PTFE semi-finished products0 pages

PTFE semi-finished products and
finished parts

Material characteristics

Enveloped gaskets*
Steering floaters

PTFE = Polytetrafluorethylene

Spheres

PTFE is excellently suited as a construction material for the
chemicals industry. It temperature resistance ranges from -190
°C to +250 °C, and it can temporarily sustain temperatures of
+300 °C. Because of its low friction coefficient, it is used as an
anti-friction coating and lubrication material. Because of its particularly high insulation resistance and puncture resistance, it
can also be used for insulation purposes.
Another specific characteristic of PTFE is its extremely anti-adhesive property. As a result of its non-stick effect, no substances
adhere to PTFE surfaces. PTFE is non-flammable, does not
absorb water and is physically harmless to humans. PTFE is
considered to be a member of the thermoplastics group, although it is not suitable for injecting or pouring.
PTFE is resistant to nearly all chemicals. It is only susceptible to chlorine trifluoride, elementary fluoride and melted
alkali metals. Additionally, PTFE will not swell or dissolve in
any common organic and inorganic solvent, even at high
temperatures. It belongs to the group of weather-resistant
plastics.

Standard types
Filler material
Filler material content [%]

6.3001 6.2509 6.3105 6.3231 6.3303
none

Coal

0

25

Glass Bronze Graphite
25

60

15

Please contact Kempchen to request materials with other filler
materials and filler content.

PTFE without filler material
Pure PTFE is used for applications requiring high chemical
resistance, strong anti-adhesive properties or very low friction values.

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Construction parts
* see section “PTFE-enveloped gaskets”

PTFE-Compositions
By combining pure PTFE with various filler materials, individual physical and mechanical properties can be positively
influenced. It is important to consider that other properties
may be negatively influenced in the process.
The following are the primary results to be attained by using
PTFE-types with filler material:
Reduction of cold flow
Increased regidity at high temperatures
greater heat conduction
greater abrasion resistance
The main filler materials used are glass, coal, graphite and
bronze.

Material types
Material no.

Back-up rings

PTFE without filler material may be unsatisfactory for certain
areas of application. Unsatisfactory characteristics that may
arise include a tendency to cold flow under pressure and
relaxation at temperatures, the mechanical resistance and
the low capacity for heat conduction. PTFE without filler is
used for
Bellows
O-rings

PTFE Glass
Adding glass powder drastically reduces the tendency for
cold flow in comparison to pure PTFE. This composition has
shown superior performance in all types of applications, but
particularly
Valve rings
Flat gaskets*
Sealing cones
Bearings
V-ring packings
* See the section “PTFE enveloped gaskets”

PTFE Coal
PTFE coal compound is characterised by a low abrasion
and high stability. This composition is commonly used as a
material for bearings, particularly at very low temperatures.
The PTFE coal composition requires special caution when
manufacturing moulding blanks for the machining of piston

Kempchen Dichtungstechnik GmbH · Tel. +49 (0)208 8482 0 · Fax. +49 (0)208 8482 285 · info@kempchen.de · www.kempchen.de

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PTFE semi-finished products and finished parts