QD Double-Girder Bridge Crane Models, Specs & Pricing
The QD-type double-girder bridge crane is one of the most common heavy-duty lifting solutions in industrial plants and warehousing facilities. It features a twin-main-girder box structure paired with an independent trolley hoist, offering lifting capacities from 5 t to 320 t and spans up to 35 m. Compared to single-girder cranes, the QD series delivers superior load-bearing capacity, operating stability, and work duty classification, making it well-suited for heavy-load material handling in metallurgy, machinery manufacturing, hydropower stations, ports, and large-scale warehousing. This article provides a systematic overview of the QD-type double-girder bridge crane across five key dimensions—product structure, technical parameters, price reference, application scenarios, special equipment management, and selection key points—to help procurement professionals make well-informed decisions for various tonnage requirements.
Fig. QD-type double-girder bridge crane structure (twin main girders + trolley hoist + operator cabin)
QD-Type Product Line Overview
The QD-type double-girder bridge crane belongs to the heavy-duty series of general purpose bridge cranes (overhead travelling cranes). It consists of five major assemblies: the bridge girder (twin main girders + end carriages), the trolley hoist, the crane travel mechanism, the trolley travel mechanism, and the electrical control system.
Unlike the LD-type single-girder crane, which uses an electric hoist as its hoisting mechanism, the QD series employs an independent trolley hoist—the hoisting mechanism, trolley travel mechanism, and drum are integrated into a single trolley that traverses along the main girder rails. This design enables higher lifting capacities and a longer service life. The main girders feature a box section or truss-type structure (large-tonnage models predominantly use box section), fabricated from welded steel plates, offering high bending stiffness and excellent load-bearing capacity.
The operator cabin is typically suspended beneath one end of the main girder, allowing the operator to control the crane manually or via remote control. The QD series can be configured with an operator cabin, remote control, or both, accommodating different operating preferences across various working conditions.
Technical Parameters and Price Reference by Tonnage
The standard lifting capacity range for the QD-type double-girder bridge crane is 5 t, 10 t, 16 t, 20 t, 32 t, 50 t, 75 t, 100 t, 150 t, 200 t, and 320 t. The table below lists the primary parameters and market reference prices for commonly used tonnages. Actual pricing is subject to variations in span, lifting height, work duty classification, and non-standard configurations—final quotations should be obtained from manufacturers.
| Model | Lifting Capacity(t) | Span(m) | Lifting Height(m) | Work Duty / Classification | price reference(10k CNY) |
|---|---|---|---|---|---|
| QD5 | 5 | 10~28 | 12~20 | A5~A6 | 10~18 |
| QD10 | 10 | 10~31 | 12~24 | A5~A6 | 15~25 |
| QD20 | 20 | 10~31 | 12~24 | A5~A7 | 20~35 |
| QD32 | 32 | 13~31 | 12~24 | A5~A7 | 30~50 |
| QD50 | 50 | 13~35 | 16~30 | A6~A8 | 50~80 |
Note: The prices above reflect the 2025–2026 market reference range. A 5t-class unit starts at approximately $14,800, while a 50t-class unit starts at around $74,200. For large-tonnage QD-type cranes above 100t, pricing typically falls between $118,600 and $222,500. Units rated at 200t or higher require custom engineering based on facility conditions, with pricing assessed on a case-by-case basis. Kelude Heavy Industry offers non-standard customization services, including structural optimization for special spans, lifting heights, or work duty classifications.
Key Technical Features of QD-Type Cranes
What sets the QD-type double-girder bridge crane apart from light and small lifting equipment comes down to three core technical advantages:
Superior load-bearing capacity with twin girders. The twin main girder box structure delivers a significantly higher bending section modulus at the same span, enabling lifting capacities up to 320t. Stiffener plates inside the main girders prevent local buckling, making the crane well-suited for frequent start-stop cycles and heavy-duty operations.
Variable frequency speed control for smooth lifting. The hoisting mechanism uses variable-frequency drive (VVFD) technology, allowing the main hook to operate at infinitely adjustable speeds from 1 to 10 m/min. Long travel speed ranges from 20 to 90 m/min, while cross-travel speed spans 10 to 45 m/min. VFD control minimizes inrush current during startup, reduces load swing, and extends the service life of both mechanical and electrical components.
PLC-based control system. Most QD-type cranes come equipped with a programmable logic controller (PLC) that integrates overload limiting, travel limit switches, emergency braking, and multi-mechanism interlocking for enhanced safety and automation. When paired with the VFD, parameters such as brake application delay and anti-load-slipping can be configured to further improve operational safety.
Application Scenarios and Selection Recommendations
The QD-type double-girder bridge crane is well-suited for the following typical applications:
- Metallurgy workshops: Handling of high-temperature heavy loads such as steel billets, steel coils, and ingots. Work duty classification of A7~A8 is required, and thermal insulation protection plus high-temperature cables are recommended.
