CA2309545A1

CA2309545A1 - Improvement in progressive cavity pumps

Info

Publication number: CA2309545A1
Application number: CA002309545A
Authority: CA
Inventors: Eduard Grenke
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-05-25
Filing date: 2000-05-25
Publication date: 2001-11-25

Description

~,~~k~i.l,Y~~~3 ~ .ty~pi~i~f~ ~' ,r,7i ti:'3~"G~ ~~s~~~e 1 E ~a~~~~~0 ~ MAY~~a IMPROVEMENT IN PROGRESSIVE CA~Y PiS~~~
oo.a.i f~u This invention relates to pump systems used prim ,y CAy~d to t of downhole well fluids. It is capable of use in any pica ion i n'g'rii~~
pumping or forwarding of fluids.
BACKGROUND OF THIS INVENTION
A decade ago, most oil wells were operated by a downhole pump at or close to the bottom of a well, the pump being of a conventional reciprocating kind actuated by a rod string which in turn was reciprocated vertically by a pump jack.
Many of these older reciprocating pumps have been recently replaced by rotary-drive progressive cavity pumps. Such rotary pumps are particularly suited for the production of crude oil laden with sand and water.
GENERAL DESCRIPTION OF THIS INVENTION
The pump design disclosed herein also utilizes a rotating string, but incorporates certain novel features which improve the performance, reliability and durability of the installation.
GENERAL DESCRIPTION OF THE DRAWINGS
In the drawings, Figure 1 is an exploded, axial sectional view of the various components of the novel pump concept disclosed herein:~--Figure 2 is a cross-sectional view through thc~nain pumping section, taken at the line 2-2 in Figure 1;
Figure 3 is a sectional view taken at the line 2-2 in Figure 1, but showing only the inner portion; and Figure 4 is a sectional view through an upper portion of the structure, taken at the line 4-4 in Figure 1.

2 DETAILED DESCRIPTION OF THE DRAWINGS
The major components of the novel pump concept disclosed herein include a strainer 1, a pump housing 2, a pump shaft 3, a swath plate 4, pistons 5, bellows housing 6, bellows (membrane) 7, main flow valves 8, a sealing area 9, a breatherlbleed vent 10, a venting valve 11, a safety relief valve 12, a replenishing valve 13, a casing 14, a production tubing 15, a drive shaft coupling 16 and a drive string connection 17.
Operation When the pump starts up, the shaft 3, which is stabilized with bearings and sealed at 9, will rotate. Connected to the shaft 3 are two angled swath plates 4.
These swath plates, when turning, push and pull sets of pistons 5. The pistons compress hydraulic oil when they are together, and draw in hydraulic oil when they are apart. To maintain the correct atmosphere within the hydraulic oil area between pistons (i.e., pressure, quantity of oil, etc.), a set of valves is required.
The valves consist of:
1) a venting valve 11 which automatically expels any gas from the hydraulic fluid that can develop during operation due to friction, high process temperatures and air at start-up;
2) a safety relief valve 12, which protects the pump against overload which can occur if a main flow valve is plugged, jammed, etc.

3) a replenishing valve 13, which adds oil into the main hydraulic area between the pistons, which is a result- of minute leakage. The oil above the top bearings but below the top shaft seal supplies the replenishing valve.

4) a breather/bleed vent 10 is located above the top bearing and connects the oil reservoir to the atmosphere, which allows the non-pressurized oil to breath and bleed any air or gases.
When the pistons are pushed together, the bellow 7, which is located between the pistons, and which also separates the pumping media from the pumping components, bows out, creating a higher pressure in the pumping media cavity.
This cavity has an intake main valve 8 and a discharge main valve 8. These valves open and close when the bellows bow in and out, thus forwarding the pumping media. There may be from one to a number of cavities required, as determined by size. The bellows are located between the pump housing 2 and the bellow housing 6.
Support equipment is also provided. For example, a strainer 1 is connected to the bottom of the pump, and has openings which prevent large particles (which the pump cannot handle) from entering the pump.
The drive shaft coupling 16 consists of a threaded connection at one end 18, which is to be connected to the pump shaft 3. The coupling 16 has a square hole which runs axially through the entire coupling, and a tapered bore 19 on the top portion acts as a guide for the drive string connection 17.
The drive string connection 17 has, at the bottom end, a male square 20 which enters the square hole of the drive shaft coupling 16. The other end is connected to the drive string.
While one embodiment of this invention has been illustrated in the accompanying drawings and described hereinabove, it will be evident to those skilled in the art that changes and modifications may be made therein, without departing from the essence of this invention.