分类： Crane Technology

01 · Single-Girder Electric Hoist Gantry

One main girder carries an underslung electric wire-rope or chain hoist. The arrangement controls deadweight and equipment cost for general manufacturing, warehousing, assembly and maintenance duties.

02 · Double-Girder Electric Hoist Gantry

Two girders provide greater structural stability, improved lifting-height utilization and broader capacity potential while retaining the service simplicity of a packaged electric hoist or sitting trolley.

03 · Double-Girder Winch-Trolley Gantry

A top-running open-winch trolley supports higher load, longer lift, faster speeds, heavier duty, auxiliary hooks and redundant machinery arrangements required by demanding industrial processes.

04 · Electric Semi-Gantry Crane

One end carriage travels on an elevated building runway and the opposite end travels on a ground rail. The layout serves workshop edges, production bays and indoor-to-outdoor transfer routes.

05 · L-Type Electric Gantry Crane

An offset L-shaped leg improves side clearance for long materials and permits cantilever handling. Hook, grab or magnetic attachments can be integrated for the approved operating duty.

06 · Motorized Mobile Gantry Crane

Powered wheels support controlled relocation in maintenance or assembly areas. Capacity, travel surface, gradients, wheel loads, wind exposure and safe movement procedures limit the permissible application.

Double-Girder Electric-Hoist Product Family

Henan Mine Crane product data covers 3–50 t capacity, 7.5–35 m span, 4–30 m lifting height and A3–A5 working class. Final limits depend on the approved configuration and project standard.

Single-Girder Semi-Gantry Product Family

Product data covers 1–32 t capacity, 6–35 m span, 4–20 m lifting height and A3–A5 working class. The elevated runway and ground rail form part of the interface review.

L-Type Electric-Hoist Product Family

Product data covers 1–32 t capacity, 6–35 m span, 4–20 m lifting height and A3–A5 working class, with cantilever and attachment options evaluated for the operating case.

Load and Hoist Protection

Overload limiting, upper and lower travel limits, brake monitoring where required, rope guidance, hook safety latch and controlled low-speed positioning protect the vertical lifting motion.

Travel Protection

End limits, buffers, audible and visual warnings, emergency stops, travel brakes and anti-collision functions are selected for route length, traffic and multiple-crane operation.

Variable-Frequency Control

VFD control provides progressive acceleration, reduced load swing, controlled approach and lower mechanical shock. Speed ranges are matched to motor cooling and process demand.

Outdoor Wind Security

Anemometers, operational wind limits, rail clamps, storm anchors, parking positions and site procedures control wind risk for rail-mounted outdoor cranes.

Electrical Protection

Isolation, short-circuit and overload protection, phase monitoring, earthing, enclosure selection and cable management are coordinated with the plant supply and environment.

Skew and Position Control

Long spans, high travel speeds or uneven wheel loading may require encoder feedback, independent-drive coordination, anti-skew logic or position supervision.

Box girders provide torsional stiffness and controlled deflection for industrial rail-mounted cranes. A single-girder bridge reduces self-weight and wheel reactions, while a double-girder bridge supports top-running trolley arrangements, improved hook height and heavier service. One leg may be rigid and the opposite leg flexible on longer spans to accommodate thermal movement and rail tolerances.

Headroom is governed by the relationship between rail level, bridge depth, trolley or hoist position, hook approach and the highest required load position. Raising the overall frame is not always the most economical solution because leg height, wind moment, stability, shipping and erection requirements also increase. A section drawing should confirm vertical and side clearances before fabrication.

Common electrical feeds include cable reels, festoon systems, conductor bars and project-specific trailing-cable arrangements. The selected method follows runway length, travel speed, outdoor exposure, maintenance access and plant connection point. Standard product families can be configured for 380 V, 50 Hz or project supplies within 220–660 V and 50/60 Hz, subject to electrical review.

Documented Heavy-Lift Application

Henan Mine Crane supplied a 700 t project-specific gantry crane for construction work associated with the Zhangjiagang Yangtze River Bridge. The system handled large steel tower sections, placing the lifting operation far beyond the duty of a standard packaged electric-hoist gantry crane.

The case demonstrates the engineering sequence required when load geometry, lifting points, construction stages and site boundaries control the crane concept. Structural arrangement, lifting machinery, electric drives, travel coordination, foundations, erection method and acceptance planning must be treated as one system. Rated tonnage alone cannot define a heavy-lift gantry.

The same discipline applies at smaller capacities. A reliable electric gantry crane proposal should identify the suspended load, work cycle, coverage, duty, wind basis, rail interface, power feed, control method and testing boundary before price and delivery are fixed. The 700 t installation represents a specialized project application and is not a standard-range price example.

