The surface of the Gland Packing work principle is very uneven under micro, and it can only be partially fitted with the root root. So there is a small gap between the plate root and the axis, just like a maze. The medium is intercepted multiple times in the maze, thereby achieving a sealing effect.
The filler seal is packed in the filler letter, and the filler is pressed tightly on the surface of the shaft through the filler cover. Because the axis surface is always rough, it can only be partially fitted with the filler, and part of it is not touched, which forms countless maze. When the band pressure medium passes through the axis surface, the medium is repeatedly cherished, reaching the seal with this "maze effect". The fit and friction between the filler and the surface of the axis are similar to sliding bearings. It should have sufficient liquid to lubricate to ensure that the seal has a certain life, that is, the so -called "bearing effect". This shows that good fillers are sealing, which is the synthesis of maze effects and bearing effects.
The compression of the filling of the shaft is generated by tightening the cover of the cover. Because the filler is a bullet -plastic body, when the axial pressure is tightened, the friction causes the compressor to gradually decrease along the axial direction. At the same time, the radial pressure generated by the generated is clinging to the surface surface to prevent the medium from leaking. The distribution of radial pressure tightening is from the outer end (cover) to the inner end. Leak from less than zero.
With the continuous emergence of new materials, the structural type of the filling has also changed a lot, which will undoubtedly promote the application of the filler sealing more widely. The materials used for fillers should have the following characteristics: there is a certain elasticity. When the filling is tightened by the axial pressure, a large radial pressure can be generated to obtain the seal; when the machine and shaft have vibration or axis beating and eccentric, they can have a certain compensation capacity (follow -up); chemical stability stability can be stable; sex. It is neither corrosive, soluble, nor polluting the medium; non -permeability. The medium has some penetration to most fibers, so the filler tissue is required to be dense. For this reason, it often needs to be impregnated, filling various lubricants and filling agents when making fillers; Essence After friction, it can withstand a certain temperature; easy to disassemble; simple manufacturing and low price.