During the process of using the hydraulic system, the l […]
During the process of using the hydraulic system, the liquid has a certain viscosity, so that when the product flows in the pipeline, its inevitable friction occurs, so the liquid in the hydraulic system must consume a part of the energy during the flow. This part of the energy loss is mainly reflected in the loss of pressure.
The pressure loss of the hydraulic system will be effectively along its loss and local loss. The loss of the equipment is the pressure generated by the friction when the liquid flows through a straight pipe with a constant diameter.
The local loss in the hydraulic system is directly caused by the sudden change of the section shape of the pipeline and the change of the direction of flow. The pressure resistance of other types of products will directly cause the pressure loss. The total pressure loss is equal to the sum of the loss along the path and the local loss.
Because the pressure loss in the hydraulic system is inevitably present, the rated pressure of the pump during operation is greater than the maximum working pressure required when the system is working. Generally, the maximum working pressure required for the system work is multiplied by a 1.3~1.5. The coefficients are estimated.
In a hydraulic system, each pressed element will have a relatively moving surface, such as the inner surface of the cylinder and the outer surface of the piston, because there must be relative movement between them, so there will be a certain gap between them, if one side of the gap is High-pressure oil and low-pressure oil on the other side will cause high-pressure oil to flow through the gap to the low pressure area and cause leakage.
The loss of flow in the hydraulic system affects the speed of movement, and the leakage situation is also difficult to absolutely avoid, so the rated flow of the pump in the hydraulic system is slightly larger than the maximum flow required for the system to work.