New seals leak and cause analysis

Sometimes mechanical seal leakage , not due to leakage caused by face , but because ring, stationary ring seal or sleeve seal leak caused . For the following reasons :
Machine rubber seals leak
Actuating ring, stationary ring "O" type rubber seals, rubber finish is not enough because the hardness inappropriate , good elasticity , friction coefficient, geometry failure , heat resistance, corrosion resistance and other good reasons, often cause seal leakage .
Machine shaft seal ring in contact with leaking
When a sleeve repeated use in contact with ring seal and sleeve at the sleeve surface will have a rough grinding marks and spots , often caused by seal leakage . The main reasons are:
( 1) Since the rail car seals ring and the sleeve exists between the small amount of relative movement , or other hard abrasive grains embedded impurities into the softer seal . Produce a friction rub on the sleeve , and the sleeve surface without surface hardening treatment or processing of poor quality , resulting in wear and tear.
( 2 ) the result of friction rub , the metal surface passivation film sleeve damage present on the surface of the metal sleeve electrode potential difference , the formation of electrochemical corrosion. Also, because of the contact at the leak itself and in the micro crevice corrosion when they have the condition , therefore , the corrosion rate is higher . Furthermore , seal ring side in contact with the atmosphere , due to the presence of oxygen , more complex and harsh etching conditions , so wear marks and spots more obvious.
PTFE sealing ring group polytetramethylene used in the ring , due to the smaller coefficient of friction than the rubber , high finish , easy to move with the ring , thus , is better than the rubber seals . Rubber seals used in the stationary ring , due to good elasticity, low hardness, therefore , the reliability is better than the PTFE ring seal . Therefore, a reasonable choice of ring material is also very important, and we based on the specific circumstances of corrosion on the mechanical seal made ​​the following adjustments: the media side stationary ring with Teflon rings or rubber ring temperature corrosion in the atmosphere quiet side always use rubber ring ring ; ring PTFE seals are generally used , the effect is more ideal .
Bushings eliminate fretting , except try to use the sleeve surface hardness, good corrosion resistance, and maternal affinity, high surface finish of better spraying spraying materials and processes , but also pay attention when installing bushings wear, timely replacement of bushings, new security seals, in many ways to ensure sealing reliability.