two trolley or hoist units on one bridge | Long loads, rotation, synchronized lifting and separated pick points | Project-specific combined and individual loads | Load sharing, synchronization, collision zones and allowable combined operation |
| Underhung double girder crane | Bridge suspended below multiple runway supports | Large clear-floor buildings, hangars and special assembly areas | Project-specific | Roof reactions, support alignment, load distribution and suspended connections |
| Double girder gantry crane | Two girders carried by legs running on ground rails | Outdoor yards or facilities without an elevated runway structure | Moderate to very high project range | Wind, rail foundations, skew control, storm protection and clear travel path |
Technical Specification Framework
The published general electric-hoist family provides a preliminary selection envelope. The approved technical proposal controls final values, and open-winch or special-purpose cranes are engineered beyond the standard family when required.
| Parameter | Preliminary Range or Option | Engineering Basis | Quotation Requirement |
|---|---|---|---|
| Rated capacity | 3–32 t for the published general electric-hoist family; engineered capacities available | Gross suspended load including all below-hook equipment | State main and auxiliary hook capacities separately |
| Span | Up to 31.5 m for the published general family | Runway rail centerline to centerline | Confirm actual building bay and end approaches |
| Lifting height | 3–10 m for the published general family; project-specific lifts available | Lowest pickup to highest required hook elevation | Include load and rigging depth |
| Working class | A3–A6 for the published general family | Load spectrum, starts, travel and annual service | Mechanism classes may differ from whole-crane class |
| Hoisting mechanism | Electric wire-rope hoist or engineered open-winch trolley | Capacity, duty, lift, speed, redundancy and environment | Define main, auxiliary and maintenance hooks |
| Control mode | Pendant, radio remote or operator cabin | Visibility, travel distance, process risk and site practice | Multiple modes require authority and transfer logic |
| Power supply | Three-phase 380 V, 50 Hz baseline; project supply coordinated separately | Country grid, voltage tolerance, frequency and earthing | Transformer or conversion scope stated in the quotation |
| Runway interface | Top-running rails and building-supported or freestanding runway | Wheel loads, rail, beam, columns, brackets and foundations | Runway scope and structural approval separated commercially |
Special cranes for molten metal, hazardous areas, magnetic loads, bulk handling or automated production require a dedicated parameter sheet. General product-family values must not be transferred to a process crane without review.
Hoisting, Travel and Control System
Mechanism architecture determines operating performance, maintenance workload and lifecycle risk. Every motion should be selected from the declared load spectrum and production cycle.
Hoist or Open-Winch Trolley
Packaged hoists control cost and simplify general service. Open-winch trolleys provide configurable drums, reeving, brakes, speeds and redundancy for heavy or high-duty operation.
Main and Auxiliary Hoists
An auxiliary hook supports faster handling of lighter loads, maintenance work and load orientation. Combined-load restrictions and hook separation must be documented.
Variable-Frequency Drives
Controlled acceleration, deceleration and low-speed operation reduce load swing and mechanical shock. Drive settings follow motor, brake, gearbox and process requirements.
Brakes and Holding Functions
Service and holding brakes are selected around load consequence, duty and applicable requirements. Monitoring or redundant arrangements are added where the process demands them.
Travel and Skew Control
Matched end-carriage drives, wheel geometry, rail alignment and optional feedback control support stable bridge travel. Mechanical alignment remains essential even with electronic correction.
Positioning and Anti-Sway
Encoders, laser positioning, zone control and anti-sway functions support repeatable placement. Required accuracy and fallback behavior must be defined before control design.
Operator Interface
Pendant, radio and cabin controls are selected around visibility, travel distance, heat, dust and process risk. Alarms, indicators and authorization levels form part of the interface.
Safety and Compliance
Overload protection, limits, emergency stop, buffers, end stops, travel warning and electrical protection form the base system. Additional functions follow the hazard assessment and governing standard.
