MG Double-Girder Gantry Crane: Tonnage, Price & Specs

The MG-type double-girder gantry crane is a workhorse in heavy industry, widely deployed in steel structure fabrication, shipbuilding, ports, rail freight yards, and hydraulic engineering projects that demand reliable heavy-load lifting. Unlike MH-type single-girder gantry cranes, the MG series features twin main girders, substantially boosting load-bearing capacity and establishing it as the standard solution for large-span, high-tonnage operating conditions. This article provides a systematic overview of the full MG series—covering model parameters, structural features, price ranges, and selection key points—to support informed purchasing decisions.

MG Series Model Parameters Comparison

MG-type double-girder gantry cranes are graded by lifting capacity and span. The table below outlines the technical parameters across the full tonnage range:

The parameters above cover the standard MG Type configuration. An MG Type double-girder gantry crane with a lifting capacity of 5t or more falls under special equipment supervision (lifting capacity ≥3t and lifting height ≥2m), requiring use registration and periodic inspection. Kelude's full range of MG Type double-girder gantry cranes comes standard with anti-rail-gnawing devices and overload limiters, and each unit ships with a Type Test Certificate.

Twin Main Girder Structural Features Compared

The MG Type double-girder gantry crane features two box-type main girders arranged in parallel, connected by end carriages to form an integrated frame. Unlike the MH Type single-girder design, the twin-main-girder configuration offers three key load-bearing advantages:

Higher load capacity: The twin-girder structure distributes the load across both main girders, so each girder experiences only half the bending moment of a single-girder design (assuming uniform stiffness). Twin girders also provide far superior torsional stiffness—a single girder twists under eccentric loads, whereas twin girders restrain each other, boosting torsional rigidity by roughly 3 to 5 times. At the same tonnage, the MG Type achieves a 15–25% lower main girder section height than the MH Type, making it a better fit for facilities with limited headroom.

Greater span flexibility: The MG Type covers standard spans from 10 to 40 m, while the MH Type single-girder design is typically limited to 7–30 m. Beyond 30 m, deflection and dead weight become difficult to control with a single girder, making the twin-girder configuration the only reliable option. For spans of 35 m and above, the MG Type can also be supplied with a truss-type main girder instead of a box section, cutting dead weight by 20–30%—though at some cost in stiffness and dustproof performance.

Outrigger structural design: The MG Type typically uses a rigid-leg/flexible-leg combination—one rigid leg (rigidly connected to the main girder to transmit horizontal forces) and one flexible leg (pin-connected to carry vertical forces only). This arrangement relieves additional stresses caused by thermal deformation and manufacturing tolerances. Kelude's MG Type comes standard with the rigid-leg plus flexible-leg configuration, and a dual-rigid-leg option is also available for small-span, high-precision positioning applications. The choice of outrigger configuration depends on span, rail gauge accuracy, and ambient temperature conditions.

MG Type vs. MH Type: A Selection Comparison

The MG Type and MH Type represent two distinct technical routes for gantry cranes. Choosing between them depends on lifting capacity, span, frequency of use, and budget. Here's a six-point comparison:

Selection Criteria: For operating conditions with a lifting capacity of ≤20t and a span of ≤30m, where usage frequency is low, the MH Type is the preferred choice for cost-effectiveness. For applications requiring a lifting capacity of ≥32t, a span of ≥30m, or a Work Duty classification of A6, the MG Type double-girder model is mandatory. Kelude offers the full range of both MH Type and MG Type gantry cranes. For detailed parameters of the MH Type single-girder gantry crane, refer to MH Type Single-Girder Gantry Crane Parameters and Pricing. For comprehensive knowledge on gantry crane selection across all models, see Gantry Crane Model Parameters, Pricing, and Selection Guide.

MG Type Double-Girder Gantry Crane Price by Tonnage

The following reference prices apply to MG Type double-girder gantry cranes configured with a box-type main girder, rigid/soft leg combination, standard span, and electric hoist lifting mechanism:

Pricing Note: The above prices are ex-works and include tax, but exclude freight and installation. Larger spans and additional configurations increase the price. Adding a cantilever on each side (5m per side) adds approximately USD 3,000–18,000, depending on the tonnage. Kelude offers a free selection and quotation service for MG-type double-girder gantry cranes. Based on your actual operating parameters (rated lifting capacity, span, lifting height, and work duty), we will provide a detailed technical solution and quotation.

Application Scenarios and Crane Selection Process

Steel Structure & Equipment Manufacturing: In steel fabrication workshops, bridge steel structure plants, and pressure vessel production facilities, the MG-type crane handles the lifting and transport of steel plates and large components. A typical configuration includes a 16–32t capacity, a 22–35m span, a A5 work duty, and a box-type main girder with a single hoist winch. These applications are primarily indoor operations with standard rail foundation requirements. For more details, refer to the section on rail foundations in our comprehensive gantry crane selection guide.

Shipbuilding & Ports: This includes shipyard block assembly shops, port container yards, and bulk cargo terminals. With lifting capacities ranging from 32t to 100t and above, these cranes often require dual winches or a main/auxiliary hook configuration. In shipbuilding, MG-type cranes are typically equipped with two trolleys (one with a main hook, one with an auxiliary hook), and feature spans and lifting heights greater than the standard. These outdoor applications demand robust anti-wind and anti-slip measures, such as rail clamps, rail wedges, and anchor devices.

Railway Freight Yards & Hydraulic Engineering: Used for container handling at railway freight yards, precast component hoisting in water conservancy projects, and large building material storage yards. With a 20–50t capacity and a 30–40m span, a truss-type main girder offers a more cost-effective solution in these scenarios. For outdoor use, pay close attention to the electrical system's waterproof and dustproof protection rating (IP54 and above).

The Four-Step Selection Process:

Step 1: Determine the lifting capacity and span. Calculate the rated lifting capacity by multiplying the weight of the heaviest load by a safety factor of 1.1. Determine the crane rail span by subtracting the required safety distance on each side from the factory building's width.

Step 2: Determine the work duty. Select the appropriate classification based on the frequency of use and the load spectrum (e.g., intermittent light load A4, frequent medium load A5, or continuous heavy load A6). The work duty directly influences the main girder's cross-section design and motor power.

Step 3: Choose the main girder type. For standard conditions, a box-type girder is preferred for its excellent stiffness and dust resistance. For large spans with light loads, a truss-type girder is more economical due to its lower dead weight and cost.

Step 4: Define the additional configurations. Decide whether you need a cantilever, a single winch or dual winches/main-auxiliary hooks, a remote control or an operator cab, and anti-wind and anti-slip devices.

Frequently Asked Questions (FAQ)