Structural features of hydraulic transmission concrete pump

A concrete pump is a machine that uses pressure to continuously transport concrete along a pipeline. Consists of a pump body and a delivery tube. According to the structure, it can be divided into piston type, extrusion type and hydraulic diaphragm type. The pump body is mounted on the chassis of the vehicle and equipped with a retractable or inflected boom to form a pump truck.

The hydraulic transmission type concrete pump is composed of a hopper, a hydraulic cylinder and a piston, a concrete cylinder, a distribution valve, a Y-shaped pipe, a flushing device, a hydraulic system and a power system. The hydraulic system pushes the piston back and forth by pressure. The material is sucked when the piston is moved backwards, and the Y-shaped tube is used to push the concrete in the concrete cylinder into the conveying pipe. After pumping concrete, clean the pump body and delivery pipe with high pressure water or compressed air. The displacement of the piston concrete pump depends on the number and diameter of the concrete cylinder, the reciprocating speed of the piston and the volumetric efficiency of the concrete cylinder suction.

The hydraulic system of the concrete pump truck is mainly composed of hydraulic pumps, hydraulic motors, hydraulic cylinders, accumulators, filters, coolers, valves, pressure gauges, oil pipes and fuel tanks. It is generally divided into four subsystems: the main hydraulic system of the pump truck, Boom legs and turret hydraulic system, pump truck's mixing and cooling hydraulic system and washing hydraulic system. In order to reduce the weight of the hydraulic components such as hydraulic cylinders on the distribution poles, the distribution pole and the leg circuit use a higher rated pressure. The hydraulic system of the pump truck varies depending on the model, but its basic working principle is the same. In concrete pump hydraulic systems, due to performance requirements, the system is often equipped with safety valves, relief valves and sequence valves. If the pressure of the safety valve is adjusted too low, the safety valve will be frequently opened, resulting in overflow loss, resulting in system heating; if the pressure is adjusted too high, it will increase the leakage within the system, so that the system heat, therefore, should press the hydraulic system Load requirements, correct calculation and adjustment of safety valves and pressure values ​​to ensure that the system works within the specified pressure range. When the main circuit of the concrete pumping pumping system is a closed system, a heat exchange circuit must be provided in the pumping system. The set pressure of the overflow valve in the heat exchange circuit should be taken seriously, and the set pressure is too low, which will cause pumping. The hydraulic cylinder commutation shock increases, setting the pressure too high will make the overflow loss too large and the system temperature rise too high. If the adjustment pressure of the internal control type sequence valve is too high, when the working pressure of the working hydraulic cylinder is lower than the adjustment pressure, there is a pressure loss at the valve port of the sequence valve, causing temperature rise, causing system heating and reasonably determining the setting of the internal control type sequence valve. The pressure can make the working pressure of the working cylinder higher than the opening pressure of the sequence valve. When the sequence valve is working, the valve port will be fully opened and there will be no pressure loss at the valve port, thus avoiding the system heating caused by improper setting pressure of the sequence valve. .