Multistage pump using a steel intermediate casing and intermediate casing

摘要

PURPOSE: To prevent an influence from being exercised on a weld through receipt of deformation owing to the pressure of an impeller only by the body part of a casing and to prevent breakage of the weld part by a method wherein a cone-form overhang part extending to the inlet side of an impeller is formed to the bottom part of a cylindrical casing. ;CONSTITUTION: A casing 20 is formed such that a cylinder part 25 and an escape part 26 are formed between a side part 21 and a bottom part 24 and a plane part 27 is connected to a side part 21 through a protrusion part 28. In this case, the bottom part 24 has the hole 24A side, i.e., a central part, in which a liner ring 30 is inserted and which is protruded in a cone-shaped part 31 toward the interior of a casing in which an impeller 32 is contained. the protrusion size 6 of the cone-shaped part 31 is set to a value enough to prevent deformation of a side plate 33 disposed adjacently to the bottom part 24 even when the bottom part 2 is deformed by a pressure generated by the impeller 32. Thus, the influence of the bottom part 24 is prevented from being exercised on weld parts 33a-33d between the impeller 32 and the side plate 33.;COPYRIGHT: (C)1994,JPO