A commercial proposal should identify the design basis and the documents delivered with the equipment. Typical engineering outputs include the general arrangement, wheel loads, maximum rail reactions, foundation interface, power demand, motor list, single-line diagram, control description and shipping split. Final documentation follows the contract, destination rules and acceptance authority.

Manufacturing control normally covers material identification, welding procedures, dimensional inspection, machining, assembly, coating preparation and electrical-panel verification. Non-destructive examination, third-party witness points and material certificates are included when specified in the inspection and test plan. Factory testing should record hoist, trolley and crane motions, limits, brakes, controls and protective functions available before shipment.

Procurement review should confirm drawing approval stages, deviation handling, document language, spare-parts list, test records and release criteria. This evidence establishes traceability between the approved specification and the delivered crane and prevents essential documentation from becoming an undefined post-order item.

Before Delivery

Approve drawings, rail details, wheel loads, electrical connection, access route, lifting plan, temporary works and storage protection. Confirm whether girders arrive as complete units or shipping sections.

Erection and Alignment

Assemble the structure under an approved lifting method, align rails and end carriages, verify diagonal dimensions, set buffers and anchors, route cables and complete electrical termination.

Commissioning and Acceptance

Check insulation, earthing, phase sequence, limits, brakes, controls, warning devices and no-load motions before functional and load testing under the governing acceptance plan.

Operating Handover

Provide operating instructions, maintenance schedules, lubrication points, electrical drawings, parts information and training for operators and maintenance personnel.

Planned Maintenance

Inspect ropes or chains, hooks, brakes, wheels, rails, fasteners, structure, electrification and protective devices at intervals based on duty, environment and governing requirements.

Lifecycle Provision

Define critical spares, consumables, remote technical support, inspection access and future relocation requirements during procurement rather than after commissioning.

Load and Handling Task

Maximum gross suspended load, normal load, dimensions, center of gravity, lifting points, attachment, pick location, set-down location and required positioning accuracy.

Crane Geometry

Rail-center span, lifting height, rail elevation, runway length, cantilever reach, end approaches, headroom, side clearances and any future expansion.

Operating Duty

Lifts per hour, average load, full-load frequency, travel distance, shifts per day, annual hours, target speeds and expected service life.

Site and Environment

Indoor or outdoor location, temperature, wind, rain, humidity, dust, corrosive exposure, altitude, floor or soil data and available installation access.

Electrical and Controls

Voltage, frequency, phases, plant connection point, pendant, radio or cabin control, VFD requirements, plant interfaces and automation functions.

Commercial Boundary

Delivery destination, trade term, governing standard, drawing and test requirements, inspection authority, installation scope, load-test responsibility and required delivery date.

What is the difference between an electric gantry crane and a motorized gantry crane?

Electric gantry crane is the broader term and may describe powered hoisting, powered trolley travel and powered long travel. Motorized gantry crane usually emphasizes powered relocation or long travel, including mobile or rail-mounted arrangements.

Is an electric gantry crane suitable for outdoor operation?

Yes, when wind basis, storm parking, rail clamps or anchors, drainage, corrosion protection, enclosure ratings, cable system and temperature limits are engineered for the site. Standard indoor electrical equipment should not be assumed suitable outdoors.

When is a double-girder configuration required?

Double girders are considered when capacity, span, lifting height, hook approach, duty, trolley arrangement or attachment exceeds the practical range of a single-girder electric-hoist system. Final selection follows calculation and lifecycle requirements.

Can an electric gantry crane operate without ground rails?

A mobile unit can operate on suitable wheels over an approved surface, but capacity, floor loading, slope, traction, stability, travel speed and wind exposure impose limits. Industrial repetitive travel normally favors a properly aligned rail system.

Which control method is available?

Pendant, radio remote and operator cabin controls are available. Variable-frequency drives, PLC functions, anti-sway, anti-collision and position supervision can be added when the handling process and risk assessment require them.

How is the required electrical power calculated?

Power demand follows hoist, trolley and crane motor ratings, simultaneous-motion assumptions, duty, acceleration, auxiliary loads and starting method. The proposal should state connected load, supply data and the crane-to-plant connection boundary.

What information has the greatest effect on price?

Capacity, span, lift, duty, hoist or winch-trolley type, runway length, outdoor package, control complexity, rails, foundations, shipping dimensions and installation scope create the largest differences.

How long does manufacture and commissioning take?

Schedule depends on engineering complexity, drawing approval, material procurement, fabrication, inspection, shipping route, site readiness and acceptance requirements. A committed date should follow confirmation of the final technical and commercial scope.

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

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.

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.

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.

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.

View Project Application →

PROJECT PHASE

43 Cranes

FLAGSHIP CONFIGURATION

500+250/32 t

SYNCHRONIZATION

≤ 2 mm

ANTI-SWAY LIMIT

≤ ±0.5°

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.

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.

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.