Analysis of the Causes of Pipe Blockage Faults in Concrete Pump Trucks

The causes of pipe blockage faults caused by concrete pump trucks:

A SY5360 type 45m pump truck operates normally in both forward and reverse pump acceleration, water pumping and mortar delivery, but it experiences pipe blockage when pumping concrete. It was observed that the concrete was always blocked at the third boom pipe during pumping, so it was suspected that there was a foreign object blocking the pump pipe.

(1) The third section of the pump pipe was disassembled for inspection, and no foreign objects were found inside. It was reinstalled, but the fault persisted during the test run.

(2) Turn the pump in the correct position and observe that the main system pressure is around 10 MPa, which is normal. At the same time, test the system pressure build-up, which can reach a maximum of 34 MPa. Therefore, the vehicle is a new one that has only been in use for three months, so the fault of the main pump hydraulic system can be ruled out.

(3) Stop the machine, relieve the pressure, disassemble the reducer pipe, check that there are no foreign objects in the S pipe, and at the same time inspect the piston head, which is normal and free of wear.

(4) Disassemble the elbow pipe at the third boom section, align the pump, and the concrete can be pumped. It is suspected that there are foreign objects in the pump pipe behind. After disassembly and inspection, no foreign objects were found.

(5) Analyze the pumping system. The pressure is normal. The piston in the conveying cylinder is normal and there is no foreign object in the S pipe. The fault should be determined to be in the pump pipe. After disassembling and inspecting all the pump pipes, it was found that a mixing blade of the mixer truck was horizontally stuck in the first section of the horizontal pipe at the walking platform. It was cut and removed with an acetylene flame, and then the pump pipe was reinstalled. During the test run for pumping, everything was normal.

The cause of the malfunction was the detachment of the blades inside the mixer.