The stem seal transmits motion from the handle or the controlling device to the disc. The stem physically passes through the bonnet when present. In some cases the stem and the disc combined in one piece, or the stem and the handle are combined in one piece.

Application & Usage

  • Stem can be removed from the ball valve without removing it from the line and this feature lowers the maintenance cost from down time while replacing the stem seals.
  • Stem lubrication fitting provides minimal stem/bonnet corrosion from environmental elements which promotes ease of operation of ball valves and promotes extended valve life.
  • Blowout proof stem can be designed with a higher shear strength shoulders prevention of stem blow out which is a critical for personal safety.
  • Double stem seal can be provided in ball valve assembly and this secondary stem seals provides backup in the event the primary seal fails to hold the flow pressure.

Materials used

Virgin PTFE, Carbon Filled PTFE, Polyfill etc.