Top-running multiple-girder cranes with top-running trolley hoists fall within the scope of ASME B30.2 where that standard governs the project. EN, ISO, FEM, national regulations or owner specifications may also apply. The contract should identify the governing edition, certification boundary, inspection authority and acceptance procedure.
Applications and Working Conditions
| Industry | Typical Load | Recommended Direction | Operating Objective | Critical Project Input |
|---|---|---|---|---|
| Heavy manufacturing and fabrication | Machines, weldments, dies, fixtures and large assemblies | Electric-hoist or open-winch double girder crane | Stable full-bay lifting and controlled positioning | Maximum load, assembly sequence, duty and hook approach |
| Steel mill and foundry | Ladles, slabs, coils, billets, rolls, scrap and maintenance equipment | Process double girder crane with dedicated attachment | High duty, heat resistance and process-specific safety | Material temperature, attachment, redundancy and operating class |
| Power and energy equipment | Generators, turbines, transformers, nacelles and hubs | Open-winch or double-trolley double girder crane | Heavy component assembly and maintenance with precise movement | Load geometry, lifting points, synchronized motion and maintenance lift |
| Paper and process plant | Rolls, drums, motors, pumps and production equipment | Electric-hoist or multi-trolley double girder crane | Wide coverage in humid, dusty or corrosive service | Environment, trolley count, maintenance access and protection level |
| Bulk material handling | Ore, coal, biomass, waste, clinker and slag | Grab double girder crane | Repeated loading, unloading and stockpile transfer | Bulk density, grab volume, fill factor, cycle target and hopper geometry |
| Warehouse and automated storage | Coils, dies, long products, pallets and production stock | Automated or semi-automated double girder crane | Repeatable inventory movement and integration with plant controls | Storage map, throughput, positioning, traffic zones and recovery mode |
Hazardous areas, molten metal, outdoor exposure, high temperature, coastal corrosion, clean production and seismic conditions require project-specific engineering. A standard workshop crane should not be reclassified by changing only the motor enclosure or surface coating.
Project Case: 43-Crane Offshore Wind Manufacturing Program
A large offshore wind manufacturing program required coordinated handling of nacelles, hubs, blades and related components. The first phase included 43 double girder cranes installed and placed into operation. The equipment program combined high-capacity lifting, multiple hooks, controlled low-speed motion and lifecycle monitoring.
The flagship configuration was rated 500+250/32 t and used two trolleys for individual or coordinated operation. Project records specify multi-hook synchronization error within 2 mm and electronic anti-sway control limiting swing angle to within ±0.5°. Automatic speed adjustment matched travel behavior to load condition.
The engineering value lies in system coordination rather than capacity alone. Load geometry, lifting points, trolley separation, bridge stiffness, synchronized motion, runway reactions, operator visibility and process interlocks were treated as one handling system. The case demonstrates the scalability of double girder architecture from standard electric-hoist cranes to major engineered lifting equipment.
PROJECT PHASE
43 Cranes
FLAGSHIP CONFIGURATION
500+250/32 t
SYNCHRONIZATION
≤ 2 mm
ANTI-SWAY LIMIT
≤ ±0.5°
Engineering, Manufacturing and Quality Documentation
A double girder overhead crane package should connect approved design inputs to structural fabrication, mechanism selection, electrical integration, inspection and final acceptance. Documentation requirements should be agreed before manufacturing release.
Design Package
General arrangement, hook approaches, wheel loads, runway reactions, deflection basis, mechanism duty, electrical demand and control narrative.
Structural Records
Material identification, welding procedures, welder qualifications, dimensional reports and specified nondestructive examination.
Mechanism Data
Drum, rope, sheave, hook, motor, gearbox, brake, wheel, bearing and lubrication data matched to the declared duty.
Electrical Documents
Single-line diagram, schematics, drive settings, protection coordination, conductor details and interface schedule.
