GB1322702A - Multistage self-priming centrifugal pumps - Google Patents

Abstract

1322702 Centrifugal pumps HENRY SYKES Ltd 6 July 1970 [18 April 1969] 19886/69 Heading F1C A multi-stage self-priming centrifugal pump having a first stage 10, Fig. 1, associated with a priming pump 13 connected via conduit 14 with float chamber 15 generally as described in Specification 1048272, has valve assemblies 29 connected to inlet conduits 27 or, as shown, inlet chambers 25, 26 of the second stage 11 and subsequent stages 12 if any. Once the first stage is primed by the pump 13, air downstream thereof becomes compressed and thereby forces its way through the second stage valve assemblies 29 to the atmosphere via bores 36. Thus the second stage is primed and subsequently, in a similar manner, the third stage becomes primed. The consequent filling of chambers 25, 26 with water raises floats 32 of the valve assemblies 29 and thereby closes the bores 36 with the upper end of valve heads 34. Normal pumping proceeds and the water is discharged through a non-return valve 16. Each valve assembly may additionally be connected to chamber 15 and thereby communicate with the priming pump. The stages may comprise individual units, and the first stage may comprise a single entry pump of the kind described in Specification 755249.