Page 17 - Tyco-Grooved-Fire-Protection-Products-Installation-Handbook

GENERAL INFORMATION 15
Gasket Specifications 1 of 2
Styles
Standard: The standard style gasket, with a “C” shape configuration, is the most commonly used. It is provided as the standard in the Figure 705 and 577 Grinnell Couplings. The gasket is available in Grade “A” Pre-Lubricated EPDMA and Grade “E” EPDM.
Tri-Seal: The Tri-Seal gasket is designed to close off the gap or gasket cavity. This is accomplished by posi- tioning the center “rib” of the gasket over the gap between the pipes. The Tri-Seal gasket has two tapered sealing edges in addition to the center rib for additional strength and sealing. The Tri-Seal gasket can be used with the Figure 705 and 577 Grinnell Couplings. It is recommended for use in low tem- perature and vacuum services (greater than 10” Hg) applications. The gasket is available in Grade “E” EPDM.
Reducing Coupling: The gasket is pro- vided with ribs used to position the larger pipe so that the sealing lip is located on the sealing surface of the pipe. This gasket is used only with the Figure 716 Grinnell Reducing Coupling and is available in Grade “E” EPDM. Reducing couplings are not recommended for low temperature applications.
Flange Adapter: This gasket is specifi- cally designed for use with the Figure 71 Flange Adapter. The gasket has an optimum amount of rubber to provide a dependable seal between both the pipe and mating surface, and to avoid overfilling of the gasket pocket, which causes assembly difficulties. The gaskets are available in Grade “E” EPDM.
Mechanical Tee: The gasket pro- vides a compression type seal, which is designed to conform to the exterior curve (O. D.) of the pipe. This design is unique to the Figure 730 Mechani- cal Tee (threaded and grooved) and the 40-5 Strap Outlet. The gaskets are available in Grade “E” EPDM.