E-Series - Ebonite Lined Butterfly Valves

Ebonite lined valves

The Solent & Pratt E series valves are of single or double offset geometry design, developed for high performance, control and isolation duties. They feature integral body seat and resilient seal ring (disc mounted). Similar in construction to the R - series range, they are available in a wide range of castable materials to order in sizes 3" to 84", 150# class.

The E-Series valve has an 'ebonite' lining, which is a hard natural rubber, bonded and autoclave cured to achieve maximum strength and adhesion. It has 'corner locking' overlap features round the flange and shaft bores to maintain optimum stability. The seat contact area, against which the resilient disc seal ring (Nitrile / EPDM / Buna / Viton) locates, is fully machined to ensure consistently tight shut-off, with seal rings of 'flat' or 'music note' design, dependent upon process pressures. These are replaceable parts.

In operation, there is a key difference when compared with some other rubber lined valves. The Ebonite is part of the structural rigidity of the body and the resilient seal is disc located. This is the element being compressed during sealing on closure. This eliminates both dragging on the liner, and creep, which occurs on other valve designs where the disc is solid and sealing is made by compression of the liner. The Ebonite will also provide some resistance to low level slurries / fine particles in the flow and where these are present in any density, then a further back-up shaft bearing seal is available as an option.

Ebonite lined valves

The Ebonite lining used in these products protects the valve material from the line fluid, thus permitting the use of less expensive ferrous metals as opposed to the more costly options such as bronze, stainless steel, monel etc.

The superiority of the Solent & Pratt valve is that Ebonite is a hard natural rubber which is bonded to the internal surfaces of the valve and steam cured in an autoclave to ensure maximum strength and adhesion.

seating area of the lining, against which the replaceable, resilient disc seal locates is fully machined after insertion into the valve body. This ensures consistent “tight shut off” without excessive wear to the seal. The unique feature with this design of rubber lining is that the Ebonite is part of the structural rigidity of the body. The resilient seal located on the disc is the component that is compressed during valve closure. This eliminates both dragging on the liner, and creep, which is associated with lined valves where sealing is obtained by a solid disc compressing the body liner. Valve life is considerably increased with this design.