Abstract:
A fluid impeller (100) for a centrifugal pump includes a hub (105) having a substantially disk-like form with a center and an edge, circular symmetry, and provosion for being rotatably driven. A first plurality of pumping vanes (110) projects substantially perpendicularly from a first surface of the hub and extends radially outwardly from a locus (210) near the center of the hub to another locus (150) near the edge of the hub. These vanes (110) provide a high pressure head with a small impeller diameter. A second plurality of separate and twisted inlet vanes (120) also projects substantially perpendicularly from the first surface of the hub and extends radially outwardly to the locus (210) near the center of the hub from another locus (220) nearer the center of the hub. The separate second plurality of vanes (120), by turning and pre-pressurizing the fluid, provides an impeller having capability of cavitation-free pumping at low net positive suction head (NPSH). A front shroud (180) can be used which partially or totally covers the first and/or second plurality of vanes.
Abstract:
A fluid impeller for applications requiring superior cavitation erosion resistance. The impeller has a body fabricated from a castable metastable austenitic steel alloy which has a chemical composition in the range according to table (I), the balance comprising iron and impurities. The preferred range is 17.5-18.5 % chromium, 0.5-0.75 % nickel, 0.45-0.55 % silicon, 0.2-0.25 % nitrogen, 15.5-16.0 % manganese and 0.1-0.12 % carbon. Quantitative testing has shown cavitation resistance of four to six times that of standard boiler feed pump materials. A method for making cavitation resistant fluid impellers is also disclosed.
Abstract:
A vent system (11) adapted to be installed on a standard container, in place of a shipping and storage plug, for use in venting the container without requiring any modification to the container. The vent system includes a knob (21) which is turnable in one direction to place the vent system in a vent closed condition, as for example for shipping the container, and turnable in the opposite direction to place the vent system in a vent open condition to permit air to be vented into the container during fluid removal. A vent housing (13) is adapted to be screwed into a threaded opening of the container (23). The knob includes a cap (15) and a ring (19) which are held together by a tamper evident seal (17). The knob is captured by the vent housing to prevent unwanted removal of the knob and to prevent unwanted access to the container. The tamper evident seal must be removed for access to the vent housing and for removal of the vent system from the container. An alternate embodiment has provisions for preventing leaking of fluid from the container through the vent system in the event the container is tipped.
Abstract:
An integrated centrifugal pump and motor is provided by an impeller disk which contains permanent magnets and functions as the rotor for a brushless DC motor. The rotor is supported by non-contacting radial bearings and is hydrodynamically balanced against any axial thrust so that there is no contact between rotating and stationary elements during operation. Since the impeller disk is also the motor rotor, there is no need for a shaft, in the ordinary sense, which would penetrate the case and, thus, require seals. The resulting pump is compact and can be operated electronically at variable speeds.
Abstract:
A decoking tool includes a valve body equipped with a pressurized fluid inlet and having a plurality of fluid passages, including drilling fluid passages extending substantially the full length of the valve body to conduct fluid to drilling nozzle sockets, and cutting fluid passages extending approximately half as far as the drilling fluid passages to conduct fluid to cutting nozzle sockets, the drilling and cutting fluid passages being disposed alternatingly on a circular locus about an axial centerline of the valve body. There are nozzles installed in the nozzle sockets. A diverter plate is interposed between the valve body and the pressurized fluid inlet and has axial fluid passages disposed on a circular path congruent with the circular locus, the disposition of the axial fluid passages being such that the passages align either with the drilling fluid passages or with the cutting fluid passages of the valve body. Means are provided for rotating the diverter plate to selectively provide fluid communication to either the drilling fluid passages or the cutting fluid passages.
Abstract:
A forced closed-loop cooling system is provided for an electric motor driven submersible pump having a motor housing (10) containing an electric motor with a rotatable motor shaft (13) extending therefrom and a pump housing (40) attached to the motor housing, the pump housing having a fluid inlet, a fluid outlet, and a pump impeller (45) mounted therein on the motor shaft. The closed-loop cooling system consists of a coolant jacket (20) surrounding the motor housing to define an annular motor cooling chamber (21) and an end plate (30) interposed between the motor housing and the pump housing to define a coolant sump (25) about the motor shaft. The coolant sump is in fluid communication with the motor cooling chamber and sealed from pumped fluid in the pump housing by the end plate. The end plate has features for enhanced heat transfer and is in contact with the pumped fluid in the pump housing for transferring heat thereto. There is also provision for forced circulation of coolant between the coolant sump and the annular motor cooling chamber.
Abstract:
An improvement in high pressure reciprocating plunger pumps is disclosed which is characterized by a small residual volume and mechanical simplicity. The plunger (65) is provided with a central bore (13) which carries fluid to or from a valve (85) located in the terminal end of the plunger (65). This valve (85) may be either an intake or discharge valve. Another valve (66) is provided with access to the pumping chamber (42). This second valve has a tapered exterior surface (87) which is adapted to press-fitting and hydraulic removal. Both valve actuation movements are co-linear with the direction of plunger travel.