Lawrence Pumps Inc.

Flowserve Management Company

Dale B Andrews

Paul E Griggs

Michael C Witzgall

D Paul Russell

A bearing and seal assembly for supporting and sealing a terminating outboard end of an impeller shaft in a centrifugal pump such as a between-bearings pump includes only one seal but provides advantages typical of a dual-seal assembly, including barrier fluid protection against seal damage caused by abrasive slurries, and protection against leaking of toxic process fluid to atmosphere. A bearing housing sealed to the pump's pressure casing encloses the seal, bearing, and terminating impeller shaft end. Leakage of process fluid past the seal is prevented by a lubricating, pressurized, cooled barrier fluid which is circulated through the bearing housing by an external pump and/or by an internal, shaft-driven impeller. Because the impeller shaft terminates within the bearing housing and does not penetrate to atmosphere, the barrier fluid is contained within the bearing housing and a second seal is not required.

Fully enclosed seal and bearing assembly for between-bearing pumps

A multistage, centrifugal partial emissions pump with a first stage impeller, a final stage impeller, a first stage casing liner, one or more first stage discharge nozzles, a final stage casing liner, one or more final stage discharge nozzles, an interstage delivery channel liner, one or more delivery channels, and an outer pressure shell wherein the first stage casing liner and the final stage casing liner are connected by one or more fluid channels integral within a delivery channel liner, that follow an arced path directed predominantly radially inward within the interstage delivery channel liner, and the sum of the cross sectional areas of all delivery channels taken on a radial plane intersecting the delivery channels is less than the sum of cross sectional areas of the non-channel areas within the boundaries of the channels.

Multistage slurry pump

An open face cooling system for a motorized, impeller-type, submersible pump operated in a host fluid ladened with solids, comprising an inlet in the pump housing close to the impeller and away from the axis of the pump into which fluid is forced by pump pressure, the inlet arranged so the impeller vanes sweep its face with a shearing motion that reduces the size of any solids present there until they are small enough to enter the inlet with the fluid flow, the materials ladened fluid flowing hence through a coolant conduit, out of a tangentially configured nozzle into a rotational flow around the inside of an open face toroidal section, and hence inward through an adjoined, inward extending distribution section configured co-axially around and above the motor, to be discharged upon the motor.

Open face cooling system for submersible motor

A canned motor has an L/Dratio of less than 50, with one bearing on one end of the rotor assembly configured to resist longitudinal displacement of the rotor as by an axial shaft load, and another bearing on the other end of the rotor assembly configured to allow limited longitudinal displacement of the rotor assembly within the bearing as from thermal expansion, lengthwise adjustment or pressure from an axial shaft load. The rotor assembly may include a center shaft coaxially extended through a hollow shaft, with rotor windings mounted on the hollow shaft, with the first bearing positioned on one end of the hollow shaft and the second bearing mounted on the second hollow shaft end. A cap and nut assembly on the second hollow shaft end, into which the rotor shaft end is threaded, provides for adjusting the effective rotor shaft length protruding from the motor, and for replacement of the rotor shaft within the hollow shaft without removing the rotor assembly from motor.

Low speed canned motor

A submersible electric motor driven pump includes a motor chamber and a pump chamber separated by a seal chamber. Inboard and outboard shaft seals immersed in an oil buffer fluid within the seal chamber restrict the flow of liquid from the seal chamber into the pump and motor chambers. An integral or externally mounted pre-pressurized buffer fluid reservoir maintains a positive fluid pressure in the seal chamber relative to the external pressure at working depth, and suitable buffer fluid level within the chamber, preventing the ingress of the pumped media through the outboard seal. A unique impeller design circulates fluid within the seal chamber in the region of the outboard shaft seal, allowing continuous run dry operation when used in conjunction with an integrally cooled motor design. A cartridge shaft sleeve subassembly permits with a bearing configured between the inboard and outboard seals, facilitates maintenance.

Growing community of inventors

Derry, NH, United States of America

Dale B Andrews