P Metric Dynamic Back-up Rings

The “P” series PTFE back-up rings are proven components used for sealing both low and high pressure systems specifically for dynamic applications. Any system pushing the pressure limits on an elastomer seal, “P” series back-up rings are an inexpensive option to increase seal pressure capabilities or increase radial extrusion gaps behind the seal.

The “P” series dynamic back-up rings come standard in T-LON® (Virgin PTFE) but can be made from any filled T-LON® PTFE compound or plastic/metal to increase the pressure capabilities.

Consider “P” series back-up rings with elastomer o-rings under the following conditions:

• Pressure above 1000psi (7MPa)
• Radial Extrusion gap > .005″ (.13mm)
• High Reciprocating Stroke Frequency
• High Temperatures
• Medium with Contamination
• Pressure Shock Loads (Fast Pressure Changes)

Advantages:

• Inexpensive option with the solid “T3” option
• Easy to install with the cut “T2” option
• Increase pressure rating of standard o-rings
• Available for cylinders up to 1100mm 01 diameter

Applications:

• Mobile Hydraulic Cylinders
• Pneumatic Piston Cylinders
• Agriculture Equipment
• Hydraulic Valves and Pumps
• Filling Machines
• Testing Machinery
• Any sealing application

Technical Data for PTFE compounds:

• Temperature Range: -240° to 260°C T-LON®
• T-LON® seal compound determines allowable pressure
• Pressure: Up to 40 MPa (Function of e-gap and T-LON® compound)
• Surface Speed: Up to 2 m/s

Most Common:

Virgin PTFE (“01”)

• Most cost effective
• Most flexible for fitting into tight areas

BRONZE FILLED PTFE (“21” or “22”)

• Highest Extrusion Resistance of PTFE < 2 0.08 0.05 0.03 Compounds (Higher bronze content increases extrusion/wear resistance; I.E. larger e-gap allowable)
• Low abrasion characteristics

Also Available for Extreme Pressures greater than 40MPa: PEEK Compounds (“91” or “92”) Polyamide Compounds (“1N” or “6N”) ACETAL (“1D”)

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