GB865909A - Improvements in or relating to indicating apparatus for measuring the pressure head or level of liquid relative to a datum level - Google Patents

Abstract

865,909. Valves. DOBBIE McINNES Ltd. Dec. 29, 1958 [Oct. 3, 1957], No. 30954/57. Class 135. [Also in Group XIII] In liquid-level indicating apparatus for measuring, e.g., the liquid level 7 relative to a " zero " datum line in a tank 3 and comprising primary and secondary stand-pipes 1, 10 which can be supplied with compressed air or gas to balance respectively the overall on a fraction of the pressure-head of the liquid, and which are associated respectively with low and high sensitivity manometers 4, 11 whose readings are aggregated to give an accurate level reading (see Group XIII), the secondary stand-pipe 10 consists of a series of detachably interconnected pipes 20 having lower, downwardly-directed branch-pipes 21 which terminate in port openings 21A closable by valves 24 influenced by floats 29. Each port opening 21A is formed through a plastic sleeve 23 which is carried in a metal bushing 25 screwed into the lower end of the corresponding branch pipe 21 and has its upper end moulded to form a valve seating 23A for an associated valve member 24, the stem 25 of which extends through the sleeve 23 and is connected to a lower extension 26 passing through an opening 42 in a cross-piece 41 and carrying a weight 28. An open-bottomed cylindrical float 29 is supported for vertical reciprocating movement on a guide-rod 32 carried at its lower end by a horizontal bracket 33 clamped by a bridgepiece 34 to the branch-pipe 21 and the pipe 20. The cross-piece 41, connected by rods 38 to the float 29 and guided in sleeves 40 in the bracket 33, is engageable by a collar 43 on the stem extension 26 to effect snap opening of the valve 24 upon upward movement of the float 29. Lines 44, Fig. 7, enable the lifting of chosen floats to allow the passage of cleaning medium. Specification 865,908 is referred to.