Back up rings

STU-type backup rings are used in combination with radial-sealing O-rings to prevent gap extrusion (extrusion of seals into the sealing gap).
STU-type backup rings are endless elastomer rings with a concave cross-section, which provides the O-ring with a more extensive contact surface. This enables the O-ring to maintain its nearly round cross-section even under high pressure, and it is subject to very low deformation. This produces an improved sealing effect and increases the operating life of the seal. The STU backup ring has no sealing function itself. But its symmetrical profile allows it to be used in internal and external sealing systems.
A&S Seals Co., Ltd. is a global supplier of Back up rings, DICHTOMATIK Seals, A&S Seals and many more. focusing on the various brands of seals supply