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Patent 2802876 Summary

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Claims and Abstract availability

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(12) Patent: (11) CA 2802876
(54) English Title: TOWER-STYLE DOUBLE CYLINDER HYDRAULIC OIL PUMPING UNIT
(54) French Title: MODULE DE POMPAGE DE PETROLE HYDRAULIQUE A DOUBLE CYLINDRE DE STYLE TOUR
Status: Expired and beyond the Period of Reversal
Bibliographic Data
(51) International Patent Classification (IPC):
  • F04B 47/02 (2006.01)
  • E21B 43/12 (2006.01)
(72) Inventors :
  • ZHOU, SHUANG (Canada)
  • ZHOU, GUOFENG (Canada)
(73) Owners :
  • VAN PACIFIC CONSULTING LTD.
  • SHUANG ZHOU
(71) Applicants :
  • VAN PACIFIC CONSULTING LTD. (Canada)
  • SHUANG ZHOU (Canada)
(74) Agent: NEXUS LAW GROUP LLP
(74) Associate agent:
(45) Issued: 2015-05-12
(22) Filed Date: 2012-12-10
(41) Open to Public Inspection: 2014-02-02
Examination requested: 2012-11-19
Availability of licence: N/A
Dedicated to the Public: N/A
(25) Language of filing: English

Patent Cooperation Treaty (PCT): No

(30) Application Priority Data:
Application No. Country/Territory Date
201220379013.0 (China) 2012-08-02

Abstracts

English Abstract


A tower-style double cylinder hydraulic pumping unit has a first cylinder and
a
second cylinder. The first cylinder is connected by a cable linkage to the
sucker rod, such
that expansion of the first cylinder serves to lift a sucker rod. The second
cylinder is
connected by a cable linkage to a counterweight, such that expansion of the
second cylinder
serves to lift the counterweight. A pump alternatively pumps hydraulic fluid
into the first
cylinder and then the second cylinder to create reciprocating movement of the
sucker rod and
the counterweight. When the first cylinder expands the second cylinder
retracts to pull the
sucker rod up, while the counterweight moves down. When the second cylinder
expands the
first cylinder retracts to pull the counterweight up, while the sucker rod
moves down.


French Abstract

Une unité de pompage hydraulique à double cylindre de type tour comporte un premier et un deuxième cylindre. Le premier cylindre est relié par une timonerie à câbles à une tige de pompage, de manière que la dilatation du premier cylindre serve à soulever la tige de pompage. Le deuxième cylindre est relié par une timonerie à câbles à un contrepoids, de manière que la dilatation du deuxième cylindre serve à soulever le contrepoids. Une pompe pompe du fluide hydraulique de manière alternée dans le premier cylindre, puis dans le deuxième cylindre pour créer un mouvement de va-et-vient de la tige de pompage et du contrepoids. Lorsque le premier cylindre se dilate, le deuxième cylindre se rétracte pour tirer la tige de pompage vers le haut, alors que le contrepoids se déplace vers le bas. Lorsque le deuxième cylindre se dilate, le premier cylindre se rétracte pour tirer le contrepoids vers le haut, alors que la tige de pompage se déplace vers le bas.

Claims

Note: Claims are shown in the official language in which they were submitted.


9
What is Claimed is:
1. A tower-style double cylinder hydraulic pumping unit, comprising:
a main frame;
a sucker rod connection positioned on a first side of the main frame, whereby
a
sucker rod is connected;
a counterweight positioned on a second side of the main frame, opposite the
first
side;
a cable linkage between the sucker rod connection and the counterweight, the
cable
linkages being supported by pulley groups on the main frame;
a first cylinder that expands and retracts and is supported by the main frame,
the first
cylinder connected to the cable linkage such that expansion of the first
cylinder serves to lift
the sucker rod;
a second cylinder that expands and retracts and is supported by the main
frame, the
second cylinder being connected to the cable linkage such that expansion of
the second
cylinder serves to lift the counterweight;
a pump connected to a hydraulic fluid reservoir and by piping to the first
cylinder and
the second cylinder, the pump alternatively pumping hydraulic fluid from the
hydraulic fluid
reservoir into the first cylinder and then the second cylinder to create
reciprocating
movement of the sucker rod and the counterweight;
such that when hydraulic fluid is pumped into the first cylinder, the first
cylinder
expands and at the same time hydraulic fluid is expelled out of the second
cylinder causing
the second cylinder to retract, this movement being transmitted through the
cable linkage to
pull the sucker rod up, while the counterweight moves down;
such that when hydraulic fluid is pumped into the second cylinder, the second
cylinder expands and at the same time hydraulic fluid is expelled out of the
first cylinder
causing the first cylinder to retract, this movement being transmitted through
the cable
linkage to pull the counterweight up, while the sucker rod moves down.

