Lifting capacity (also called rated load or rated capacity) refers to the maximum weight the crane is designed to lift safely under normal operating conditions. For example, a 10-ton overhead crane can safely lift loads up to 10 tons, including the hook block and lifting attachments.

The rated load normally includes:

• The weight of the lifted material
• The hook block or lifting hook
• Any lifting devices, such as slings, lifting clamps, magnets, grab, etc.

Typical capacity ranges:

• Light workshop cranes: 1 – 5 tons
• General manufacturing cranes: 5 – 20 tons
• Heavy fabrication cranes: 20 – 50 tons
• Steel mill cranes: 50 – 200 tons
• Special heavy-duty cranes: up to 500 tons

Safety factors are built in to account for dynamic loads, motor torque, braking, and structural strength. A practical rule: choose a crane rated 20–30% above typical load.

The crane span is the horizontal distance between the centers of the runway rails. Span determines how wide the crane bridge must be to cover the work area.

Key factors affecting span:

• Distance between factory columns
• Position of runway beams
• Width of the production area
• Clearance for equipment or vehicles

Typical ranges:

• Small workshops: 7.5 – 15 m
• Medium factories: 15 – 25 m
• Large plants: 25 – 35 m

Longer spans usually require double girder designs for stability.

Lifting height is the vertical distance the hook can travel from floor to the highest point. Factors affecting height include stored material height, equipment size, vehicle clearance, building roof, and hoist type.

Typical ranges:6 – 30 m. Most general cranes operate within 6–18 m.

• Higher lifting for stacked steel coils
• Lower lifting for assembly workshops

Clear definition of lifting height early ensures the crane reaches all working areas.

Duty classification reflects how often and how hard a crane works. Selecting the right group reduces wear and maintenance costs.

• A3 – Light Duty: Low frequency, light loads, short shifts. Workshops, small warehouses.
• A4 – Medium Duty: Regular lifting, moderate cycles. Manufacturing, assembly plants.
• A5 – Heavy Duty: Frequent lifting, heavier loads. Metal fabrication, machinery production.
• A6 – High Frequency: Intensive cycles, heavy workloads. Steel processing, automated lines.
• A7 – Continuous Use: Very high frequency, continuous operation. Steel mills, foundries, large ports.

Cranes have three main speeds:

• Hoisting: 3 – 12 m/min depending on single, dual, or high-speed hoists.
• Trolley travel: 20 – 40 m/min, often with VFD for smooth acceleration.
• Bridge travel: 30 – 100 m/min, faster for large production areas.

Speeds affect handling efficiency and positioning accuracy.

Cranes must match local electrical systems. Typical industrial voltages: 220V, 380V, 415V, 440V, 480V. Frequency: 50 Hz or 60 Hz.

Check plant voltage, frequency, and available power. Mismatched specs may need transformers or adjustments.

Common control methods:

• Pendant control: Wired pendant, operator walks with load. Simple, reliable. Good for small cranes, workshops.
• Wireless remote: Operator controls crane from a safe distance. Better visibility, mobility, and safety. Common in warehouses and outdoor operations.
• Cabin control: Operator in bridge-mounted cabin. Used for large cranes, steel mills, container yards. Provides stable, precise control.

The structure of the building often determines what type of crane can be installed and what specifications are possible.

• Runway beams: Must support crane weight, loads, and dynamic forces during operation.
• Column spacing and building width: Determines possible crane span; wider buildings may require longer spans.
• Headroom limitations: Limited ceiling height may require a low-headroom hoist design.
• Runway alignment and installation access: Limited space may influence crane configuration and assembly process.

Manufacturers often review building drawings or structural layouts before finalizing specifications.

The crane's operating environment affects material selection, electrical components, and protective features.

• Indoor vs. outdoor operation: Outdoor cranes may require weatherproof motors, electrical cabinets, and controls.
• Dust and particles: Cement, steel, or mining industries require dust-resistant components and sealed motors.
• Corrosive environments: Coastal or chemical plants need corrosion-resistant materials and protective coatings.
• High or low temperatures: Extreme temperatures require appropriate hoists, lubricants, and electrical systems.

Ignoring environmental conditions can cause premature wear, frequent maintenance, or electrical failures.

The type of material being lifted directly affects crane configuration and lifting equipment.

• Steel coils: Lifted with C-hooks or coil grabs.
• Palletized materials: Standard hooks or lifting frames used for pallets.
• Machinery and equipment: May require lifting beams, slings, or special rigging tools.
• Long materials: Pipes or beams may require spreader beams to balance loads.

