The fact that the 7500 seal turns with the shaft is a major benefit for customers. Because rope packing is stationary and the shaft is turning through it, it can score and damages the shaft; which can lead to a big expense when you have to replace the shaft. With CinchSeal, the internal seal elements turn with the shaft and shaft damage is eliminated.
In the 7550 shaft seals series, the rotor cups are made from a special mineral filled PTFE blend, and are the wearable part of the seal. On the 7520 model the rotor cups are made out of aluminum that we hard coat with a special process that give them a hardness of a 62 on the Rockwell scale. (The same hardness as Tungsten Carbide) The hard coated aluminum rotor cups run against inner and outer PTFE stators, which are now the wearable part of the seal and will be replaced when worn.
When buying a repair kit for the 7550 model it would consist of a new solid elastomer and new PTFE rotor cups. If you have a 7520 model a repair kit consists of a new elastomer and two new PTFE stator plates. (See exploded views below) All these pieces compress into the seal as you tighten down the cover plate with the 4 screws and the optimum seal face load is established.
The newly rebuilt seal is bolted up to the machine where it will run for 1,000’s of hours providing leak-free service before a repair kit will be needed. Contact us for more information!