PTFE is a self lubricating engineering material of construction which can markedly improve the performance and service life of wear elements, seals and other key components of hydraulic pneumatic and mechenical system. when used in its virgin state, this materias offers the design engineer a unique set of basic properties including a co-effieient of friction lower than that of graphite, outstanding temperture resistance and corrosion and chemical reistance equal to of better than that of glass. when compounded with inorganic filers or when used as an internal lubricant for other thermoplastics, it possesses a wear resistance comparable to many softmetal alloys and superior to most other self lubrication materials. PTFE posseses many special properties which are the particular interest to the mechenical, hydraulic and pneumatic engineer, such as freedom from stick slip, an exellent plastic memory and an ability to absorb contaminants. because of these basic and special property advantage. PTFE can used in many difficult application where hostile environment of operating restriction cause early failure of entirely preclude the use of lubricants and parts constructued form other materials. it can simplify the design and lower cost of system where there are no unusal application difficulties by eliminating the need for lubrication, permitting standrazation of construction materials and performaing a multiplicity of function. A potential application for PTFE exist in particularly any machanism involving sliding, oscillating or rotery contace between parts and any static application involving corrisive chemical severe weathering of exteme operating temperatures.
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TYPICAL PROPERTIRES OF PTFE |
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PROPERTY |
UNITS |
METHOD |
VALUES |
|
Specific gravity |
g/cm3 |
ASTM D 7792 |
2.14-2.18 |
|
Tensil strength |
N/mm2 (1) |
ASTM D 1457 |
20-35 |
|
Elongation at break |
% |
ASTM D 1457 |
210-400 |
|
Compressive Strength 1% deformation |
% |
ASTM D 1457 |
4-4,5 |
|
Deformation under load (14 N/mm2/24 hrs) |
% |
ASTM D 621 |
10-15 |
|
Flexural Strength (70 N/mm2) (1) |
N/mm2 (1) |
ASTM D 790 |
No breaking |
|
Impact strength (izod) |
N/mm2 (1) |
|
|
|
57C 23C 77C |
J/Cm (1) J/Cm (1) |
ASTM D 256 ASTM D 256 ASTM D 256 |
ASTM D2561,1 1,6 3,3 |
|
Hardness (Shore D) |
---- |
ASTM D 2240 |
50-60 |
|
Friction Coeficient Static Synamic |
---- ---- |
(2) (2) |
0.09 0.05 |
|
PTFE steel oil lubricant |
|
|
0.02-0.06 |
|
Melting point |
C |
|
320-340 |
|
Increase in volume from room temperature to moltan state (340C) |
% |
---- |
27-28% |
|
Coefficient of thermal expansion From 25 to 100 C From 20 to 200C |
0C-1 X 10-5 0C-1 X 10-5 |
Dilatometer Dilatometer |
16 19 |
|
Thermal Conductivity |
W/m 0K(1) |
Cenco-Fitch |
0,23 |
|
Specific Heat At 0C At 50C |
Kj/kg, 0K (1) Kj/kg, 0K (1) |
---- ---- |
0,96 1.05 |
|
Temperature of distortion At 0.46 N/mm2 (1) At 1.85 N/ mm2 |
C C |
ASTM D648 ASTM D648 |
130-140 50-60 |
|
Dielectric strength (Short time, air, thickness 0.5mm) |
Kv/mm |
ASTM D149 |
55 |
|
Dielectric Constant (50-10 Hz) |
--- |
ASTM D150 |
2,1 |
|
Dissipation factor |
---- |
ASTM D150 |
<0,0002 |
|
Volume resistancy |
Ohm/cm |
ASTM D257 |
1017 |
|
Surface resistance 100% r.h. |
Ohm/cm |
ASTM D257 |
1015 |
|
ARC-resistance 420sec |
Sec |
ASTM D495 |
Without defects |
|
Water absorption |
% |
ASTM D570- |
<0,01% |
|
Inflammability ATB ATB |
Sec Mm |
ASTM D635 ASTM D635 |
<5 <5 |