- Machinery manufacturing plants: Transfer of dies, large machined parts, and assembly components. Standard spans (16–28 m) are typically sufficient, with A5~A6 work duty options available.
- Hydroelectric and pumping stations: Installation and maintenance of large equipment such as hydraulic turbines and generators. Lifting capacities typically range from 50 to 200t, with high demands on slow-speed positioning accuracy.
- Warehousing and logistics centers: Loading/unloading of heavy steel sections, large pipes, and containerized cargo. Remote control operation is recommended to boost handling efficiency.
- Shipbuilding and ports: Hoisting of hull sections and main engines, often requiring non-standard customization due to special span and lifting height requirements.
Selection key points: First, determine the maximum weight of the load to be lifted and add a 10%–20% safety margin. Next, measure the factory bay width (column center distance) and subtract the safety clearance to establish the crane span. Then, select the work duty classification based on operating frequency—2–4 hours per day calls for A5, 4–8 hours for A6~A7, and continuous heavy-duty 24-hour operation for A8. Lifting height should account for the spreader height, the load height, and the required safety clearance combined.
Special Equipment Management and Inspection Intervals
Under the Special Equipment Safety Law and TSG 51-2023 Crane Safety Technical Supervision Regulation, bridge cranes with a lifting capacity of 3t or above fall under special equipment supervision. All QD-type models (5t and above) must complete use registration and undergo periodic inspections.
Inspection interval requirements:
- Annual inspection: In-service bridge cranes must undergo a periodic inspection once every year.
- Biennial inspection: Cranes that have been out of service for more than one year before being recommissioned, cranes that have undergone retrofitting or major overhaul, and cranes involved in accidents must pass an inspection before being put back into operation.
- Monthly self-checks: The user unit must conduct and document monthly inspections of safety accessories, brakes, wire ropes, hooks, and other critical components.
When Kelude Heavy Industry delivers a QD-type double-girder bridge crane, the following documents are provided with the equipment: Type Test Certificate of Conformity, supervision inspection report, and operation and maintenance manual. The crane may only be put into operation after the user unit has obtained the use registration certificate from the local special equipment safety supervision authority.
Quick Data Overview
5–320t
Lifting Capacity Range
10–35 m
Span Range
From $14,800
Starting Price
≥3t
Special Equipment Threshold
A5~A8
Work Duty Classification
Indoor / Outdoor
Application Scenarios
The QD-type double-girder bridge crane product line from Kelude Heavy Industry covers the full range from 5t to 320t, supporting both rapid delivery of standard models and non-standard customization. For accurate tonnage quotations and selection recommendations, refer to the Bridge Crane Technical Encyclopedia for technical principles and structural details, or browse the Complete Guide to Non-Standard Crane Customization for the evaluation process of custom solutions. For electrical control system options, see Crane Electrical Control System Design for configuration guidance on VFDs, PLCs, and safety circuits.
FAQ
Q: What is the difference between the QD-type and the LH-type electric hoist double-girder bridge crane?
A: The QD type uses a separate trolley hoist with a hoisting mechanism consisting of an electric motor, gearbox, and drum assembly, offering higher structural strength and a longer service life, with a lifting capacity of up to 320t and a work duty of up to A8. The LH type uses an electric hoist as the lifting mechanism, featuring a relatively lightweight design and a lifting capacity typically not exceeding 32t, with a work duty of A3 to A5. For applications requiring more than 4 hours of daily operation or lifting capacities above 20t, the QD type is the recommended choice.
Q: Does the QD double-girder bridge crane require a foundation or embedded parts?
A: Yes. The bridge runway rails of the QD crane are installed on the crane runway girders of the factory building, which are typically connected to the building columns via embedded parts or corbels. For new factory buildings, embedded parts for rail installation should be reserved during the civil construction phase. For retrofit projects, the load-bearing capacity of the existing crane runway girders must be assessed to ensure they can accommodate the wheel loads of the new crane. It is recommended that the manufacturer provide wheel load data during the selection stage for verification by the design institute.
Q: Is an operator cab still necessary for remote-controlled QD cranes?
A: It depends on the operating conditions. A fully remote-controlled configuration can eliminate the need for an operator cab, reducing equipment costs by approximately $3,000 to $6,000, and is suitable for applications with unobstructed visibility and clear travel paths. However, for applications such as metallurgy or hydroelectric power stations that require precise positioning, or where the suspended load obstructs visibility during travel, retaining the operator cab is safer and more efficient. Kelude supports a dual-mode configuration with both remote control and operator cab, allowing operators to switch flexibly between the two.
Q: What is the typical service life of a QD crane?
A: Under normal operating conditions with regular maintenance, the design service life of a QD double-girder bridge crane is typically 20 to 30 years. Key factors affecting longevity include whether the actual work duty matches the design classification, the consistency of lubrication and wire rope inspections, and the timely replacement of aging electrical components. Once the design life is reached, a safety assessment is required to determine whether the crane can continue in service, be derated, or be scrapped.
