OD (Outer Diameter) face seals are used on the FLS and FLS-R seat. They are a type of mechanical face seal that's used in conjunction with the ID (Inner Diameter) face seal to provide a seal between the seat and the seat pocket of FLS style valves.

FLS ID and OD face seals are used in all sizes of valves ranging from 1-13/16” to 7-1/16”. The OD seal you’ll receive is spring-loaded and pressure-energized to improve gate and seat service life. Regardless of size, both an ID and OD face seal are required on each seat in the valve.

Face seals from JST have been qualified for pressures ratings of 5,000 -15,000 PSI.

JST can provide two different materials for ID and OD face seals. A common option is virgin peek spring powered by a stainless steel spring/Elgiloy spring. Another option is glass moly filled PTFE with stainless steel springs/Elgiloy spring, which are very durable and can withstand the worst conditions.