Double Hook Overhead Crane 20 Ton Hook & 10 Ton Hook

Imagine a machinery factory that handles large machine bases, steel frames, motors and gearboxes.

The operator can use the 20-ton main hook for a heavy machine assembly and the 10-ton auxiliary hook for smaller components.

Here are some examples:

These are illustrative loads, not actual customer lifting records. The weight of the lifting attachment must also be included when checking the permissible load.

Using the auxiliary hoist for suitable lighter loads means the operator does not need to use the 20-ton main hoist for every lifting task.

Can both hooks lift the same load at the same time?

This depends on the crane design.

If the factory needs both hooks to lift or turn one long component, this requirement must be specified before manufacturing. The manufacturer needs to check the load distribution, hook spacing, trolley structure and hoist controls.

The rated capacities of the two hoists cannot simply be added together. A 20-ton main hoist and a 10-ton auxiliary hoist do not automatically give the crane a 30-ton lifting capacity.

The main and auxiliary hooks are arranged on the same trolley assembly. Their relative positions are determined by the trolley design.

This is important when handling long steel structures, machinery frames or components with lifting points at different locations.

Buyers should check the distance between the hooks, their positions across the bridge, and the available hook travel on the general arrangement drawing. These dimensions determine whether both hooks can reach the required lifting points.

Typical loads: machine bases, gearboxes, motors, housings and assembled machinery.

Machinery factories often need to lift large assemblies as well as individual components.

A large machine base may require the 20-ton main hook, while motors, gearboxes and smaller components can be handled by the 10-ton auxiliary hook.

This arrangement is useful during machine assembly, equipment installation and workshop maintenance.

Related applications:

• 20 ton EOT crane for machinery manufacturing
• Overhead crane for machine assembly workshop
• Double hook overhead crane for industrial equipment
• 10 ton auxiliary hoist for machinery handling

Typical loads: equipment frames, hydraulic components, large fabricated parts and heavy assemblies.

Manufacturers of construction equipment, agricultural machinery and other industrial equipment often handle components of different weights in the same workshop.

The main hook can lift heavy frames and assembled structures, while the auxiliary hook handles suitable medium-weight components.

A double girder overhead crane with two hoists can be considered when both lifting capacities are needed within the same crane coverage area.

Typical loads: steel plates, processed sections, tooling, fabricated components and production equipment.

Steel processing workshops may use the main hook for heavy tooling, large assemblies and production equipment. The auxiliary hook can handle lighter components and other materials within its rated capacity.

The lifting attachment also needs to be considered.

For example, when lifting steel plates with a spreader beam, the beam's own weight must be included in the total suspended load. The same applies to plate clamps, magnetic lifters and other lifting devices.

If a 20-ton crane uses a lifting beam weighing 1.2 tons, the remaining capacity available for the payload is 18.8 tons, subject to the crane and lifting equipment ratings.

Typical loads: pumps, motors, gearboxes, machine parts and replacement equipment.

Maintenance work does not always require a 20-ton lifting capacity.

The 10-ton auxiliary hook can handle suitable motors, pumps and replacement components, while the main hook remains available for heavier equipment installation and replacement.

This arrangement is useful in factories where production and maintenance activities share the same overhead crane system.

With a 20/10 ton double girder overhead crane, both hoists are installed on one crane bridge.

The main and auxiliary hooks travel with the same bridge along the runway. The operator selects the appropriate hoist for the lifting task.

With two separate overhead cranes, each crane has its own bridge girders, end carriages, travelling motors and hoisting mechanism.

If both lifting capacities are needed in the same working area, one crane with two hoists can reduce the amount of duplicated crane equipment.

The runway is an important part of the total overhead crane system.

For one 20/10 ton double girder crane, the runway is designed according to the crane's own weight, trolley weight, rated loads, wheel arrangement and operating conditions.

For two separate cranes, the runway must be checked for the wheel loads of both cranes and the relevant operating load combinations. The possibility of the cranes approaching each other on the same runway also needs to be considered.

