Seals & Gasketsfor Vacuum Pumps
Shaft seals, O-ring kits, lip seals, head gaskets, end-cover gaskets, exhaust manifold gaskets, and full seal & gasket sets for every major vacuum pump model. FKM, FFKM (Kalrez/Chemraz-grade), NBR, PTFE, and graphite-fibre compounds available for clean, chemical, and high-temperature duty. Next-day UK delivery.
Vacuum pump seals and gaskets are the dynamic and static sealing elements that maintain the vacuum boundary — shaft seals on rotating drives, FKM or FFKM O-rings on end-cover joints, head and exhaust-manifold gaskets on bolted flanges, and PTFE diaphragms on chemistry pumps. Material choice (FKM, FFKM, NBR, PTFE, graphite-fibre) depends on the temperature and chemistry of the duty.
What's included in seals & gaskets
- Shaft seals — single or double lip seals running on the rotating drive shaft to maintain the vacuum-to-atmosphere boundary
- O-rings — static elastomer rings sealing end covers, port flanges, oil galleries, and ISO-K / KF flange connections
- Head gaskets — fibre or graphite gaskets sealing the cylinder head on rotary piston pumps (Stokes Microvac, Kinney KT/KC)
- End-cover gaskets — flat or moulded gaskets on bolt-flanged front and rear end covers of rotary vane pumps
- Exhaust manifold gaskets — sealing exhaust ports and oil-drain connections
- Seal & gasket kits — pre-packaged sets containing every dynamic and static sealing element for a specific pump model, ideal for refreshing sealing without disturbing the vanes. See Service Kits for the full kit-tier breakdown.
- FKM (fluoroelastomer / Viton) — standard for hydrocarbon-oil pumps, good to ~200°C
- FFKM (perfluoroelastomer / Kalrez, Chemraz) — chemical and high-temperature duty, expensive but essential for aggressive process gas
- NBR (nitrile) — economic option for clean, low-temperature duty
- PTFE / graphite-fibre — chemistry pump diaphragms, head gaskets, and inert sealing
When should seals & gaskets be replaced?
Visible oil leak at the drive-end shaft seal
Shaft seal lip wear is one of the most common rotary-vane failure modes. Easy to fix; usually a minor service kit job.
Loss of vacuum after a recent service
An O-ring may have been pinched or twisted on reassembly. Strip and re-seal with new O-rings.
Process change to chemistry duty
Switching from clean to chemical-process duty requires upgrading to FFKM seals and PFPE oil. Standard FKM will swell and fail.
After process upset — solvent slug or hot-gas event
Seals may have been thermally damaged or chemically attacked. Inspect and replace as needed.
How to spot a problem
- Oil weep or leak at drive-end shaft
- Air ingress causing degraded ultimate vacuum
- Hardened, cracked, or swollen O-rings on inspection
- Bluing or charring on the seal lip after a thermal event
- Vacuum decay test failure on a sealed system
Seals & Gaskets by manufacturer
Edwards
Genuine Edwards O-ring sets and shaft seals for E2M, RV, nXDS, GV, and GXS pumps. FKM standard, FFKM upgrade for chemistry duty.
Leybold
TRIVAC and SOGEVAC shaft seal kits, end-cover O-ring sets, and FFKM upgrades for DRYVAC chemistry duty.
Pfeiffer / Adixen
FKM and FFKM seal kits for Pascal SD/C1/C2/I, DuoLine, and HenaLine. C1/C2 chemistry kits use FFKM throughout.
Busch
R5 shaft seal kits, end-cover O-rings, and oil-return valve O-rings — FKM standard, FFKM where required.
Need seals & gaskets?
Tell us your pump model, part number, or just describe the symptom — we aim to come back within 24 hours with a quote and confirmed lead time.