Rational use and failure analysis of piston pumps

Piston pump is an important component in the hydraulic system, especially in metallurgical equipment, most of the energy components of the hydraulic system are piston pumps. It is very important to use the piston pump correctly and reasonably, master the fault diagnosis method of the piston pump and quickly eliminate the measures and means. Metallurgical hydraulic equipment is a large-scale automatic production line, and the components are faulty, which must be eliminated quickly to ensure the normal and stable production.

Selection principle
(1) The structure of the pump
When choosing the structure of a piston pump, the first thing to consider is whether it should be used in an open or closed system. If used in an open system, a swash plate pump without an auxiliary pump can be selected; Pumps and motors with auxiliary pumps and closed system integrated valves are also available if the variable mechanism or hydraulic valves and other auxiliary mechanisms are to be operated.
(2) Parameters of the pump
The basic parameters of the piston pump are pressure, displacement, speed, etc., generally according to the working pressure of the hydraulic system to choose the rated pressure of the pump, in metallurgical equipment, the normal working pressure of the hydraulic system can be selected as 70%~80% of the rated pressure of the pump, in order to ensure that the pump has enough service life. When selecting the parameters of the pump, the common working parameters of the host should be within the range of the high-efficiency area parameters of the pump efficiency curve. For pumps for indoor use, pay attention to choosing a low-noise pump.
(3) Service life
Service life is the sum of the pump's operating time under rated conditions during the overhaul interval. Metallurgical pumps require an overhaul interval of more than 5000 h.

Installation points
(1) Avoid radial force on the transmission shaft of the pump
Whether it is a non-shaft swash plate axial pump or a through-shaft swash plate axial pump, the transmission shaft is very sensitive to the radial force, therefore, it is not allowed to directly install the belt wheel, gear and sprocket at the end of the transmission shaft of the pump (motor), and special attention must be paid to check the coaxiality of the output shaft of the prime mover and the pump transmission shaft during installation, so as not to cause the wedge-shaped gap between the cylinder block and the distribution plate due to the bending of the transmission shaft, increase the leakage, reduce the volumetric efficiency of the pump, aggravate the wear between the cylinder block and the distribution plate, and seriously affect the service life of the pump.