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| Flexible Member |
1)NBR: NBR is the
copolymer of butadiene and acrylonitrile polymerize at the suspend
liquid.
2)HNBR: Its
properties is better than NBR, applied temperature
from -40 to 150 degree centigrade, it is better exist
in H2S than Vtion does, and exist better in oil than
NBR does.
3)Fluoro rubber: Fluoro
rubber is the polymer which contents F. The fluoro rubber of
Chinese code are two types: F-23 which equivalent to Kel-F and
F-26 which equivalent to Viton. Fluoro rubber has the excellent
properties such as heat resistance, matches well with oil, anti-corrosive
and vaccum resistance, but fuoro rubber is not suitable in the
liquids such as ketone and este and cold resistance is not good,
huge change on permanent deform after it was pressed.
4) EPM: EPM
is the polymer of ethene and propylene，include
terpolymer and binary copolymer. Normally,
Trisun use EPDM.
5) Siliocn Rubber: Silicon
rubber is composite by organic Si and hydrocarbon.
Good performance on heat and cold resistance,
small change of permanent deform after it was
pressed，excellent on electric spread. The disadvantage
are worse tear and wear resistance at the average
temperature than other material rubbers, and
it can not be used in the mineral oil with
lower boiling point, it will be easy decomposed
at the environment with high pressed water
steam.
6) PTFE: It
has a wide application range of temperature
from -150 to 250 degree centigrade, extremely
low friction coefficient and self-lubricate，it
will not felt on its surface，its chemical characteristics
are stable. The only matter which can corrode
this kind of material is melted alkali metal
and the F element in high temperature and pressure.
It will changed in any temperature under the
effect of burthen, when the temperature above
343 degree centigrade it will decompose and
release poison smoke.
7) CR,
HR and epichlorohydrin rubber etc. also can
be used for secondary seal ring.
8) Soft
carbon, adbestos and the composited material
of rubber and plastic also can be used in secondary
seal ring but in high temperature environment. |
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