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The XA Polon® anti-extrusion ring (single turn continuous version) is used in combination with O-rings, preferably in static applications, to prevent gap extrusion. XA anti-extrusion rings are suitable for maximum pressure loads. They are intended for installation in axially open grooves.
Polon® anti-extrusion rings are available in three versions:
XA: Single turn continuous
XB: Single turn scarf cut
XC: Spiral cut
• Insensitive to pressure peaks.
• High extrusion resistance.
• Excellent media resistance in case of suitable compound selection.
• Suitable compounds available for special requirements of the chemical process industry.
• Suitable compounds available for special requirements of the food processing industry.
• Any desired nominal diameter available due to use of machining technique.
• Installation in closed and undercut housings.
We recommend to specify back-up rings when at least one of the following working conditions is present in cases where the intention is to seal with O-Rings only:
• Pressure above 70 bar.
• Diametral clearance exceeding 0.25 mm at p > 10 bar.
• High stroke frequency.
• High temperatures.
• Contaminated medium.
• Strong pressure pulsing or pressure changes.
