X-rings (also known as quad rings or four-lobed seals) offer an alternative seal solution to O-rings for use in reciprocating dynamic or rotary applications. They are often used in applications where the seal is required to operate under lower pressure and temperature conditions. Under low pressure, high sealing efficiency can still be achieved with an X-ring as the mould parting line is not coincident with the primary sealing faces.
Visit the Precision Polymer Engineering Ltd (PPE Prepol) website for more information on X-rings