What is the purpose of backup ring?
Back-up Rings are flat, split, spiral or contoured washer type fittings used to protect an O-Ring seal from extrusion at higher pressures and temperatures. A Back-up Ring works by blocking or reducing the extrusion gap, thus preventing the o-ring from extruding.
When would you use a backup ring?
Backup rings are used for both static and dynamic fluid power applications and prevent the migration or extrusion of an O-ring in the gap as pressurization and de-pressurization/pressure cycling occur.
How do backup rings work?
Back-up rings, or anti-extrusion rings, are thin rings that are designed to prevent O-ring extrusion under pressure. They fit in the gland between the seal and the clearance gaps to provide zero clearance. Read on to find out more about the function of these invaluable parts.
Why are backup rings sometimes used with O rings?
Backup rings are ultimately used to help stop o ring migration, and they achieve this in both static and dynamic fluid power applications as the pressure cycles occur, preventing the extrusion of an o ring in the gap.
What is the use of backup ring with seal in hydraulic system?
The primary purpose of the back up ring is to reduce the extrusion gap between metal surfaces of two cylinder components to enable the seal to operate at higher pressures without extruding and being damaged.
Which side does the backup ring go on?
If you are installing a backup ring, a good tip is to make sure it is installed on the low pressure side of the system, that way the high pressure side of the system pushes the O-ring against the backup ring.
Which side of an O-ring does the backup ring go?
What is the use of back up ring with seal in hydraulic system?
What is the purpose of a Teflon backup ring when used with an O-ring?
Teflon back-up rings are designed to prevent extrusion in rubber o-ring sealing systems. Rubber O-Rings generally serve as effective seals for dynamic and static applications in hydraulic and pneumatic systems equipment.
Should O-rings be lubricated?
Lubricating an O-ring is an important part of the assembly line process as it can help protect an application from abrasion or scuffing damage. The addition of a lubricant can extend the operating life of the O-ring by creating a barrier film over its surface.
When do you use a back up ring?
Back-up rings are washer-like devices that are used to prevent a seal from extruding through any gaps while under pressure. These seals are installed in the downstream side of the gland. Back-up rings are not seals themselves, but are usually used in conjunction with O-rings in high-pressure applications (over 1500 psi) for support or as spacers.
What do back up rings do in a pressure gland?
Description. Back-up rings are washer-like devices that are used to prevent a seal from extruding through any gaps while under pressure. These seals are installed in the downstream side of the gland. Back-up rings are not seals themselves, but are usually used in conjunction with O-rings in high-pressure applications (over 1500 psi)…
Why is a back up ring called a parback?
This concave style was made popular by Parker Seal Co. and is commonly called a Parback. The theory behind the concave style is that the curvature of the back up deflects the O-Ring away from the extrusion gap as system pressure deforms the O-Ring against the back up ring.
When to use a back up ring on a durometer?
In the case of a 70A durometer O-Ring, a back up ring should be used at pressures exceeding 1500 PSI – depending on extrusion gap, temperature, speed and other factors. Back up rings used with O-Rings are of two different shapes.