Low wear, high pressure shaft seal
A radial shaft seal has been developed that remains stable under pressure in dynamic applications up to 10 bar and is capable of withstanding pressure peaks of up to 30 bar, with a bursting strength of 100 bar
. The makers of the seal, Simrit, say it's ideal for hydrostatic drives in agricultural machinery such as hydraulic engines and hydraulic pumps.
Flange bores in housings that are subject to high pressure require special seals. With conventional pressure seals, an internal pressure of no more than 2 bar can lead to considerable wear on both the seal and the shaft. Simrit’s Premium Pressure Seal (PPS) 'Simmerring' was developed to ensure that shafts in hydrostatic drives are reliably sealed in these applications. Its patented sealing edge, which was designed to withstand high internal pressure, prevents the formation of damaging hollow grooves.
The very short, flexible, suspended spring-loaded sealing lip can reduce the wear width of the sealing edge to less than 50% of the normal width. And, the lip’s force of pressure increases only slightly as the internal pressure rises. This minimises friction torque significantly even under high operating pressure and minimises both thermal load and wear.
Simmerring is made of wear-resistant elastomer and can be used at the sealing edge for operating temperatures of up to 160°C. Optional special materials are available for special applications such as those with heavily pulsating internal pressure levels.
The seal requires no back-up ring for the sealing edge which simplifies assembly. And nubs on the front face prevent rotary shaft seals that are mounted on top of one another from sticking together, thereby paving the way for the automatic installation of these seals in series production. The seals are also available in cassette form for permanent and reliable sealing of axles in agricultural machines. DP
Pointers
* The very short, flexible, suspended spring-loaded sealing lip can reduce the wear width of the sealing edge to less than 50% of the normal width
* The seal requires no back-up ring for the sealing edge which simplifies assembly
* Nubs on the front face prevent rotary shaft seals that are mounted on top of one another from sticking together
