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BK SPIRAL
Description
The Back-Up Ring reference number is the same as the reference number of the respective OR. Example: OR 3075 is used with Back-Up Ring BK 3075 Anti-extrusion/Back-up Rings are made of Virgin PTFE. PTFE (polytetrafluoroethylene) displays an interesting range of peculiar characteristics:
  • • Complete chemical inertia, meaning that it resists attack by almost all chemical compounds and, above all, it does not alter the fluids with which it comes into contact.
  • • Complete insolubility in water and any organic solvent.
  • • Excellent dielectric properties.
  • • Excellent heat resistance.
  • • Excellent sliding properties, minimal coefficient of friction.
  • • Self-lubricating and excellent resistance to aging.
ASSEMBLY DIMENSIONS IN MM
O-Ring
Cross-Section		 Groove depth Groove width E max R max
Cylinder ØB (h9) Rod ØB (h9) G2 (+0.2) G3 (+0.2)
1.78 A - 2.9 A + 2.9 3.8 5.2 0.13 0.2
2.62 A - 4.5 A + 4.5 4.7 6.2 0.13 0.3
3.53 A - 6.2 A + 6.2 6.0 7.7 0.15 0.4
5.33 A - 9.4 A + 9.4 8.7 10.8 0.17 0.4
7.0 A - 12.2 A + 12.2 12.0 14.7 0.25 0.6
ASSEMBLY DRAWING
Disegni 3D