U Cup General Information Part ll

A u cup is more or less a floating seal that lets pressure to balance out on both lips, keeping it from rolling.  You can put in an internal lube in the u cups, so that when there is lack of lubrication or dry application. This will get to the seal and keep it lubricated.

You will need to let your supplier know what kinds of application you will use the seal for, as there are different fabrics for different seals.

Most surfaces for a seal will need to be 32 RMS max.  The varying surface needs to be between 8 to 16 RMS. If you have a coarser surface that is more than 16 RMS, it might cause your lip seal to wear down. And if you have a finer surface than 8 it could cause the application to fail due to lubrication.

Below is a packing space chart, if you need more info on these types of seal, call us at

800-361-0068

sales@hydrostatic-transmission.com