OIL WELL PUMPING UNIT

MODULE DE POMPAGE POUR PUITS DE PETROLE

English Abstract

An oil well pumping unit is provided. The oil well pumping unit includes lift
and
pump/compressor tubing columns, plunger pumps, a packer, and combined
assemblies
installed in upper and lower portions of a casing.

Claims

What is claimed is:
1. An oil well pumping unit designed for simultaneous dual production from two
formations
in a well, the unit comprising:
lift and pump/compressor tubing columns;
plunger pumps having suction and discharge valves located in a casing and a
linear
motor installed between said suction and discharge valves;
a packer having an annular space between the casing and the linear motor;
combined assemblies installed in upper and lower portions of the casing, the
upper
portion having built-in valves, an access port for directing the upward flow
of the oil
well fluid in the sub-packer zone from the annular space towards the lift
column,
and an opening for cable entry installation, the lower portion having a
pressure-
tight connection with the casing and the pump/compressor tubing column.
2. The oil well pumping unit of claim 1, further comprising a gland seal
installed between
the lower combination assembly and the jacket.
-4-

Description

CA 02843528 2014-02-20
OIL WELL PUMPING UNIT
FIELD
[0001] This design relates to the oil industry, in particular to machines
for oil production
equipped with oil well pumps.
BACKGROUND
[0002] An oil well pumping unit for simultaneous dual production from two
formations of a
well is known. It includes lift and pump/compressor tubing columns, plunger
pumps with suction
and discharge valves located in the casing, and a linear motor which is
installed between them
(FR2385911A, 27.10.1978).
[0003] The disadvantages of the currently known unit are its complex
design, the
impossibility of separating the flows of oil well fluid produced in sub-packer
and supra-packer
zones, as well as the impossibility of complying with the cooling mode of its
linear motor.
SUMMARY
[0004] The unit is designed for use in the oil industry for producing oil
by means of oil-well
pumps with simultaneous dual production from two formations of one well. The
unit is for
simultaneous dual production from two formations in a well includes lift and
pump/compressor
tubing columns and plunger pumps, suction and discharge valves located in the
casing. A liner
motor is installed between the pumps. The unit is fitted with a packer. An
annular space is
situated between the casing and the motor. Combined assemblies are installed
in the upper and
lower portions of the casing; the upper one includes built-in valves, an
access port for directing
the upward flow of oil well fluid in the sub-packer zone from the annular
space to the lift column,
and a port for cable entry installation. The lower assembly has a pressure-
tight connection with
the casing and pump/compressor tubing column. The design is simplified,
reliability is
increased, and the flow separation of oil well fluid from the sub-packer and
supra-packer zones
is ensured.
[0005] The objective put forward in the present invention is to simplify
the design, increase
its reliability, and simultaneously ensure the flow separation of oil well
fluid in the sub-packer
and supra-packer zones.
-1-

CA 02843528 2014-02-20
BRIEF DESCRIPTION OF THE DRAWING
[0006] Reference will now be made, by way of example only, to the
accompanying drawings
in which:
[0007] Figure 1 is a cross sectional view of a unit according to an
embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0008] The indicated objective and the technical result are achieved
because the oil well
pumping unit, which is designed for simultaneous dual production from two
formations in a well
and which includes lift and pump/compressor tubing columns, plunger pumps with
suction and
discharge valves located in the casing, and a linear motor installed between
them, is fitted with
a packer in accordance with the invention, and there is an annular space
between the casing
and the linear motor. At the same time combined assemblies are installed in
the upper and
lower portions of the casing; the upper one includes built-in valves, an
access port for directing
the upward flow of the oil well fluid in the sub-packer zone from the annular
space towards the
lift column, as well as an opening for cable entry installation, and the lower
one has a pressure-
tight connection with the casing and the pump/compressor tubing column.
[0009] A packing seal is installed between the lower combined assembly and
the casing.
[0010] Referring to Figure 1, the pumping unit for simultaneous dual
production from two
formations in a well includes lift 1,2 and pump/compressor 3,4 tubing columns
and upper
plunger pump 6 and lower plunger pump 7 located in casing 5, suction 8,9 and
discharge 10,11
valves. Linear motor 12 is installed between the pumps. The unit is fitted
with a packer 13. The
annular space 14 is situated between casing 5 and linear motor 12. The
combined assemblies
15 and 16 are installed in the upper and lower portions of casing 5. The upper
assembly 15
includes built-in suction 8 and discharge 10 valves. An access port 17 is
provided for directing
the upward flow of the oil well fluid in the sub-packer zone from the annular
space 14 to the lift
column. Also the assembly includes a cable entry 18 to connect the cable
extension 19 of the
motor with cable line 20.
[0011] The upper combined assembly 15 is designed for separating the flows
of oil well fluid
which are produced in sub-packer zone 21 and supra-packer zone 22. The lower
combined
assembly 16 has a pressure-tight connection with casing 5 and pump/compressor
tubing
column 4 and is fitted with access port 23.
-2-

CA 02843528 2014-02-20
[0012] The unit operates in a following manner.
[0013] The electrical power from the control station is supplied to the
linear motor 12 along
cable line 20 via cable entry 18 and by way of cable extension 19. Electrical
power is converted
by the linear motor 12 into mechanical energy in the form of reciprocal
movement of a rod,
which connects the motor with the pump plungers.
[0014] During the motor rod stroke the movement is transferred to the upper
plunger pump
6 via the upper shaft 24 and to the lower plunger pump 7 via lower shaft 25
and the line of rods
26, which by design are connected to the linear motor casing by the
pump/compressor tubing
columns 3 and 4. When the motor rod stroke moves downward, the lower plunger
pump 7
discharges oil well fluid via valve 11 and access port 23 into annular space
14, and upper
plunger pump 6 sucks oil well fluid via valve 8 from the casing annulus of
supra-packer zone 22.
At the same time valves 9 and 10 are closed. Oil well fluid from the lower
plunger pump 7, while
passing along annular space 14 via access port 16 enters annular space 27
between the lift
columns and then by way of the lift column of pump/compressor tubing column 1
it goes to the
wellhead.
[0015] During the rod stroke upper plunger pump 6 discharges oil well fluid
via valve 10 into
annular space 28 of lift column 2. And lower plunger pump 7 sucks oil well
fluid via valve 9 from
sub-packer zone 21. At the same time valves 8 and 11 are closed. From the
upper plunger
pump oil well fluid enters annular space 28, and then by way of the lift
column of
pump/compressor tubing column 2 it goes to the wellhead.
[0016] The unit as described can be used for the production of oil from
wells with casing
strings of a diameter not less than 168 mm and permits the development of two
production
horizons of one well at the same time using one linear motor.
[0017] While specific embodiments have been described and illustrated, such
embodiments
should be considered illustrative only and should not serve to limit the
accompanying claims.
-3-

Representative Drawing