Batescrew Extreme Head Valves
describes the method of attaching the valve, the type and arrangement of
control mechanism, and ancillary items such as support towers.
Smaller valves, with a single screw mechanism, may be installed using any of the conventional mounting methods eg. headwall mounting, grouted, flanged, gibault type rubber-ring joiners. The very large valves with dual screw control are usually welded directly to pipes.
SINGLE SCREW VALVES This applies to valves up to and including 2400mm nominal
The operating height
of the gearbox may be made lower than normal, by having a sealing gland at the top of the
body and the control screw mounted externally.
The screw is connected to the door by a stainless tube, passing
through the gland. A standard
angle gearbox is mounted on a frame, at a height to accommodate thread
A diagram of this arrangement, with the minimum height achievable (A9), can be seen on the dimension sheet. Dimensions.
TWIN SCREW VALVES
This applies to valves of three metres nominal bore, and larger.
Cylindrical spigots can be provided on both sides of the valve, for insertion within a pipeline. These may be of unequal diameter, if required.Headwall mounting can be provided by flanged square spigots, which are more cost-effective than conventional circular flanges.