The main valve seat ring material is polytetrafluoroethylene (PTFE). It is almost all chemicals are inert and has a low coefficient of friction , stable performance, easy to aging , wide temperature and excellent tamper proof seals performance integrated features . However, the physical properties of PTFE has a higher coefficient of expansion of the cold sensitivity and poor thermal conductivity, the valve seat tamper proof seal requirements must be designed around these characteristics. The seat seal plastic material, including aliphatic and PTFE Teflon , nylon and other materials .
However , when the sealing material is hardened , the reliability of the pull tight security seals should be destroyed , especially in the case of low pressure differential .
Additionally , such as nitrile rubber, synthetic rubber , can be used seat material , but it applies to the media and to the use temperature range is limited . Further , non-lubricated , synthetic rubber ball stuck easily .
In order to meet the high temperature , high pressure , strong erosion, long life and other requirements of industrial applications , the last decade, metal seated ball valve has been a great development. V- ball valve for regulating the flow also developed rapidly .
Especially in industrialized countries , the ball valve structure continue to improve, as used in the petroleum, natural gas pipeline fully welded ball valve , lift rod ball , ball cracker with temperature regulating valve V -shaped openings , etc. , so that the ball valve technology to achieve a whole new level .
However , when the sealing material is hardened , the reliability of the pull tight security seals should be destroyed , especially in the case of low pressure differential .
Additionally , such as nitrile rubber, synthetic rubber , can be used seat material , but it applies to the media and to the use temperature range is limited . Further , non-lubricated , synthetic rubber ball stuck easily .
In order to meet the high temperature , high pressure , strong erosion, long life and other requirements of industrial applications , the last decade, metal seated ball valve has been a great development. V- ball valve for regulating the flow also developed rapidly .
Especially in industrialized countries , the ball valve structure continue to improve, as used in the petroleum, natural gas pipeline fully welded ball valve , lift rod ball , ball cracker with temperature regulating valve V -shaped openings , etc. , so that the ball valve technology to achieve a whole new level .
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