Wedged Back-Up Rings
As exploration and production of oil and gas reserves go deeper and hotter, sealing technologies must keep pace to withstand increasingly hostile conditions for longer periods of time.
Parker’s wedged back-up rings extend seal life by preventing extrusion of elastomeric seals in high pressure, high temperature environments. Under high system pressure, the elastomer seal applies an axial force on to the wedged back-up set. This axial force allows the wedged halves of the back-up set to slide along their common angle and bridge the metal gland clearance gaps; preventing extrusion of the primary sealing elastomer.
Product Highlights:
- Two-piece design with common angle
- Split for easy installation
- May be designed to replace 0-ring back-ups for higher pressures
Product Features:
- Two-piece design with common angle
- Split for easy installation
- May be designed to replace 0-ring back-ups for higher pressures
- Universal sizing
- Machined to fit any size combination
- Available in filled and non-filled PEEK, Nylatron”‘ and filled PTFE blends
Preventing Extrusion
How Wedged Back-ups Work
Wedged back-up rings are used to protect the main sealing elements in high pressure applications. The WB Profile is not a seal, but is used in conjunction with elastomeric seals to bridge the metal gland extrusion gaps and prevent the elastomeric seal from extruding.
As pressure contacts the main seal upstream from the back-up rings, the sealing systems are forced to the point of least resistance which is the extrusion gap (Fig. 1 and 2). Since the seal is positioned on top of the back-up ring set, as pressure increases, it comes in contact with the back-up set. Pressure acts on the common-angled back-up rings causing them to slide apart. As they do, the respective ID and OD shift to their points of least resistance and close off the extrusion gap — providing zero clearance for the softer elastomer. With the gap eliminated, sealing becomes more effective and longer lasting despite extremely high system pressures.
Double-Acting
Two wedged-back-up ring sets can be used in double-acting applications with one back-up positioned downstream of each pressure direction (Fig 3). This design allows seals to function in static or dynamic applications under high pressure and high temperature conditions. The rigid back-up ring design has little effect on breakout and running friction. Depending upon the material selected, the split design facilitates intallation on solid pistons without necessity of auxiliary installation tools.
This warranty comprises the sole and entire warranty pertaining to items provided hereunder. seller makes no other warranty, guarantee, or representation of any kind whatsoever. All other warranties, including but not limited to, merchant ability and fitness for purpose, whether expressed, implied, or arising by operation of law, trade usage, or course of dealing are hereby disclaimed. Notwithstanding the foregoing, there are no warranties whatsoever on items built or acquired wholly or partially, to buyer’s designs or specifications.
Limitation of remedy: Seller’s Liability arising from or in any way connected with the items sold or this contract shall be limited exclusively to repair or replacement of the items sold or refund of the purchase price paid by buyer, at seller’s sole option. In no event shall seller be liable for any incidental, consequential or special damages of any kind or nature whatsoever, including but not limited to lost profits arising from or in any way connected with this agreement or items sold hereunder, whether alleged to arise from breach of contract, expressed or implied warranty, or in tort, including without limitation, negligence, failure to warn or strict liability.
- Details
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Product Features:
- Two-piece design with common angle
- Split for easy installation
- May be designed to replace 0-ring back-ups for higher pressures
- Universal sizing
- Machined to fit any size combination
- Available in filled and non-filled PEEK, Nylatron”‘ and filled PTFE blends
Preventing ExtrusionHow Wedged Back-ups Work
Wedged back-up rings are used to protect the main sealing elements in high pressure applications. The WB Profile is not a seal, but is used in conjunction with elastomeric seals to bridge the metal gland extrusion gaps and prevent the elastomeric seal from extruding.As pressure contacts the main seal upstream from the back-up rings, the sealing systems are forced to the point of least resistance which is the extrusion gap (Fig. 1 and 2). Since the seal is positioned on top of the back-up ring set, as pressure increases, it comes in contact with the back-up set. Pressure acts on the common-angled back-up rings causing them to slide apart. As they do, the respective ID and OD shift to their points of least resistance and close off the extrusion gap — providing zero clearance for the softer elastomer. With the gap eliminated, sealing becomes more effective and longer lasting despite extremely high system pressures.
Double-Acting
Two wedged-back-up ring sets can be used in double-acting applications with one back-up positioned downstream of each pressure direction (Fig 3). This design allows seals to function in static or dynamic applications under high pressure and high temperature conditions. The rigid back-up ring design has little effect on breakout and running friction. Depending upon the material selected, the split design facilitates intallation on solid pistons without necessity of auxiliary installation tools.
- Specs
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- Resources
- Warranty
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This warranty comprises the sole and entire warranty pertaining to items provided hereunder. seller makes no other warranty, guarantee, or representation of any kind whatsoever. All other warranties, including but not limited to, merchant ability and fitness for purpose, whether expressed, implied, or arising by operation of law, trade usage, or course of dealing are hereby disclaimed. Notwithstanding the foregoing, there are no warranties whatsoever on items built or acquired wholly or partially, to buyer’s designs or specifications.
Limitation of remedy: Seller’s Liability arising from or in any way connected with the items sold or this contract shall be limited exclusively to repair or replacement of the items sold or refund of the purchase price paid by buyer, at seller’s sole option. In no event shall seller be liable for any incidental, consequential or special damages of any kind or nature whatsoever, including but not limited to lost profits arising from or in any way connected with this agreement or items sold hereunder, whether alleged to arise from breach of contract, expressed or implied warranty, or in tort, including without limitation, negligence, failure to warn or strict liability.
