The Benchmark for General-Purpose Lifting: A Complete Analysis of Shandong Xingyuan Machinery's QD Type Double-Girder Overhead Crane

In industrial production, reliable and efficient material handling equipment serves as the core backbone ensuring the smooth operation of the production process. As a nationally recognized high-tech enterprise and a holder of the National Class A Special Equipment Manufacturing License, Shandong Xingyuan Machinery Co., Ltd. (hereinafter referred to as "Xingyuan Machinery") has been deeply engaged in the crane manufacturing field for nearly two decades. The company has meticulously crafted the QD type electric double-girder overhead crane—its most widely used and technologically mature "flagship product" within the product line. It is a reliable choice for material loading/unloading, handling, and equipment installation and maintenance within fixed spans in various industrial and mining enterprises, workshops, warehouses, stockyards, power stations, and similar facilities.

Product Definition: The "All-Rounder" in the Field of General-Purpose Lifting

The QD type electric double-girder overhead crane is the most widely used general-purpose lifting equipment manufactured by Xingyuan Machinery. This product strictly complies with the GB/T 3811 Design Rules for Cranes and GB14405 General-Purpose Overhead Crane standards. The complete machine features a novel structure, aesthetically pleasing appearance, excellent manufacturability, flexible and smooth operation, and outstanding safety and reliability.

Core Positioning:

In simple terms: if specialized cranes are the "special forces," then the QD type is the "all-purpose main force." It does not pick its working conditions or materials—it is the most trustworthy "all-purpose handler" in the industrial workshop.

Core Advantages: Five Highlights Forging the Benchmark for General-Purpose Lifting

2.1 Complete Series Lifting Capacity Coverage: One-Stop Configuration from 5 Tons to 500 Tons

Xingyuan Machinery's QD type double-girder overhead crane features a complete product series, meeting full-scenario lifting demands from small workpieces to giant equipment:

Special Note: Our company can carry out non-standard customized design according to customer requirements, ensuring that every QD type crane precisely matches the user's actual working condition needs.

High-Strength Box-Section Bridge Structure: The Stable and Reliable "Steel Backbone"

The bridge structure of the QD type crane is the core guarantee of its load-bearing capacity:

Main Girder Design:

Adopts a box-section main girder structure, precisely cut on a large CNC blanking line; the main web plate is cut with a preset camber curve to ensure the main girder remains level under full load.

Main welds are executed using automatic submerged arc welding, producing smooth and robust welds that undergo 100% ultrasonic flaw detection.

Main girder steel plate material is Q235B or Q345B, selectable according to different working condition requirements.

End Carriage Design:

The main girder and end carriages are connected with Grade 10.9 high-strength bolts, facilitating transportation and installation.

The end carriages adopt an articulated structure, making the overall crane operation more stable and reliable.

Both ends are equipped with anti-derailment devices and buffers.

 Three-in-One Traveling Mechanism: Smooth Start/Stop, Precise Positioning

Bridge Traveling Mechanism:

Enables the longitudinal movement of the crane along the plant rails.

Adopts a four-corner drive configuration for smooth starting and stopping with minimal impact.

Equipped with a variable frequency speed control system, achieving soft start and soft stop, smooth operation, and impact-free starting/stopping.

Bridge speed is adjustable within the range of 20–50 m/min according to requirements.

Trolley Traveling Mechanism:

The trolley moves laterally along the main girder rails.

Trolley speed is adjustable within the range of 20–40 m/min.

The trolley frame is of welded steel plate construction, compact and robust.

Wheel assemblies adopt a double-flange design to prevent derailment.

 Modular Hoisting Mechanism: Efficient Lifting, Safety Redundancy

The hoisting mechanism is the core working component of the QD type crane, consisting of an electric motor, reducer, drum, and hook assembly, responsible for the vertical lifting and lowering of materials.

Technical Parameters:

Main hoisting speed is adjustable within the range of 0.4–15.5 m/min depending on the tonnage.

Heavy load slow speed, light load fast speed, ensuring both safety and efficiency.

Optional dual brake configuration provides safety redundancy.

Safety Configurations:

Overload limiter: Real-time monitoring of the lifted load; automatic alarm activation and hoisting circuit cutoff in the event of overload.

Upper and lower limit switches: Dual limit protection to prevent hook over-lifting.

Overspeed switch: Prevents loss of control of the hoisting mechanism.

 Intelligent Electrical Control System: Precise Coordination, Convenient Operation

The QD type crane comes standard with a PLC programmable controller + AC variable frequency drive system, enabling precise and coordinated movements of all mechanisms.

Three Operation Methods:

 

 

Operation Method	Applicable Scenarios	Advantages
Cabin Operation	All-weather, high-intensity tasks	Wide field of view, comfortable operation, reduced fatigue
Wireless Remote Control	Flexible tasks, close-range precise alignment	Operator can move freely, optimal field of view
Ground Pendant Operation	Simple tasks, intermittent use	Low cost, intuitive operation

Structural Composition: Four Major Modules Working in Coordination

The QD type double-girder overhead crane consists of four core components, with all modules working in coordination to complete the entire operation process from material pickup to discharge:

Bridge Metal Structure

Adopts a box-section double main girder structure, welded using automatic submerged arc welding.

The main girder and end carriages are connected with high-strength bolts.

The main girder features high rigidity and strong bending resistance.

Each bridge structure is assembled and tested in the factory to ensure the running rails are level.

 Bridge Traveling Mechanism

Enables the longitudinal movement of the crane along the plant rails.

Four-corner drive with a "three-in-one" drive unit.

Variable frequency speed control for smooth operation.

 Lifting Trolley

The trolley frame is of welded steel plate construction, compact and robust.

Contains the hoisting mechanism and the trolley traveling mechanism.

The trolley travel uses a "three-in-one" drive.

The trolley power supply uses an I-beam rail + cable conductor system.

 Electrical Control System

Adopts a PLC programmable controller + variable frequency speed control.

Safety monitoring system: Overload limiter, limit switches, emergency stop.

Centralized cabin control with a wide field of view.

V. Applicable Scenarios: Ubiquitous