For the protection of specific components in the hydraulic system, installed in the pressure line upstream element to be protected, in order to filter out the working medium of solid particles and colloidal substances, effective control of pollution of the working medium, and components to work properly. Hydraulic oil filter mainly stainless steel wire mesh, sintered wire mesh, iron preparation network, as a material, due to the media it uses are mainly glass fiber filter paper, synthetic paper, wood pulp paper, so it has concentric rate, to withstand pressure , straight is good, stainless steel, without any glitches, to ensure long life characteristics, its configuration is made of a single layer or multi-layer metal mesh and filter, use it in the specific number of layers constituting the screen the mesh according to different conditions and uses.