How is a single-beam bridge crane inspected on a daily basis

The routine inspection of single-beam bridge cranes is a crucial step to ensure the safe operation of the equipment and prevent malfunctions. The inspection should cover four core areas: mechanical structure, electrical system, safety devices, and operational performance. It should incorporate methods such as visual inspection, manual operation, and instrument testing to form a standardized process. The following are the specific inspection steps and key points:

1. Mechanical structure inspection: ensure structural integrity

Main beam and end beam

Visual inspection: Observe whether the main beam and end beam exhibit deformation, cracks, or welding defects. Emphasis should be placed on inspecting the mid-span area (where the main beam experiences the greatest stress) and the welds at the connections.

Measuring tool: Use a laser range finder or a level meter to detect the camber of the main beam (the standard value is usually 1/1000 to 1.4/1000 of the span). If the camber disappears or the deflection exceeds 1/700 of the span, it should be immediately stopped and repaired.

Fastener inspection: Inspect whether connectors such as high-strength bolts and pin shafts are loose, and use a torque wrench to verify whether the bolt preload meets the design requirements (e.g., the preload of an M24 bolt is typically 300~400N·m).

Wheel set

Wheel flange wear: Measure the thickness of the wheel flange with a caliper. If the wear exceeds 50% of the original thickness (for example, if the original thickness of the wheel flange is 30mm and it is ≤15mm after wear), the wheel needs to be replaced.

Tread wear: Check whether the wheel tread is flat. If there are pits or peeling, it needs to be polished or replaced.

Parallelism adjustment: Use a dial gauge to measure the deflection of the wheel set in both horizontal and vertical directions, ensuring that the deflection does not exceed 1/1000 of the measured length.

Track (or railway)

Straightness inspection: The straightness of the track shall be inspected using the steel wire method or a laser straightness instrument, with an error limit of ≤3mm (over the full travel distance).

Joint gap: Check whether the track joint gap is 1~2mm, and the height difference is ≤1mm. Otherwise, it is necessary to adjust or replace the track pad.

Fixing bolts: Confirm whether the track pressing plate and bolts are loose, and use the hammering method to listen to the sound to judge the tightening status of the bolts.