Material size, shape, and handling influence:

• Crane capacity
• Hook configuration
• Trolley design
• Safety systems

Suppliers usually request material dimensions, weight, and lifting method before recommending specifications.

The frequency of crane operation affects duty classification and component selection.

• Low-frequency operation: Occasional use; light-duty A3 classification.
• Moderate production use: Regular handling but not continuous; typically A4 duty class.
• High-frequency industrial operation: Steel plants, foundries; usually A5 or A6 duty classification.
• Continuous production environments: Heavy industries; may require A7 duty cranes with reinforced structures.

Insufficient duty classification can lead to rapid wear, frequent breakdowns, and higher maintenance costs.

Practical Tip: Before requesting a quote, provide building layout, lifting capacity, height, material type, daily frequency, and installation environment to ensure accurate specifications.

Determine the maximum load the crane will lift. Include:

• Weight of the heaviest item
• Weight of lifting tools (hooks, clamps, spreader beams)
• Possible bundled loads
• Future production changes

Examples:

• Warehouse with pallets: 1–3 ton crane
• Fabrication shop: 10–20 ton crane
• Steel plants/heavy equipment: 50 tons or more

Include a safety margin to avoid operating continuously at max load.

Crane span is the distance between runway rails.

• Measure distance between runway beams
• Consider clearance for walkways or structures
• Ensure full coverage of working area

Typical spans:

• Small workshops: 7.5–15 m
• Medium factories: 15–25 m
• Large halls: 25–35 m

Wider facilities may use multiple cranes or bays.

Lifting height (hook height) is the vertical distance from floor to the highest safe hook position.

• Consider building height
• Height of load
• Clearance above machines or racks
• Space for rigging equipment

Examples:

• Warehouse: 6–8 m
• Fabrication shop: 10–18 m
• Some plants: above 20 m

Low-headroom hoists may be necessary when ceiling space is limited.

Duty classification defines how often the crane is used and how heavy the loads are:

• A3 – Light duty: Occasional lifting, maintenance, small warehouses
• A4 – Medium duty: General workshops and assembly plants
• A5 – Heavy duty: Fabrication shops and production lines
• A6 – High frequency: Steel processing, machine manufacturing, busy logistics
• A7 – Continuous industrial use: Steel mills, foundries

Correct duty classification prevents premature wear and unexpected downtime.

Operating environment may require special features:

• Indoor or outdoor installation
• Dusty environments (cement, mining)
• High humidity or coastal conditions
• High temperatures (foundries)
• Corrosive chemical environments

Possible adaptations:

• Sealed electrical enclosures
• Corrosion-resistant coatings
• Weather protection covers
• Heat-resistant components

Cranes must match the local electrical system. Typical industrial power supplies:

• 220V / 50Hz or 60Hz
• 380V / 50Hz
• 415V / 50Hz
• 440V / 60Hz
• 480V / 60Hz

Confirm:

• Voltage and frequency
• Three-phase power availability
• Electrical standards used in facility

This avoids major electrical modifications during installation.

Practical Tip: Provide lifting capacity, building width, lifting height, material type, operating frequency, installation environment, and power supply to get accurate manufacturer recommendations.

The lifting capacity is the key specification, as it determines the design of the hoist, bridge, and runway system.

• Span (distance between rails)
• Lifting height
• Duty classification
• Working environment

Selecting capacity first simplifies the selection of other specifications.

Span depends on the building layout:

• Small workshops: 7.5–15 m
• General factories: 15–25 m
• Large production halls: 25–35 m

Proper span ensures safe crane travel without interfering with workflow.

Consider these factors:

• Maximum load weight including lifting tools
• Lifting frequency: occasional vs. continuous
• Bundle size if lifting multiple items together

It is advisable to select a slightly higher capacity than the maximum load to ensure safety and reduce wear.

Duty class defines how intensely the crane will operate:

• A3 – Light duty: Maintenance or occasional lifts
• A4 – Medium duty: General factory use
• A5 – Heavy duty: Frequent production use
• A6–A7 – High duty: Steel mills, heavy fabrication, continuous operation

Choosing the correct duty class ensures long-term durability and safe operation.

Yes. Most cranes can be customized for your facility and operational needs:

• Special lifting heights or spans
• Weatherproof or dust-resistant designs
• Control types: pendant, wireless, or cabin
• Hoist and trolley speed adjustments

Providing detailed information ensures the crane fits your workflow and environment.