Seat Material "Devlon with RPTFE"

[ET1983]

Hi all,

Recently i came across a thing, where we selected RPTFE as the seat material for trunnion mounted ball valve with an operating conditions of max. temp 53 deg C and pressure upto 16.9 barg.

However, the VENDOR has provided / suggested DEVLON seat material against the one we have requested.

when going throught the journals, it says that, DEVLON seat is as good as it is for higher temperature and pressure and corrosive conditions.

My question is Maximum temp of RPTFE seat is considered to be as -100 deg C to 220 deg C (based in vENDOR catalogue)and DEVLON is indicated as -100 deg C to 150 deg C.

Iam confused now whether DEVLON is superior than RPTFE or the vice versa???

 

[ET1983]

To add more to the above question :

The Seat material selection would be based on the Operating Temperature of the fluid or the Design temperature of the fluid. clarify pls.