Electric off-axis opposing piston linear actuator pumping system

Patent metadata

Field	Value
Publication number	US-2021222682-A1
Application number	US-202117153182-A
Country	US
Kind code	A1
Filing date	Jan 20, 2021
Priority date	Jan 21, 2020
Publication date	Jul 22, 2021
Grant date	—

Abstract

A pumping system for fracking fluid is designed to provide nearly constant flow rate. The pumping system includes a set of linear actuator pumping units, each driven by an electric motor. Each pumping unit includes a first set of pumping chambers that expel fluid when the linear actuator is moving in a first direction and a second set of pumping chambers that expel fluid when the linear actuator is moving in an opposite direction. The speeds of the actuators are coordinated such that a total flow rate of the pumping system is substantially constant.

First claim

What is claimed is:

1 . A pumping unit comprising:
a housing defining a central cavity and a plurality of bores radially around the central cavity; a shaft extending through the central cavity; a linear actuator within the central cavity configured to translate the shaft; a first set of pistons extending from a first subset of the bores and linked to a first end of the shaft; and a second set of pistons extending from a second subset of the bores and linked to a second end of the shaft, the second end of the shaft on an opposite side of the housing from the first end of the shaft.

2 . The pumping unit of claim 1 further comprising a plurality of valve units, each valve unit fixed the housing at an end of a bore opposite a corresponding piston.

3 . The pumping unit of claim 1 wherein:
the first set of pistons is linked to the first end of the shaft by a first arm; and
the second set of pistons is linked to the second end of the shaft by a second arm.

4 . The pumping unit of claim 3 further comprising:
a first bellows extending between the housing and the first arm, surrounding the shaft; and
a second bellows extending between the housing and the second arm, surrounding the shaft, the first and second bellows sealing the central cavity.

5 . The pumping unit of claim 1 wherein the housing is machined as a single unit.

6 . A pumping system comprising:
a plurtality of pumping units according to claim 1 ; and a controller configured to vary a flow rate of each of the pumping units such that a total flow rate is substantially constant.

7 . The pumping system of claim 6 wherein the flow rate of each pumping unit includes a series of alternating increasing phases and decreasing phases, each increasing phase coordinated with a decreasing phase of another of the pumping units, each decreasing phase coordinated with an increasing phase of another of the pumping units.

8 . The pumping system of claim 7 wherein each decreasing phase is separated from the previous increasing phase by a constant flow phase.

Assignees

• Schaeffler Technologies Ag

Inventors

• Vazquez Andre
• Hooker Craig
• Conlin Michael

Classifications

• F04B9/02

  the means being mechanical · CPC title

• F04B23/06 Primary

  the pumps being all of reciprocating positive-displacement type · CPC title

• F04B1/128

  Driving means · CPC title

• F04B17/03 Primary

  driven by electric motors · CPC title

• E21B43/2607

  Surface equipment specially adapted for fracturing operations · CPC title