A double girder crane does not automatically require a lighter runway than two single girder cranes. The actual comparison depends on the engineering calculations.

Before purchasing, request the manufacturer's wheel load diagram. This information is needed to check the runway beams, rails, supporting columns and connections.

A double hook overhead crane gives the operator access to two lifting capacities within one crane coverage area.

For example:

• Use the 20-ton main hook to lift a heavy machine assembly.
• Use the 10-ton auxiliary hook to move smaller production components.
• Move the bridge crane along the runway to serve different workstations.

The operator can select the appropriate hoist without having to move a second crane into position.

Two separate overhead cranes require two complete bridge structures and two sets of crane travelling mechanisms.

A 20/10 ton double girder crane integrates both lifting functions into one bridge structure.

This can reduce duplicated equipment, simplify the crane arrangement and make maintenance management more straightforward.

There are still two hoisting mechanisms to maintain. Each has its own motor, brake, wire rope, drum and lifting components, so the auxiliary hoist should not be overlooked in the maintenance plan.

This is where the two options differ most.

With one double girder crane and two hoists, both hooks travel with the same bridge. They cannot move independently along the runway.

With two separate overhead cranes, each bridge can travel independently, subject to the runway layout and collision protection arrangements.

If the 20-ton and 10-ton lifting jobs take place in different locations at the same time, two separate cranes may be more suitable.

If both lifting capacities are needed in the same working area and independent crane movement is not necessary, a 20/10 ton double girder overhead crane is worth considering.

If two production teams need to operate cranes independently, or if the lifting jobs take place in different areas, two separate overhead cranes may be a better fit.

The decision should be based on the production layout and lifting frequency, not simply on the crane capacities.

Double girder overhead cranes are commonly used for higher-capacity lifting applications, particularly in steel plants, machinery factories, equipment manufacturing and heavy industrial workshops.

They can accommodate different trolley and hoist arrangements, depending on the lifting capacity, span and duty requirements.

For this Philippines project, the double girder configuration provides the required structure for the 20-ton main hoist and 10-ton auxiliary hoist.

A double girder overhead crane can be designed with:

• Main and auxiliary hoists.
• Two hoists with different rated capacities.
• Different lifting heights.
• Different hook positions.
• Special lifting beams and attachments.
• Application-specific trolley arrangements.

The actual hook coverage depends on the trolley design and its travel limits.

Buyers should check the general arrangement drawing to make sure the two hooks can reach the required lifting positions.

The NLH is a low-headroom double girder overhead crane configuration.

Its hoist and trolley arrangement is designed to make better use of the available vertical space compared with a conventional trolley arrangement.

This is useful when the factory needs a high hook lifting position but has limited space between the runway and roof structure.

For the Philippines project, the required lifting heights are more than 14 m. The available headroom, trolley height and hook approach therefore need to be checked carefully.

Rather than comparing crane model names alone, buyers should ask for the actual dimensions on the general arrangement drawing.

The main and auxiliary hoists may have different lifting speeds.

The main hoist generally handles heavier loads, while the auxiliary hoist may be used more frequently for lighter components.

The required speeds depend on the production cycle, load weight and positioning accuracy.

For applications requiring smooth starting, stopping and accurate load positioning, variable frequency drive (VFD) control can be considered.

When comparing quotations, ask for the following details separately:

• Main hoist lifting speed.
• Auxiliary hoist lifting speed.
• Trolley travelling speed.
• Crane travelling speed.
• Whether variable speed control is included.

Crane duty classification depends on how frequently the crane operates and the loads it handles.

A maintenance workshop that performs occasional heavy lifts has different requirements from a production plant that handles materials throughout several shifts.

The manufacturer should assess:

• Average lifting load.
• Maximum lifting load.
• Number of lifting cycles.
• Daily operating hours.
• Load spectrum.
• Expected service life.

