Concrete delivery pumps such as wet shotcreting machines are widely used by construction units. However, during construction operations, the main motor cannot reach the specified speed and the piston rod of the main cylinder crawls. Qingke Heavy Industry is specialized in the production of wet shotcreting machines and other concrete equipment. The manufacturer brings you the failure analysis and solution measures of the concrete pump.
If the main motor does not reach the specified speed, it may be due to improper operation or malfunction of the hydraulic system. Therefore, before starting the machine, make sure that the operating handles of the water pump and the mixing motor are in the neutral position, and the pumping button is turned off before starting the operation. If the fault still occurs, first check whether the power supply voltage and transformer capacity are normal. The transformer capacity is generally 1.15 times the calculated load, and then determine whether the power supply line meets the requirements through calculation and measurement of the voltage at the start, and ensure that the voltage drop is less than 5%. When the voltage drop is too large when starting, the wire diameter should be increased appropriately. If it still fails to start, check whether the solenoid valve that controls the pressure of the main oil pump is normal to ensure that the main oil pump is in a discharged state when starting.
In order to ensure reliability, the electrical components of the concrete pump are generally imported parts, which require high voltage. The generally used star-delta starting can provide a sufficiently high voltage, the power supply machine runs, and gradually reaches the specified speed, but when the star connection is converted to the delta connection, the power supply voltage will drop significantly, the contactor coil suction will be reduced, and At the moment of conversion, there will be a very short power-off time, which will cause the motor speed to drop. After the motor enters the running state (delta connection), the motor torque is small, which is not enough to overcome the required resistance to make the motor reach the specified speed. The contactor will be disconnected, the main motor will be powered off, and the motor will automatically stop. In this case, the motor can be started normally by appropriately increasing the wire diameter.
When the main oil pump produces noise and the main oil cylinder piston rod crawls, it may be because the main oil cylinder piston rod sealing ring is too tight, and the movement resistance of the piston rod increases after the oil temperature increases, which affects the movement of the piston. In addition, the loose installation of the main oil pump is not only a cause of noise, but also may make it easy for air to enter the hydraulic oil circuit, causing the piston rod of the main oil cylinder to crawl. Qingke Heavy Industry believes that we can check the above factors of concrete pumps one by one and take corresponding measures. If the seal ring of the piston rod of the main oil cylinder is too tight, replace the seal ring. If the hydraulic oil foams, replace the hydraulic oil in the oil tank. If the oil level of the oil tank is too low, add hydraulic oil to the oil tank.