Inspection and Tests
Inspection plan, witness points, dimensions, brakes, limits, alarms, interlocks, no-load testing and contracted load testing.
Handover Package
Final drawings, certificates, test records, manuals, spare-parts list, maintenance schedule and configured parameters.
Installation, Commissioning and Lifecycle Planning
Runway Survey
Verify rail span, elevation, straightness, joint condition, end stops, buffers, conductor route and structural information before final bridge release.
Delivery and Assembly Plan
Define shipping splits, unloading equipment, assembly area, mobile-crane access, roof clearance, work-at-height controls and production shutdown.
Bridge and Trolley Installation
Assemble girders and end trucks to approved tolerances, install the trolley, align drives and confirm clearances before powered travel.
Electrification and Controls
Install conductors, festoons, isolators, grounding, pendant or radio stations, cabin equipment, sensors and plant interfaces.
Functional Commissioning
Verify motor direction, drives, brakes, upper and lower limits, travel limits, buffers, alarms, emergency stop and interlocks without load.
Load and Site Acceptance
Complete required proof, rated-load and operational tests under an approved procedure with calibrated instruments and documented results.
Operator and Maintenance Handover
Transfer operating limits, inspection points, lubrication schedule, troubleshooting logic, spare parts and emergency procedures.
Lifecycle Service Plan
Base inspection and maintenance intervals on actual duty, environment and load history rather than calendar time alone.
Double Girder Overhead Crane Price and Project Cost
Double girder overhead crane price depends on capacity, span, lifting height, working class, trolley type, motion speeds, control system, runway scope, installation country and acceptance requirements. Current North American installed-market examples provide budget context only and are not fixed Henan Mine Crane prices.
| Budget Item | Indicative Market Position | Typical Scope | Main Cost Drivers | Commercial Control |
|---|---|---|---|---|
| 5 t double girder installed benchmark | Around US$60,000 | General double girder bridge under the published regional conditions | Span, lift, trolley type, runway, controls, labor and access | Confirm runway, freight, testing and structural work |
| 10 t double girder installed benchmark | Around US$100,000 | General double girder bridge under the published regional conditions | Duty, speed, runway, electrical scope, installation and region | Not a fixed international supply price |
| General electric-hoist double girder crane | Project quotation | Bridge, end trucks, hoist trolley, electrification and documents | Capacity, span, lift, duty, headroom, voltage and destination | Separate equipment supply from site services |
| Open-winch heavy-duty double girder crane | Project quotation | Engineered trolley, reeving, brakes, access platforms and controls | Load spectrum, mechanisms, redundancy, speeds and process risk | Compare the complete technical scope |
| Runway and support structure | Separate project item | Rails, runway beams, brackets, columns, bracing and foundations | Wheel loads, travel length, column spacing and building capacity | State design, supply and installation responsibility |
| International delivery and site services | Separate project item | Packing, freight, erection, commissioning, load test and training | Shipping dimensions, destination, local labor, access and test weights | State trade term, taxes, permits and exclusions |
Price normalization: compare bridge structure, trolley, hoisting mechanism, runway steel, electrification, controls, documentation, packing, freight, erection, commissioning, load testing, training, spare parts and exclusions as separate line items.
Information Required for a Double Girder Overhead Crane Quote
A technically comparable quotation requires operating, load, building and commercial information together. Dimensioned plans, runway drawings, load sketches and site photographs should accompany the following data.
Load Data
Maximum and normal mass, dimensions, center of gravity, lifting points, rigging, attachment weight and any future load allowance.
Crane Geometry
Runway rail-center span, travel length, rail elevation, required lift, hook approaches, building section and overhead obstructions.
Duty and Throughput
Lifts per hour, shifts, annual hours, load spectrum, full-load frequency, travel distance and production consequence.
Runway and Building
Rail profile, runway beams, column spacing, brackets, allowable reactions, foundation data and existing structural condition.
