Rubber Seals
FFKM O-Rings
FFKM O-rings exist for the applications where every other elastomer has already been ruled out.
View product →
Rubber Seals
FKM and FFKM O-Rings
FKM and FFKM sit at the top of the seal material range and are frequently confused with each other. FKM is a high grade fluoroelastomer with strong resistance across chemicals and temperatures, covering petroleum products, hydraulic fluids and acidic compounds. FFKM goes further, withstanding even aggressive chemicals, and belongs in semiconductor manufacturing and chemical processing. We supply both and will tell you which one your application actually needs.
Why It Wins
Key Benefits
- FKM resistance across petroleum products hydraulic fluids and acidic compounds
- FFKM for near universal chemical resistance where FKM reaches its limit
- Both grades available from one supplier so the comparison is honest
- Standard AS568 sizes from existing moulds and custom cross sections tooled here
- Small quantities of high specification compound accepted rather than refused
The Brief
Problems It Solves
- Seals degrading in fluids that general purpose elastomers cannot handle
- Paying FFKM prices for an application FKM would cover
- Under specifying and paying for it in unplanned downtime
- Suppliers who will not quote small quantities of a specialised compound
Audience
Who It Is For
- Process engineers specifying seals against a defined chemical list
- Semiconductor and electronics plant maintenance teams
- Buyers who have been quoted FFKM and want to know whether FKM would do
- Distributors carrying a high specification seal range
In Service
Application Scenarios
- Chemical processing seals for reactors mixers and transfer systems
- Semiconductor manufacturing equipment
- Petroleum and hydraulic systems
- High temperature engine and fuel system components
- Equipment handling acidic compounds
Specification
What You Are Actually Buying
Only values our own records support appear here. Anything we cannot evidence is left out rather than estimated.
| Materials | FKM fluoroelastomer and FFKM perfluoroelastomer |
|---|---|
| FKM Suited To | Petroleum products, hydraulic fluids, acidic compounds |
| FFKM Suited To | Aggressive chemicals and solvents, semiconductor and chemical processing |
| Standard Sizes | AS568 series from moulds held in house |
| Custom Sizes | Tooled to drawing |
| Country of Manufacture | China |
Materials
- FKM
- FFKM
Manufacturing Process
- Compound selection
- Mould selection or tooling
- Moulding
- Post cure
- Inspection
- Packing
Detail
Technical Features
- FKM fluoroelastomer for wide chemical and temperature resistance
- FFKM perfluoroelastomer for the most aggressive chemistries
- Precision moulded cross sections for consistent sealing
- Available across the AS568 size series and to custom drawing
How We Check
Quality Control
- Compound chosen against the stated chemistry by our formula engineers
- First article approved before series production
- Dimensional check against the approved sample
- Repeat orders run from the same formulation and tool
Made to Order
Customisation Options
- FKM or FFKM in any AS568 dash number
- Custom cross sections tooled in our own workshop
- Small pilot quantities for qualification before volume
- Supplied within a mixed compound schedule
Honest Comparison
Where This Is the Right Choice and Where It Is Not
Compared With FFKM alone
For most demanding industrial fluids FKM is adequate. Specifying FFKM by reflex spends money on chemical margin the application never uses.
Compared With NBR
Nitrile covers oil and fuel at moderate temperature and nothing like this chemical range.
Compared With EPDM
EPDM is for water, steam and weather. It has no place in petroleum or aggressive chemical service.
Use Guide
How to Specify and Order This Part
List every fluid including cleaning agents and occasional exposure
Give continuous and peak temperature separately
Ask for samples of both grades where the choice is genuinely marginal
Use an AS568 dash number where the groove allows it
Record the service life achieved so the next specification is data driven
Related Products
Rubber Seals
FFKM Material Seals
Not every FFKM application is an O-ring.
View product →
Rubber Products
FKM Rubber Parts
This is FKM outside the sealing catalogue: custom moulded fluoroelastomer parts made to a customer drawing.
View product →
Rubber Seals
O-Rings
An O-ring is the cheapest part in most assemblies and the most common cause of a warranty return.
View product →Related Guides and Industries
Guide
FFKM or FKM Which One Your Application Actually Needs
FFKM is not simply a better FKM. It is a different commercial decision, and specifying it by reflex wastes money as reliably as under specifying wastes uptime.
Read the guide →
Guide
How to Choose a Rubber Seal Material in Six Questions
Six questions decide almost every seal material choice. Answer them before you ask for a price, and the quotation you get back will be worth comparing.
Read the guide →Answers
FKM and FFKM O-Rings Questions
What is the difference between FKM and FFKM?
FKM is a fluoroelastomer with strong resistance across a wide chemical and temperature range. FFKM is a perfluoroelastomer whose resistance is close to universal, at higher cost.
Which one do I need?
Tell us the chemistry and the temperature, and what a failed seal costs you. We will recommend the lower grade where it is genuinely safe.
Can you supply small quantities of FFKM?
Yes. Small quantities of high specification compounds are normal in semiconductor and laboratory work.
Are these available in AS568 sizes?
Yes, from the complete mould set we hold.
Can you tool a special cross section in FKM?
Yes. Our own mould workshop designs and builds the tool.
How long does a quotation take?
One working day once we have the chemistry, the size and the quantity.
Quote FKM and FFKM O-Rings
Send the size or drawing, the working conditions and the quantity. One working day for a considered reply.