Description

Note: Descriptions are shown in the official language in which they were submitted.


CA 02802876 2014-10-06
TITLE
[0001] Tower-Style Double Cylinder Hydraulic Pumping Unit
FIELD
[0002] There is described a hydraulic pumping unit for use in oil recovery.
BACKGROUND
[0003] The basic framework of modern oil pumping equipment is a "3 piece"
model,
which includes an oil pump, a sucker rod and an electronic motor. The
traditional walking-
beam pumping unit, was developed using this model and has been in use
throughout the
world for several decades.
[0004] As the oil level of developed oil fields declines, and deeper,
higher density oil
fields are being exploited, oil pumping units need to reach deeper into the
well, and with
stronger lift forces. Therefore, the traditional walking-beam pumping unit has
been facing
declining efficiency and thus, is no longer fit for oil production in many
cases.
[0005] Most existing oil pumps have maximum stroke of over 5 meters.
However, under
the current "3 piece" model, only part of the stroke - about 3 meters - is
frequently used. This
results in wear and tear only occurring in this 3 meter area, and requires
more frequent
inspection and replacement than should be necessary, while the rest of the
capacity is wasted.
The useful life of a sucker rod is decided by the number of strokes. The less
the number of
strokes in a given time, the longer the sucker rod is capable of functioning.
What is required
is an oil pumping unit that satisfies the following three criteria: long
stroke, low stroke
frequency, and stronger lift.
SUMMARY
[0006] There is provided a tower-style double cylinder hydraulic pumping
unit which
has a main frame. A sucker rod connection is positioned on a first side of the
main frame,
whereby a sucker rod is connected. A counterweight is positioned on a second
side of the
main frame, opposite the first side. A cable linkage is provided between the
sucker rod
connection and the counterweight. The cable linkages are supported by pulley
groups on the
main frame. A first cylinder is provide that expands and retracts and is
supported by the
main frame. The first cylinder is connected to the cable linkage such that
expansion of the

CA 02802876 2014-10-06
2
first cylinder serves to lift the sucker rod. A second cylinder is provided
that expands and
retracts and is supported by the main frame. The second cylinder is connected
to the cable
linkage such that expansion of the second cylinder serves to lift the
counterweight. A pump
is connected to a hydraulic fluid reservoir and by piping to the first
cylinder and the second
cylinder. The pump alternatively pumps hydraulic fluid from the hydraulic
fluid reservoir
into the first cylinder and then the second cylinder to create reciprocating
movement of the
sucker rod and the counterweight. When hydraulic fluid is pumped into the
first cylinder, the
first cylinder expands and at the same time hydraulic fluid is expelled out of
the second
cylinder causing the second cylinder to retract. This movement is transmitted
through the
cable linkage to pull the sucker rod up, while the counterweight moves down.
When
hydraulic fluid is pumped into the second cylinder, the second cylinder
expands and at the
same time hydraulic fluid is expelled out of the first cylinder causing the
first cylinder to
retract. This movement is transmitted through the cable linkage to pull the
counterweight up,
while the sucker rod moves down.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] These and other features will become more apparent from the
following
description in which reference is made to the appended drawings, the drawings
are for the
purpose of illustration only and are not intended to be in any way limiting,
wherein:
[0008] FIG. 1 is a side elevation view of a frame section of a tower-style
double cylinder
hydraulic pumping unit.
[0009] FIG. 2 is a schematic diagram of a hydraulic section of the tower-
style double
cylinder hydraulic pumping unit of FIG. 1.
DETAILED DESCRIPTION
[0010] A tower-style double cylinder hydraulic pumping unit will now be
described with
reference to FIG. 1 and FIG. 2.
Structure and Relationship of Parts:
[0011] Referring to FIG. 1, the Unit's Frame includes:
1) Frame; the entire frame includes a main frame (1) and two
triangular frames (12);