Hoisting Arrangement
Electric hoist or open winch, main and auxiliary hooks, trolley quantity, reeving, lifting speeds and synchronization requirement.
Controls and Safety
Pendant, radio or cabin operation, variable-frequency drives, positioning, anti-sway, collision control and required monitoring.
Environment and Power
Voltage, frequency, phase, ambient temperature, dust, humidity, corrosion, hazardous area and indoor or outdoor exposure.
Delivery Boundary
Destination, trade term, runway scope, installation, inspection, testing, training, spare parts, documentation language and schedule.
Double Girder Overhead Crane FAQ
When is a double girder overhead crane preferred?
Double girder construction is normally considered for higher capacities, longer spans, demanding duty, improved hook height, open-winch trolleys, multiple hooks, walkways or process-specific attachments.
Is a double girder crane always more expensive than a single girder crane?
The bridge normally has greater structural weight and more complex trolley arrangements. Total project value depends on whether the double girder design avoids building changes, improves hook height or supports duty that a single girder crane cannot provide.
What is the difference between an electric-hoist and open-winch double girder crane?
An electric hoist is a packaged lifting unit suited to defined general-duty ranges. An open-winch trolley separates drum, motor, gearbox, brakes and reeving for higher capacity, heavier duty, redundancy or process customization.
Can a double girder overhead crane have two trolleys?
Yes. Two trolleys can operate independently or in coordinated modes for long loads, rotation and multiple pick points. Combined capacity, load sharing, trolley collision limits and control authority require definition.
Does double girder construction improve lifting height?
A top-running trolley can travel above or between the girders and often places the hook closer to roof level. Actual hook height depends on rail elevation, girder depth, trolley envelope, hook block and maintenance clearance.
What working class is required?
Working class follows the load spectrum, lifts per hour, travel, shifts and annual service. The published general electric-hoist family covers A3–A6; process or high-duty cranes require separate mechanism and crane classification.
Can an existing runway support a new double girder crane?
Only after structural verification. The assessment should use actual crane self-weight, wheel loads, trolley position, lifted load, impact, lateral forces, rail condition and support capacity.
How much does a double girder overhead crane cost?
Installed-market examples place a general 5 t system near US$60,000 and a 10 t system near US$100,000 under stated North American conditions. International projects require quotations based on complete equipment and site scope.
Which information has the greatest effect on price?
Capacity, span, lift, duty, trolley architecture, speed, runway length, controls, environment, structural work, freight, installation access and testing boundary create the largest cost differences.
What should a final quotation include?
The quotation should identify parameters, working class, mechanisms, runway reactions, control system, safety devices, documents, tests, packing, freight, installation, commissioning, training, spare parts, schedule and exclusions.
Related Overhead Crane Products
Compare alternative bridge structures and process configurations after capacity, span, hook height, duty, load geometry, runway and operating environment have been defined.
Single-Girder Overhead Crane
Lower-self-weight bridge configuration for general workshops, warehouses, assembly areas and maintenance bays.
Multi-Support Double-Girder Underhung Crane
Large-span suspended system for aircraft hangars, assembly buildings and facilities requiring clear production floors.
Explosion-Proof Bridge Crane
Project-specific crane for formally classified gas or dust environments requiring matched protection and certification.
Double-Girder Casting Crane
Heavy-duty metallurgical configuration engineered for molten-metal handling, high temperature and severe service.
Electromagnetic Bridge Crane
Magnetic handling system for plates, billets, profiles and scrap with project-specific power continuity and controls.
Three-Trolley Electric Hoist Bridge Crane
Multi-trolley arrangement for long workpieces, production handling and maintenance tasks requiring several pick points.
Request a Double Girder Overhead Crane Quote
Submit the load list, capacity, span, lifting height, runway drawings, operating duty, trolley requirement, motion speeds, control mode, power supply, environment, installation boundary and destination. Henan Mine Crane will prepare a coordinated technical configuration and commercial quotation.