An Alignment Plug centers the disc/stem vertically in the valve bore, maintaining a median gap of .020”. This threaded plug is easily field adjustable, and a set screw secures the position. Horizontal disc/stem alignment is maintained by upper and lower Bushings.
The bronze Bushings absorb actuator side thrust and minimize torque and wear. Additionally, both bushings are inserted externally to leave a smooth, uninterrupted valve bore free of voids and exposed edges. This reduces media entrapment and valve wear. Viton® O-rings prevent leakage through the stem. Two rings form a seal between the bushing and the stem, two rings seal between the bushing and the valve body. Zerk Fittings, through the valve neck and alignment plug, allow a high temperature lubricant to be added when needed to minimize seizing and galling.