CA 02802876 2014-10-06
3
2) Two oil Cylinders (See (17) and (18) in FIG. 2) with tanks;
3) Movable pulley groups, including movable supporting frames and rail;
4) Piston rod;
5) Oxbow (Beam Hanger);
6) Counterweight fixed pulley groups;
7) Rim fixed (pulling) pulley group;
8) lid;
9) Sucker Rod pulling ropes (steel wire);
10) Top fixed pulley groups;
11) Counterweight pulling ropes (steel wire);
12) Triangular frames;
13) Counterweight steel wire ropes;
14) Fixed supporting frame;
15) Pulley fixer frame;
16) Counterweight.
[0012] Two oil Cylinders are mounted vertically on each side of the main
frame (1).
Each oil Cylinder includes a cylinder tank (2) with piston, and a piston rod
(4). The pistons
and cylinder tanks move in opposite directions, which enables the cylinder
tanks to move
downward when stretching out (oil comes in) and pushing the rod (4) upward, or
upward
when retracting (oil pumped out).
[0013] The movable pulley groups (3) are attached to the bottom of each
oil cylinder
tank (2) and moves with the tanks; the other end of both piston rods (4) are
fixed to the
bottom of the Lid (8), which is mounted at the upper centre of the Main Frame
(1). On the
other (upper) side of the Lid (8) are installed two Top fixed pulley groups
(10). Two
triangular frames (12) are mounted at both sides of the top of the Main Frame
(1), and are
connected to the Main Frame (1) with pivot pins. Another three pulley groups
(6) and (7) are
installed on the upper surface of each triangular frame (12), including two
Counterweight
fixed pulley groups (6), and a Rim fixed (pulling) pulley group (7) in the
middle.

CA 02802876 2014-10-06
4
[0014] Counterweight steel wire rope (13) connects the Counterweight (16)
at its right
end with the Oxbow (Beam Hanger) (5), by going up around Counterweight fixed
pulley
group (6) on the right triangle frame (12), turning left around the other
Counterweight fixed
pulley group (6) on the left triangle frame (12) and going down to the Oxbow
(S).
[0015] The Sucker Rod pulling rope (9) connects the Oxbow (5) on its left
end to the
Pulley fixer frame (15) by going up around the Rim fixed (pulling) pulley
group (7) on the
left triangle frame (12), turning right around the left Top fixed pulley group
(10), then
turning down around the left Movable pulley group (3), coming back up to the
Pulley fixer
frame (15).
[0016] The Counterweight pulling rope (11) connects the Counterweight
(16) at its right
end to the Pulley fixer frame (15) by going up around the Rim fixed (pulling)
pulley group
(7) on the right triangle frame (12), turning left around the right Top fixed
pulley group (10),
going down around the right Movable pulley group (3), coming back up to the
Pulley fixer
frame (15).
[0017] Oil Cylinder A (17) and oil Cylinder B (18) are vertically mounted
on both sides
of the Main Frame. Pistons and cylinders move in opposite directions.
Cylinders make
telescopic movement, downward when stretching out (oil comes in) and upward
when
retracting (oil pumped out). Both cylinders alternately stretch and retract
and the pumping
action is realized through traction of the piston rods and movements of the
counterweight
basket, pulled with steel wire ropes.
[0018] In the rising process of the sucker rod, the sucker rod is lifted
through thrust of
Oil Cylinder A (17) on the right and potential energy of the counterweight
basket; in the
declining process of the sucker rod, the counterweight basket is lifted
through thrust of oil
cylinder B (18) on the left and potential energy of the sucker rod to save the
counter potential
energy required for the next lifting of the sucker rod. The design balances
the sucker rod with
the weight of the counterweight basket, so that the cylinders' working loads
are constant,
therefore the driving electronic motor could work with stable current through
the pumping
cycle and achieve efficiency.

