Anticorrosion work on mechanical seal is very important today to share some of the non Huibang metal ring anti-corrosion knowledge:
1, graphite ring corrosion. The company said in the information network with resin impregnated impermeable graphite ring, there are three reasons: one is its corrosion when the face of overheating, the temperature is higher than 180oC, the resin impregnated graphite ring to be folded away, the ring wear resistance decreased; two is the impregnating resin if the selection is wrong, so the seal cooling system set up, this is mainly the formation of fault material. The corrosion film, the film usually has the characteristics of maintenance effect, but the metal seal ring used in materials such as stainless steel, cobalt, passivation film, chromium alloy on the surface damage at the end face friction, in the new film under hypoxic conditions is difficult to generate, selection of resistant impregnating resin, selected for high pressure impregnation. Add the dipping depth is very necessary.
2, Shi Mohuan oxidation. In the oxidizing medium, in the face of friction or poor cooling, attack 350 ~ 40o DEG C temperature can make the graphite ring and the oxygen react, attack CO, gas, the surface became rough, and even break. Non metallic ring in the chemical medium and stress together under the effect, will break.
3, polytetrafluoroethylene (PTFE gasket) corrosion seal ring. Will in the medium have a chemical change, the wear resistance decreased; three is the depth of resin impregnation can stand when the impregnated layer, the wear resistance decreased. F4 filler such as glass fiber, the first episode of cracks in the thin area, and to develop in depth, attack break, crack sealing ring is usually radially divergent, so one or more. Graphite powder, metal powder and so on to improve its temperature resistance, wear resistance. The corrosion of F4 ring is mainly refers to the selective corrosion, dissolution or disintegration of the filling. Such as hydrofluoric acid, the hot corrosion of glass fiber elements, so it should be filled according to the concrete circumstances.