Five-Valve Manifolds

A five-valve manifold is a three-valve manifold with both drain / vent valves brought into the same block: two process isolation valves, one equaliser, and a vent on each leg. It is what a differential pressure instrument needs when both legs have to be vented without breaking a joint.

Three remote-mounted models are published. 5 RM1 and 5 RM3 carry separate drain / vent connections on different body forms; 5 RM2 brings them onto a common drain with the drain in front, which is one drain line instead of two. All three sit away from the instrument on tube or pipe impulse lines.

Three mount direct. 5 DM1 puts the vent valves on the side and the rest on top, angled to clear the instrument. The "T" type is screwed on the process side and flanged on the instrument. The "H" type is flanged on both, so it will go direct or remote on oval / kidney flanges, with the drain on one side and an optional bottom test port. The coplanar manifold assembles onto the base of particular transmitter models, with two bottom test ports supplied plugged.

Dimensions across the range are for the standard 54 mm (2 1/8 in) instrument centre distance, with other centres made to suit. Hydrostatic test is 620 kg/cm² on the body and 413 kg/cm² on the seat with a 40 kg/cm² pneumatic seat test; gland packing is PTFE as standard and Graphoil above 180 °C.