CA 02802876 2014-10-06
[0019] Referring to FIG. 2, the Unit's hydraulic oil pumping system
includes:
15) Right oil Cylinder (A);
16) Left oil Cylinder (B);
5 17) 4 way switching valve;
18) Overflow/unloading controller;
19) Oil pump (connected to the electronic motor);
20) Switch sensor A;
21) Switch sensor B.
[0020] The hydraulic pumping system is installed partially outside,
partially onto the
main frame, and drives the movement of both cylinders by pumping in high
pressure liquid
oil (hydraulic oil).
[0021] The hydraulic pumping system is an open hydraulic circuiting system.
An
electronic motor drives the oil pump to spin, pumping out high pressure
hydraulic oil. The
high pressure hydraulic oil flows through the 4 way switching valve (19) into
oil cylinder B
(18) on the left side of the Main Frame(the process is the same if starts with
oil Cylinder A
on the right, (17)). The tank of oil Cylinder B (18) moves downward to switch
sensor B (23),
which, upon sensing the tank in a certain range, sends signal to switch the 4
way switching
valve. Upon switching the tank of the other oil cylinder, Cylinder A (17),
starts to move
downward to switch sensor A (22). Switch sensor A (22) then sends signal to
switch the 4
way switching valve again when the tank of Cylinder A (17) reaches its range,
thus
completes a circle. The overflow/unloading controller (20) protects both
cylinders during
movements, while also release the load during launching phase and when the oil
pump is
spinning but the cylinders are stopped.
[0022] Referring to FIG. 1, Main Frame (1) is a welded structure using
square cut hollow
steel beams; Triangle frames are welded using square cut hollow steel beams or
channel
beams. Lid (8), Oxbow (5), Fixed supporting frame (14) and Pulley fixer frame
(15),
together with the bases of various pulley groups are all made by steel slates,
using welding
techniques; Counterweight (16) is welded mainly using rectangle steel beams.
[0023] When installing, use anchor slate to fix Main Frame (1) to a
concrete ground, use
steel pivot pins to connect the two triangle frames (12) to both sides of the
upper Main

CA 02802876 2014-10-06
6
Frame, and then connect 3 pulley groups - two counterweight pulley groups(6)
and one Rim
fixed pulley group (7) onto the upper surface of each triangular frame (12).
The two
Counterweight fixed pulley groups (6) are installed on both sides of the
triangular frames,
with the Rim fixed (pulling) pulley group (7) sits between (6). The Lid (8) is
screwed to the
centre of the top of the Main Frame (1). Two Top fixed pulley groups (10) are
installed,
symmetrically, on both sides of the upper surface of the Lid (8). The two oil
Cylinders (17)
and (18) are inside the Main Frame (1), with a steel rod fixed on top of each;
the other end of
the Piston rods (4) are fixed, symmetrically, to the bottom of the Lid (8). A
movable pulley
group (3) is installed to the bottom of each of the oil Cylinder tanks.
[0024] Counterweight steel wire ropes (13) and two steel pulling ropes
(9) and (11) are
used to connect Oxbow (5) all the way to Counterweight basket (16). The oil
pump station is
outside the Main Frame, using two oil pipes to connect to the two oil
Cylinders (17) and
(18). Hydraulic oil is then pumped into oil Cylinders A (17) and B (18)
alternatively, driving
them to move downward, which in turn pulling Oxbow (S) (connected to the
sucker rod) or
the Counter weight basket (16) to move up, though the connection of Piston
rods (4) and
steel pulling ropes (9) and (11). Due to the design of two movable pulley
groups, the travel
distance of Oxbow (5) or the Counterweight basket (16) are twice of the travel
distance of
the oil Cylinder tanks. The setup of two switch sensors (22) and (23) decides
the maximum
travelling distance and timing to switch between oil Cylinders A (17) and B
(18).
Operation:
[0025] Referring to FIG. 2, when the 4 way switching valve (19) is at
neutral position,
the oil intake of both oil Cylinders (17) and (18) are closed, the two Piston
Rods (4) are
stationary, and the sucker rod could stay at random position. When the 4 way
switching
valve is turned left, hydraulic oil flows into the left oil Cylinder (18),
pushing its tank (2)
downward; at the same time the right oil Cylinder (17) expels oil out,
retracting its tank
upward, thus, through the steel pulling ropes, pulls the Oxbow (15) (connected
to the sucker
rod) up while the Counterweight basket (16) moves down. When the 4 way
switching valve
is turned right, hydraulic oil flows into the right oil Cylinder (17), pushing
its tank (2)
downward; at the same time the left oil Cylinder (18) expels oil out,
retracting its tank
upward, thus, through the steel pulling ropes, pulls the Counterweight basket
(16) up while

