Non-Contacting, Steam Turbine Gas Seal

Type 28ST combines proven rotating groove technology and high-temperature secondary seals to reduce steam leakage by nearly two orders of magnitude, as compared to traditional sealing devices such as segmented carbon rings and labyrinths.
This steam-lubricated, end-face cartridge seal reacts instantaneously and automatically to maintain a safe face gap despite sudden changes in operating conditions.

A stable seal face gap, typically 0.0025mm to 0.0051mm / 0.0001" to 0.0002", is the result of specially designed rotating grooves, which pump steam radially inward into a nongrooved portion of the seal known as the "sealing dam." This seal is primarily for use on steam turbines.
Design Features

• Bearing oil steam contamination reduced.
• Standard designs fit most single-stage turbines.
• Reduced noise levels and hazards associated with leaking steam.
• Support equipment eliminated.
• Bi-Directional face patterns available

Quick Specs - Refer to datasheet for full specification and limits Temperature40 F to 500 F / -40 C to 260 C
PressureUp to 27.6 bar g / 400 psig
SpeedUp to 122 m/s / 400 fps max.