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Grinnell Grulok Flanges

Grinnell
Gruvlok Flanges

A. Fig. 7012 and Fig. 7013 Flanges have cast-in tines inside the shoulder I.D. to prevent flange rotation.

B. The sealing surfaces A Max. to B. Min. of the mating flange must free from gouges, undulations and deformities of any type to insure proper sealing of the gasket.

C. Gruvlok Flanges are to be assembled on butterfly valves so as not to interfere with actuator, or handle operation.

D. Do not use Gruvlok Flanges within 90 degrees of one another on standard fittings because the outside dimensions may cause interference.

E. Gruvlok flanges should not be used as anchor points for tie-rods across non-restrained joints.

F. Fig. 7012 & Fig. 7013 Gruvlok Flange sealing gaskets require a hard flat surface for adequate sealing. The use of a metal adapter insert is required for applications against rubber faced valves or other equipment. The adapter insert is installed between the Gruvlok Flange sealing gasket and the mating flange or surface to provide a good sealing surface area..

F1) When mating to a wafer valve (lug valve), if the valve is rubber faced in the area designated by the sealing surface dimensions (A max to B min), place the metal adapter insert between the valve and the Gruvlok flange.

F2) When mating to a rubber-faced metal flange, the metal adapter insert is placed between the Gurvlok flange and the rubberfaced flange.

F3) When mating to a serrated flange surface, a standard full-faced flange gasket is installed against the serrated flange face and the metal adapter insert placed between the Gruvlok flange and the standard flange gasket.

F4) When mating to valves or other component equipment where the flange face has an insert, use the same procedure as described in Note F3.