CA 02802876 2014-10-06
7
the Oxbow (15) (connected to the sucker rod) moves down. When either tank of
the oil
Cylinders moves down close enough to the switch sensors (22) or (23), the
switch sensor
sends signal to the 4 way switching valve (19) to switch the direction.
Advantages:
[0026] The features of this new Tower-style Double Cylinder Hydraulic
Pumping Unit,
which gives it significant advantages over existing oil pumping designs or
technologies,
which include:
1. Larger hanging strength (over 2801(N); long strike distance (over 8m);
lower
strike frequency(minimum frequency lower than 0.5/minute); strike
distance/frequency could
be adjusted to suit different needs;
2. Triangle frames could be switched to sideways and make room for drilling
wells,
therefore no need to uninstall/reinstall the machine when adjusting the
location in a small
range;
3. Could be easily equalized, current balance could be adjusted over 95%;
4. Electric motor runs consistently in the same direction;
positive/negative cycle
affords similar loads, therefore the electronic motor's load is stable;
5. The Electronic motor's required capacity is about 1/3 of that is
required for
current conventional pumping units;
6. Lighter, smaller, easier for transportation and installation;
7. Simply structure that is durable, reliable and easy for
maintenance.
[0027] In this patent document, the word "comprising" is used in its non-
limiting sense
to mean that items following the word are included, but items not specifically
mentioned are
not excluded. A reference to an element by the indefinite article "a" does not
exclude the
possibility that more than one of the element is present, unless the context
clearly requires
that there be one and only one of the elements.
[0028] The scope of the claims should not be limited by the illustrated
embodiments set
forth as examples, but should be given the broadest interpretation consistent
with a purposive

CA 02802876 2014-10-06
8
construction of the claims in view of the description as a whole.

Representative Drawing

Sorry, the representative drawing for patent document number 2802876 was not found.

