Gaskets in FKM: properties and advantages

One of the strengths that have allowed GB Srl to become a leader in the industrial sector is, without a doubt, the network of qualified laboratories with which we collaborate in defining and developing the materials for the most innovative and high-performance moulding in rubber. A form of collaboration that allows us to identify, or when necessary, create, the material best suited to your projects, guaranteeing products of optimised standards.

One of the categories of material that we handle is high-quality thermoplastics and elastomers, such as FKM, currently considered to be one of the highest-quality rubbers on the market. It out-performs, sometimes tenfold, standard rubbers, and is well-known for its excellent chemical resistance and its ability to withstand elevated temperatures. 


When and why is it the right choice for your projects? 


What is FKM?

Technically, FKM is a fluoroelastomer, i.e., a synthetic technopolymer used in applications that require an elevated level of technology, reliability and sturdiness. The material is part of the M group of rubbers and is characterised by a saturated carbon backbone. 


There are three types of FKM, which differ in terms of fluorine content and monomer count of the polymer, i.e., copolymers, terpolymers and tetrapolymers. FKM elastomers are usually based on vinylidene fluoride and hexafluoropropylene copolymers, or terpolymers of these two monomers together with tetrafluoroethylene.


FKM is commercially available under a range of brand names (the main ones are Tecnoflon®, Dai-El® and Viton®). In general, FKM is chosen for the manufacture of durable and sturdy products that manage to satisfy even the most particular and challenging application requirements.

Characteristics of FKM 

The material is of excellent quality, and its properties mean that it can be considered an extremely versatile elastomer that guarantees extraordinary resistance to extensive mechanical, physical and chemical stress.

The main characteristics of this material are its resistance to high temperatures and chemical agents, but on closer analysis of FKM, the many particular characteristics of this elastomer emerge. 


Its physical-mechanical characteristics include:

– good to excellent resistance to high temperatures.

– excellent resistance to chemical agents.

As mentioned, FKM also offers resistance to flame, UV radiation and high temperatures (up to 230° or 275° according to its formulation), is impermeable to air and gas, and has optimal dielectric properties. 


From a chemical point of view, FKM stands out for its excellence and the advantages it offers. This material offers perfect resistance to: 

– vegetable, mineral and animal oils and fats. 

– aliphatic, aromatic, chlorinated hydrocarbons.

– seawater and saline solutions. 

– fuels free of methanol additives. 

– hydrochloric acid. 

– sulphuric acid. 

– ozone and other atmospheric agents. 

– dielectric synthetic oils. 

– silicone-ester-based hydraulic fluids. 


It also reacts in an excellent manner to diester-based synthetic lubricants, water vapour (up to 140 °C), freon, and nitric acid at room temperature. 


On the contrary, FKM cannot be used in applications that require contact with methanol, ketones, esters, some non-petroleum-based brake fluids and medium- and high-concentration alkali. 


FKM: o-rings, gaskets and endless uses

FKM is a sealing material that can be successfully used in all of the GB Group production processes for the creation of products suited to the widest range of sectors. For example, this elastomer is used in the automotive sector, in the aerospace industry, in energy supply systems (for example in the cooling systems for wind turbines), in the chemical and petroleum industry or for the manufacturing of a range of home appliances. 


It is therefore particularly suited to projects that require high-level seals and excellent service requirements, as part of complex installations. 


As well as only selecting the most valid suppliers of the FKM used in our products, we carefully check the quality of every roll or sheet of FKM as soon as it arrives at our plants, and we make sure that every phase of the production process is aimed at maintaining the reliability of the component


It is important to note that FKM presents significant complexities in handling the moulding process, above all because it is extremely fragile at high temperatures. In order to be certain of the final yield for products and gaskets made from FKM, it is essential to rely exclusively on suppliers who, like GB Group, can guarantee firmly based competence in the field and who are able to come up with the best solution for products that make the most of the characteristics of this efficient raw material. 


GB and GBL: a complete ecosystem for all your needs 

Choosing FKM as a material for the production of high-performance gaskets means investing in the durability of your systems and in satisfying your most detailed requirements. 


Since 1976, we have been constantly focused on the production of industrial gaskets to design in rubber and thermoplastic material, drawing on the know-how of specialised technicians and the fruitful sharing of skills that is typical of the Bergamo rubber district. We are certified in accordance with regulation IATF 16949 (for the automotive sector) and oriented to constant investment for the optimisation of our products, our capabilities, and the technological innovation of our services.

The experience gained by GB has also led to the founding of GBL, one of the companies in our network (together with GBS). The company is specialised in particular in the manufacture of high-and low-pressure fluid power and hydraulic seals, and also uses the most advanced rubber, rubberised fabric and thermoplastic construction materials.


The two companies focus on different areas, but they share a number of characteristics, such as a cutting-edge machine inventory, constantly updated quality certificates, a qualified team, extensive flexibility in production, strict quality controls throughout the workflow, and an efficient network of external partners for increased opportunities.

If you are looking to design and manufacture your gaskets in FKM, we can serve as a trusted partner that knows how to help you to achieve the best performance. Contact us