Rotary shaft seals for Chemical.
Chemical service is where conventional seals go to die. Strong oxidizers attack elastomers; chlorides pit standard stainless; thermal cycling fatigues anything cast. We build for chemical plants from solid bar stock, with FFKM secondaries and a hydrostatic test record on every unit.
01The challenge
Why sealing this service is hard.
These are the failure modes our application engineers have catalogued from twenty-five years of chemical installations. Most are visible only after a seal has been pulled.
- 01
Chloride stress-corrosion cracking
Standard 316L pits in chloride service above 140 °F. We offer Hastelloy C-276 wetted parts on the 9700-CHEM variant for chlorinated solvents and concentrated brine.
- 02
Permeation through standard elastomers
FKM is permeable to aromatic solvents over 200 °F. FFKM (Kalrez/Chemraz) is the only secondary that holds in continuous service on toluene, MEK, and chlorinated solvents.
- 03
Vacuum and pressure cycling
Reactor service often cycles from full vacuum to 30 psig many times per batch. A balanced cartridge seal handles this; an unbalanced design fatigues the secondary.
- 04
Zero-emission VOC compliance
EPA NESHAP and state air-permit programs require documented zero-emission seal systems on toxic-organic service. The AST60-API53A pressurized barrier seal is our standard recommendation.
02Recommended series
What we ship for chemical.
03Common equipment
Where we typically install in chemical plants.
04Compliance & materials
Documentation we ship with the seal.
- PED 2014/68/EU pressure equipment directive (export models)
- ATEX zone 1 / zone 21 hazardous-area certification on 9700 variants
- EPA NESHAP zero-emission qualified configurations available
- Hastelloy C-276, Alloy 20, and Inconel 625 wetted-part options
05Engineering FAQ
What plant engineers ask before specifying.
Chemical · sized in 24 hours
Get a recommendation for your chemical application.
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