Administrative Status

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Event History

Description Date
Revocation of Agent Requirements Determined Compliant 2022-01-12
Appointment of Agent Requirements Determined Compliant 2022-01-12
Time Limit for Reversal Expired 2019-12-10
Common Representative Appointed 2019-10-30
Common Representative Appointed 2019-10-30
Letter Sent 2018-12-10
Grant by Issuance 2015-05-12
Inactive: Cover page published 2015-05-11
Pre-grant 2015-02-11
Inactive: Final fee received 2015-02-11
Notice of Allowance is Issued 2015-01-22
Letter Sent 2015-01-22
Notice of Allowance is Issued 2015-01-22
Inactive: Q2 passed 2015-01-15
Inactive: Approved for allowance (AFA) 2015-01-15
Amendment Received - Voluntary Amendment 2014-10-06
Inactive: Filing certificate - RFE (bilingual) 2014-04-25
Correct Applicant Requirements Determined Compliant 2014-04-25
Inactive: S.30(2) Rules - Examiner requisition 2014-04-14
Inactive: Report - QC passed 2014-03-31
Inactive: Cover page published 2014-02-02
Application Published (Open to Public Inspection) 2014-02-02
Inactive: Applicant deleted 2013-12-03
Inactive: Applicant deleted 2013-12-03
Inactive: Applicant deleted 2013-12-03
Inactive: Acknowledgment of s.8 Act correction 2013-12-03
Correction Request for a Granted Patent 2013-11-19
Correction Request for a Granted Patent 2013-11-18
Inactive: Office letter 2013-08-22
Change of Address Requirements Determined Compliant 2013-08-06
Appointment of Agent Requirements Determined Compliant 2013-08-06
Revocation of Agent Requirements Determined Compliant 2013-08-06
Inactive: Office letter 2013-08-06
Inactive: Office letter 2013-08-06
Correction Request for a Granted Patent 2013-07-23
Revocation of Agent Request 2013-07-23
Appointment of Agent Request 2013-07-23
Change of Address or Method of Correspondence Request Received 2013-07-10
Inactive: First IPC assigned 2013-03-06
Inactive: IPC assigned 2013-03-06
Inactive: IPC assigned 2013-02-27
Inactive: Office letter 2013-02-12
Reinstatement Requirements Deemed Compliant for All Abandonment Reasons 2013-02-12
Letter Sent 2013-02-04
Application Received - Regular National 2013-02-04
Inactive: Filing certificate - RFE (English) 2013-02-04
Filing Requirements Determined Compliant 2013-02-04
Inactive: Office letter 2013-02-04
Small Entity Declaration Determined Compliant 2012-12-10
All Requirements for Examination Determined Compliant 2012-11-19
Request for Examination Requirements Determined Compliant 2012-11-19
Small Entity Declaration Determined Compliant 2012-11-19

Abandonment History

There is no abandonment history.

Maintenance Fee

The last payment was received on 2014-08-26

Note : If the full payment has not been received on or before the date indicated, a further fee may be required which may be one of the following

  • the reinstatement fee;
  • the late payment fee; or
  • additional fee to reverse deemed expiry.

Please refer to the CIPO Patent Fees web page to see all current fee amounts.

Fee History

Fee Type Anniversary Year Due Date Paid Date
Request for examination - small 2012-11-19
Application fee - small 2012-11-19
2013-11-18
MF (application, 2nd anniv.) - small 02 2014-12-10 2014-08-26
Final fee - small 2015-02-11
MF (patent, 3rd anniv.) - small 2015-12-10 2015-11-12
MF (patent, 4th anniv.) - small 2016-12-12 2016-12-12
MF (patent, 5th anniv.) - small 2017-12-11 2017-12-11
Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
VAN PACIFIC CONSULTING LTD.
SHUANG ZHOU
Past Owners on Record
GUOFENG ZHOU
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
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Document
Description 
Date
(yyyy-mm-dd) 
Number of pages   Size of Image (KB) 
Drawings 2014-10-06 2 97
Cover Page 2015-04-22 1 32
Description 2012-12-10 9 308
Abstract 2012-12-10 1 36
Claims 2012-12-10 3 90
Drawings 2012-12-10 2 38
Cover Page 2014-01-13 1 47
Description 2014-10-06 8 307
Abstract 2014-10-06 1 18
Claims 2014-10-06 1 38
Acknowledgement of Request for Examination 2013-02-04 1 176
Filing Certificate (English) 2013-02-04 1 156
Filing Certificate 2014-04-25 1 205
Reminder of maintenance fee due 2014-08-12 1 112
Commissioner's Notice - Application Found Allowable 2015-01-22 1 162
Maintenance Fee Notice 2019-01-21 1 182
Maintenance Fee Notice 2019-01-21 1 181
Correspondence 2013-02-04 1 18
Correspondence 2013-02-12 1 11
Correspondence 2013-02-12 2 59
Correspondence 2013-07-10 1 29
Correspondence 2013-07-23 11 537
Correspondence 2013-08-06 1 17
Correspondence 2013-08-06 1 19
Correspondence 2013-08-22 2 66
Correspondence 2013-11-19 2 39
Correspondence 2013-11-18 5 167
Correspondence 2013-12-02 3 95
Fees 2014-08-26 1 25
Correspondence 2015-02-11 1 37
Fees 2015-11-12 1 25
Fees 2016-12-12 1 25
Maintenance fee payment 2017-12-11 1 25