What is the reason for the loud noise of A7VO variable plunger pump? The phenomenon of suction is one of the important reasons for the excessive noise of the variable piston pump. When the oil enters the air, it is easy to form cavitation signs in its high-pressure area and spread in the form of a pressure wave, causing the oil to oscillate and causing the system to produce negative cavitation noise. The main reasons are as follows: 1. The oil filter and the oil inlet pipe of the variable plunger pump are blocked or the oil viscosity is too high, which can cause the vacuum at the oil inlet of the pump to be too high and make the atmosphere penetrate. 2. The oil seal at the shaft end of the variable plunger pump and the pilot pump is damaged, or the oil inlet pipe is poorly sealed, causing atmosphere to enter. 3. The oil level of the oil tank is too low, so that the oil inlet pipe of the plunger pump is directly emptied. The reason for the loud sound of the A7VO variable plunger pump is introduced as above, and I hope it will help you in future use! If you are very interested in our products after reading, please pay attention to: www.rexroth-hyd.com, welcome to buy!