sliding seal

Mason also developed a sliding seal for the exhaust from the moving cylinder saddle into the smoke box.

There are no rolling bearings or sliding seals, thus there is very little friction or wear.

Benefits include no significant moving parts, no sliding seals, no lubrication, environmentally safe working fluid, and continuous capacity control.

Unlike a centerboard or daggerboard trunk, the opening for a canting keel must allow significant lateral motion, which requires sliding seals.

Experiments have shown that the jointing forces for HepLockô sliding seals are similar to those of rolling rings when all other factors are equal.

Several such setups require rotary or sliding seals, which can introduce difficult tradeoffs between frictional losses and refrigerant leakage.

For these reasons, designers prefer non-lubricated, low-coefficient of friction materials (such as rulon or graphite), with low normal forces on the moving parts, especially for sliding seals.

Vane actuators require a number of sliding seals and the joins between these seals have tended to cause more problems with leakage than for the piston and cylinder type.

However, a disadvantage of this machine is that one connecting rod must have a sliding seal at the hot side of the engine, which is a difficult task when dealing with high pressures and high temperatures.

At a high enough pressure the sliding seals between cavities will leak some fluid rather than pumping it, so when pumping against high pressures a longer pump with more cavities is more effective, since each seal has only to deal with the pressure difference between adjacent cavities.