How to choose End Carriage

I. Main Functions

1. Supporting the Main Beam and Load: As the "two legs" of the bridge frame, it directly bears all vertical loads transmitted from the main beam (including the crane's own weight and lifting weight) and transfers them to the wheels and rails.
2. Installing the Traveling Mechanism: It serves as the mounting base for the trolley traveling mechanism. Driven and driven wheel sets are installed below both ends of the end carriage, driving the crane to move longitudinally along the rails in the crane building.
3. Ensuring Span and Stability: It precisely maintains the distance between the rails on both sides of the crane (i.e., the span) and ensures the overall stability of the crane during operation through its structural rigidity.

II. Typical Structure

A complete end carriage typically includes the following core components:

1. End Carriage: The main structure, mostly a box-shaped structure (a closed rectangular cross-section welded from steel plates), possessing advantages such as high strength, high rigidity, and good torsional resistance.
2. Wheelset Mounting Seat: A precision-machined bearing seat or mounting surface used to mount wheels, bearing housings, etc. Mounting accuracy directly affects the parallelism and diagonal difference of the wheels.
3. Connecting Flange or Panel: The part connecting to the main beam, fastened to the end flange of the main beam with high-strength bolts.
4. 

III. Motor Types

• Three-in-one motor: Suitable for open-gear end carriages;
• SEW motor: Suitable for European-style end carriages;
• Kone motor: Suitable for European-style end carriages
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IV. Design and Manufacturing Considerations

1. Materials: Usually Q235B or Q345B structural steel is used, requiring good weldability and toughness.
2. Structural Stiffness and Strength: Must be able to withstand maximum wheel pressure, inertial force, wind load (outdoors), and possible lateral forces during skewed operation.
3. Machining Accuracy:
1. Wheel reference surface distance (span direction): Must be strictly controlled to ensure the crane span meets standards.
2. Wheel perpendicularity and parallelism: To prevent "rail biting" (friction between the wheel flange and the side of the rail).
4. Welding process: All welds, especially load-bearing welds, must ensure full penetration and undergo non-destructive testing (such as ultrasonic testing) to prevent cracking.
5. Corrosion protection: After sandblasting to remove rust, apply high-quality anti-rust paint and topcoat. Outdoor cranes require even higher standards.