It is designed according to BS-1873 and ASME B16.34 standards. The flow direction is from below the disc upwards.
Closure member is conical-shaped, assuring the seal tightness by mean of a uniform seating stress all around the seating circumference. The disc is guided depending on size and pressure, and it can be provided with a needle-shaped extension if it is required a high precision in a throttling service.
Seat rings are screwed to the body, welded or not depending on size, and they can be machined in the body for valves in austenitic material, it means, integral seat. Both types are renewable, fulfilling all the international applicable standards.
Disc-to-stem connection is made by means of a retainer. The disc is loosely attached to the stem, it rotates free relative to the stem in order to allow a proper seating and reduce the wearing of the seating surfaces.
Its duties are stopping and starting flow, and controlling the flow of a fluid. Suitable for frequent valve operations.