Greene, Tweed & Co. Capped GT Rings Series

The Greene, Tweed Capped G-T™ Ring is a double-acting, highpressure piston seal that combines the space-saving and nonextrusion features of more conventional compression-type seals with the low-friction, long-life characteristics of O-ring energized TFE cap-type seals. A positive seal that offers a high degree of sealability in both high and low pressure environments, the CGT™ Ring is designed to handle temperature extremes, a wide variety of fluid media and larger than normal clearances—yet requires a short axial length gland, and assembles and installs easily in the shop or in the field. Further, the CGT Ring is especially suited for long-stroke applications due to its low sliding friction and unique geometry which prevents roll and spiral. ELASTOMERIC SEAL PROBLEMS In designing, with many elastomeric compression-type seals, engineers have to deal with inherently higher friction as well as roll, spiral, nibble and extrusion failure problems which severely limit the performance envelope (Figures 1 and 2). The CGT Ring solves these problems, its geometry providing the high degree of stability necessary to overcome roll and spiral (especially useful in long-stroke applications) and its radially-energized backup rings preventing the “T” shaped elastomeric sealing element or TFE cap from wedging into the diametral clearance or pinching off under motion or pressure (Figure 2). And, because the CGT Ring’s TFE cap is radially loaded in direct proportion to applied pressure levels, frictional losses and wear are reduced to an absolute minimum—while full sealability and prolonged seal life are maintained (Figure 7).