Multiple Point Underhung Bridge Crane 5 Ton 9m+9m H6m | 3 Support Points

A multiple point underhung bridge crane — also called a multi-point underhung crane or multi-support underhung bridge crane — is a crane with more than two support points along the bridge. Instead of only supporting the bridge at the two ends, the bridge is supported at additional intermediate points. This crane has 3 support points — left, middle, and right. Multiple point design is used because:

• Wide span support: A single rail on each side would not provide enough support for the 18m bridge — the middle support point supports the center of the bridge
• Reduced bridge deflection: With three support points, the bridge deflects much less than a two-point design at the same span — the effective span of each section is only 9m instead of 18m
• Better load distribution: The 5t load is distributed across three support points, reducing the wheel load on each one
• Higher rigidity: The middle support point adds a third support that resists bending, allowing the bridge to span 18m with acceptable deflection
• Long load handling: The wide 18m bridge is ideal for handling long loads that require a wide hook span
• Lower bridge weight: Because the effective span is reduced, the bridge section can be lighter than a two-point design at the same total span

Multiple point underhung bridge cranes are specialized solutions for wide bays that require a continuous long bridge with acceptable deflection.

The 3 support points with 9m rail spacing work as follows:

• Left support point: The left end carriage runs on the left rail
• Middle support point: The middle end carriage runs on the middle rail, supporting the center of the bridge
• Right support point: The right end carriage runs on the right rail
• Three rails with 9m spacing: Three rails are installed at the ceiling, with 9m between each rail — the left rail is 9m from the middle rail, and the middle rail is 9m from the right rail
• Total 18m span: The distance from the left rail to the right rail is 18m (9m + 9m)
• 20m girder: The bridge girder is 20m total length — 18m of span plus 1m overhang on each side for the end carriages

This three-point design with 9m rail spacing is a highly specialized engineering solution for very wide bays requiring a continuous long bridge with acceptable deflection.

The 20m total girder length and 18m span work together as follows:

• 18m span: The distance from the left rail to the right rail is 18m (9m + 9m)
• 20m total girder length: The girder is 20m long — 18m of span plus 1m overhang on each side
• 1m overhang: The overhang on each side accommodates the end carriages, which sit on the runway rails
• Hook approach: The overhang also determines how close the hook can get to the runway rail (hook approach)
• Wheel load: The 1m overhang affects the wheel load distribution — the wheel load accounts for this overhang and the 5t live load

The 20m total girder length with 18m span and 1m overhang on each side is a standard layout for a wide-span multiple point underhung bridge crane.

The ceiling mounted under running design is used for this multiple point crane because:

• Saves headroom: Because the crane is suspended directly from the roof or ceiling structure and runs on the bottom flange of the runway beam, the crane fits into buildings with limited vertical clearance
• Maximizes hook height: The underhung design allows the hook to be raised closer to the ceiling, maximizing the available lifting height
• No floor columns: The entire floor area beneath the crane is free for operations, materials, and equipment
• Ideal for existing buildings: Retrofitting a top running crane into an existing building often requires major structural work — the ceiling mounted design can be installed more easily
• Multiple point support: The ceiling structure can support multiple suspension points along the bridge
• Better hook approach: The hook can get closer to the wall and to the runway ends than a top running crane

The trade-off is that the ceiling structure must be strong enough to support the crane, hoist, runway beam, and rated load at all three support points. If the ceiling structure is not strong enough, a freestanding underhung crane with steel columns can be used instead.

Nine numbers on this multiple point underhung bridge crane drawing must match your workshop, or the crane will not fit or operate correctly:

If any of these differ from your workshop, tell Yuantai before ordering — each change affects price and lead time on the multiple point underhung bridge crane.

No — this multiple point underhung bridge crane is configured for indoor workshop use as a multi-point ceiling mounted under running crane or low headroom overhead crane. The crane is suspended from the roof or ceiling structure. Outdoor use would require:

• Different crane type: A gantry crane with ground rails and A-frame legs is usually more suitable for outdoor use
• Weather protection: Outdoor-rated electrical enclosures (IP55+) and anti-corrosion treatment
• Wind load design: Anti-wind devices and anchoring — critical for a wide 18m bridge where wind loads are significant
• Rain cover: Protect the crane, hoist, and electricals from rain and snow

For outdoor applications, consult Yuantai Cranes for a suitable gantry crane or a weather-protected multiple point crane solution.

To avoid surprises at installation, these items are outside the multiple point underhung bridge crane supply scope unless you specifically add them:

• Runway rails and rail fasteners — three rails required
• Ceiling suspension rods, tube brackets, or mounting hardware at all three support points
• Roof truss or ceiling beam reinforcement — must support wheel load at all three support points
• Building structural verification for the 5t capacity at 6m lift and 18m span
• Site power supply up to the crane isolator — 380V 50Hz
• Electrical panel installation space and cable routing along the runway
• Erection crane and site lifting equipment for three-support-point installation
• Local electrical connection and permits

Because the multiple point underhung bridge crane operates with three support points at a wide 18m span, the ceiling structure and three-rail alignment are critical — the roof trusses or ceiling beams must support the wheel load at all three support points, and all three rails must be precisely aligned with 9m spacing for the crane to travel smoothly. Yuantai can provide ceiling load drawings, runway load drawings, and installation guidance as optional items.

Send these twelve items and Yuantai will issue a free custom multiple point underhung bridge crane CAD drawing and proposal within 24 hours:

1. Required lifting capacity (t) — e.g., 5t
2. Crane span (m) — e.g., 9m + 9m
3. Number of support points required (e.g., 3 support points)
4. Number of rails required (e.g., 3 rails)
5. Rail spacing (m) — e.g., 9m between each rail
6. Number of end carriages (e.g., 3 end carriages)
7. Required lifting height (m) — e.g., 6m
8. Ceiling or roof structure details (truss spacing, beam capacity, mounting method)
9. Building clear height and roof structure capacity
10. Power supply (V / Hz / Ph) — e.g., 3P 380V 50Hz
11. Duty class — e.g., A3
12. Control requirement — e.g., pendant + remote

The more complete the list, the faster and more accurate the multiple point underhung bridge crane drawing and quote.

This published multiple point underhung bridge crane drawing and 3D rendering are a free technical reference — you may use them to plan your workshop and check fit. A project-specific multiple point underhung bridge crane GA drawing and 3D model are also free for standard configurations. A design fee may apply only for complex multiple point conditions, non-standard spans, specialized rail spacing, ceiling suspension design, or customized multi-support point design. The multiple point underhung bridge crane drawing remains the property of Yuantai Cranes: unauthorized copying, use, or manufacturing without written authorization is strictly prohibited.