The main and auxiliary hoists may also have different usage patterns. For example, the auxiliary hoist may perform many more lifting cycles than the main hoist.

The duty classification should reflect these actual operating conditions under the selected ISO, FEM or GB design standard.

The distance between the main and auxiliary hooks affects the types of loads the crane can handle.

This is particularly important for long steel structures, machinery frames and components with multiple lifting points.

Check the hook center distance, hook positions and available trolley travel before confirming the design.

For a new or existing factory, the following dimensions and structural information should be provided:

• Crane span and runway rail gauge.
• Runway rail type and size.
• Runway beam dimensions.
• Supporting column arrangement.
• Maximum allowable wheel loads.
• Floor-to-rail elevation.
• Roof structure and overhead clearance.
• Required hook approaches.
• Available maintenance access.

The crane manufacturer should provide the wheel load data for structural verification.

This Philippines project uses a 400V, 60Hz, 3-phase power supply.

The hoisting motors, travel motors and electrical control system should be selected to match the actual factory power supply.

Buyers should also specify the preferred operating method:

• Pendant control.
• Radio remote control.
• Operator cabin.

For a double hook overhead crane, the controls should clearly distinguish between the main and auxiliary hoists. Each hoist also needs the appropriate overload protection, upper and lower limit switches, braking system and other required safety devices.

A standard 20-ton overhead crane has one 20-ton main hoist.

A 20/10 ton overhead crane has an additional 10-ton auxiliary hoist. This gives the factory another lifting option for medium-weight materials and smaller components.

The auxiliary hoist adds its own motor, brake, wire rope and lifting mechanism, so the trolley and crane structure must be designed for the additional equipment.

Not automatically. The two rated capacities cannot simply be added together to obtain a 30-ton lifting capacity.

If both hooks need to support the same load, the crane must be specifically designed and approved for that operation. The manufacturer needs to check the combined loading, load distribution, hoist synchronization and structural capacity.

Yes. A 20-ton double girder overhead crane can handle machine bases, industrial equipment, heavy components and assembled machinery.

With a 10-ton auxiliary hoist, the crane can also handle suitable medium-weight components within the same working area. This arrangement is useful in machinery manufacturing, assembly and maintenance workshops.

Choose one 20/10 ton double girder crane when both lifting capacities are needed in the same working area and the two hoists do not require independent crane travel.

Consider two separate overhead cranes when different production areas need independent operation or when two lifting operations must take place at different positions simultaneously.

The main difference is whether the two lifting operations need independent crane movement.

The manufacturer needs the main and auxiliary hook capacities, crane span, lifting heights, runway dimensions, power supply, working frequency and load details.

Workshop drawings and photographs are also useful, particularly when the crane will be installed on an existing runway.

A conventional QD double girder crane generally uses an open winch trolley mounted above the bridge girders.

The NLH is a low-headroom configuration designed to reduce the vertical space occupied by the hoisting mechanism.

The actual headroom depends on the crane capacity, lifting height and trolley arrangement. Buyers should compare the general arrangement drawings and hook approach dimensions before selecting the crane.

Yes, provided the motors and electrical components are selected for 400V, 60Hz, 3-phase operation.

The voltage and frequency should be confirmed before manufacturing. This is particularly important when purchasing an overhead crane from China, where standard electrical configurations may differ from the factory's actual power supply.

The price depends on the crane structure, main and auxiliary hoists, span, lifting heights, working duty, lifting speeds, electrical components and control system.

Transportation, runway beams, installation and commissioning also affect the total project cost.

A 20/10 ton NLH double girder crane should be quoted according to the complete technical specification rather than compared directly with a standard 20-ton single-hoist crane.

The runway must be checked against the new crane's maximum and minimum wheel loads.

Ask the manufacturer for the wheel load diagram and relevant crane dimensions. A structural engineer should verify the runway beams, rails, supporting columns and connections before installation.

The available headroom, hook approach, rail gauge and installation clearance should also be checked against the approved crane drawings.