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Polytetrafluoroethylene (P.T.F.E.) is
a truly unique material and is still the most widely
used of all the fluropolymers.
Unfortunately virgin P.T.F.E.
exhibits high elastic deformation under load which
considerably reduces its value as a bearing surface.
This situation is dramatically improved by the use of
fillers. Filled grades of P.T.F.E. are often used for
more demanding applications, however only virgin
material is suitable for direct contact with food.
P.T.F.E. can be machined using
conventional tools, however close tolerance work may
prove difficult to achieve particularly when machining
components with thin sections.
Please note smoking during any
machining process should be prohibited.
Virgin PTFE datasheet
|
Properties |
Method |
Unit |
Typical Values (from-to) |
|
Specific gravity |
ASTM D792 |
- |
2,14 - 2,20 |
|
Tensile strength |
ASTM D1457 |
N/mm2 |
20 - 35 |
|
Elongation at break |
ASTM D1457 |
% |
210 - 400 |
|
Compressive strength 1%
deformation |
ASTM D695 |
N/mm2 |
4,00 - 4,50 |
|
Deformation under load 14 N/mm2
for 24hrs |
ASTM D621(1) |
% |
10 - 15 |
|
Flexural strength 0,7 N/mm2 |
ASTM D790 |
N/mm2 |
no break |
|
Impact strength (Izod) 57°C |
ASTM D256 |
J/cm |
1,10 |
|
Impact strength (Izod) 23°C |
ASTM D256 |
J/cm |
1,60 |
|
Impact strength (Izod) 77°C |
ASTM D256 |
J/cm |
3,30 |
|
Hardness |
ASTM D2240 |
(shoreD) |
50 - 60 |
|
Friction coefficient - static |
ASTM D3028 (2) |
- |
0,09 |
|
Friction coefficient - dynamic |
ASTM D3028 (2) |
- |
0,05 |
|
PTFE - steel oil lubricated |
- |
- |
0,02 - 0,06 |
|
Working temperature range |
- |
°C |
-200 / +260 |
|
Increase in volume from room
temperature to molten state
(340°C) |
- |
% |
27 - 28 |
|
Coefficient of thermal expansion
from 25 to 100°C |
ASTM E831 |
°C-1 |
16 x 1-5 |
|
Thermal conductivity |
ASTM D2214 |
W/mK |
0,20 |
|
Specific heat 0°C |
- |
KJ/kg.K |
0,96 |
|
Specific heat 50°C |
- |
KJ/kg.K |
1,05 |
|
Temperature of distortion 0,46
N/mm2 |
ASTM D648 |
°C |
130 - 140 |
|
Temperature of distortion 1,85
N/mm2 |
ASTM D648 |
°C |
50 - 60 |
|
Dielectric strength (short-time
air thickness 0,5 mm) |
ASTM D149 |
kV/mm |
55 |
|
Dielectric constant |
ASTM D150 |
- |
2,10 |
|
Dissipation factor |
ASTM D150 |
- |
<0,0002 |
|
Volume resistivity |
ASTM D257 |
Ohm/cm |
10-17 |
|
Surface resistivity |
ASTM D257 |
Ohm |
10-15 |
|
Arc-resistance |
ASTM D495 |
sec |
OK
(4) |
|
Water absorption |
ASTM D570 |
% |
<0,01 |
|
Flammability ATB |
ASTM D635 |
sec |
<5,00 |
|
Flammability AEB |
ASTM D635 |
mm |
<5,00 |
Note:
All the values refer to the temperature of
23°C unless otherwise specified
(1) Superseded standard
(2) Speed 5 m/min; load 1kg/cm2, sliding
surface steel roughness Ra = 0,4 " 0,6
micron
(3) 100% relative humidity
(4) Without defects |
Moulded Virgin P.T.F.E.
Moulded 25% Glass filled P.T.F.E.
Skived
Virgin P.T.F.E.
Extruded
Virgin P.T.F.E.
Extruded 25% Glass filled P.T.F.E.
Extruded 25% Carbon filled P.T.F.E.
Tubing coils
-
Thin wall tubing (metric)
-
Thin wall tubing (imperial)
-
Electrical sleeving super thin
wall
-
Electrical sleeving thin wall
-
Electrical sleeving heavy wall
A list of the most common Sizes etc
that are readily available as standard items can be down
loaded
here
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