BS back-up ring BS

spiralPTFE

Product description The Back-up Ring BS features a spiral profile for easy assembly and compatibility with a wide range of groove designs. Under pressure the spiral support ring bears against the groove flank, preventing elastomeric seal extrusion. Back-up rings are turned from virgin PTFE and precisely matched to groove height; the groove width required increases by the ring width.

Fields of application

• static
• dynamic
• single acting
• double acting
• linear
• rotating
• oscillating

Main use Protective element for elastomeric sealants against gap extrusion in grooves and clearances

Materials PTFE (virgin), PTFE with filling materials (filled PTFE)

Technical values

• Pressure: static up to 250 MPa; linear up to 40 MPa; rotatory up to 5 MPa
• Temperature range: -200°C to +260°C (material dependent)
• Speed: linear up to 0.5 m/s; rotatory up to 2 m/s
• Material (summary): PTFE (virgin), PTFE with fillers

Technical specifications

• Profile: spiral form
• Design intent: support/back-up ring to prevent seal extrusion in grooves
• Manufacturing material: turned from standard PTFE virgin material; available with fillers
• Groove fit: exactly adapted to groove height; required groove width increases by ring width
• Applicable motion types: static, dynamic, linear, rotatory, oscillating; single and double acting applications
• Maximum pressure (material dependent): static up to 250 MPa; linear up to 40 MPa; rotatory up to 5 MPa
• Temperature capability (material dependent): -200°C to +260°C
• Speed limits: linear up to 0.5 m/s; rotatory up to 2 m/s