A%20patented%20method%20of%20designing%20a%20sucker-rod%20pumping%20system%20with%20least%20energy%20consumption,%20Patent%20

1
A patented method of designing a sucker-rod
pumping system with least energy consumption,
Patent Software IntroductionInventor Zheng
Haijin
Yangzhou Jiangsu Oilfield Ruida Petroleum
Engineering Technology Development Co.,Ltd,
China 2008.4
2
Yangzhou Jiangsu Oilfield Ruida Petroleum
Engineering Technology Development Co.,Ltd,
China Address No.1, Wenhui West Road,
Yangzhou, Jiangsu Province,
P.R.China Tel (Technical Department)
0086-514-87761146 (Marketing Department)
0086-514-87761249 Fax [phone] Email
yzruida_at_sina.com Http//www.yzruida.com
3
Contents

1. Overview
2. The theory of calculating the input power of a
   sucker-rod pumping system
3. Patented design method and its software for a
   rod pumping system with least energy consumption
4. Applying effects in oilfields Practice
5. Achievements and Market potential

4
I. Overview

• Owing to its units simpleness, convenience in
  operation and lower entire cost, sucker-rod
  pumping system is adopted in 80 oil wells all
  over the world. In these pumping wells, the
  system efficiency has been remaining low all the
  while, which results in a higher energy cost in
  oil production .

5

• According to a statistical report of former CNPC
  in 1997, CNPC had 72047 rod-pumping oil wells
  ,the average system efficiency of these wells was
  only 26.7, which meant that 73.3 of total
  energy consumption was wasted in the lifting
  process and resulted in serious mechanical wear.
  How to improve the system efficiency of pumping
  well had been focused on all along. Many
  researches had been done on mechanical innovation
  ,and had made some progress in this aspect.

6
Problem

• By careful research, we found that, besides
  mechanical factor, an important reason caused low
  efficiency was that designed system parameters
  were unreasonable (it was technically executable
  but economically unreasonable). The key reason
  for this problem was lack of a theory of
  calculating input power of sucker-rod pumping
  system ,and lack of a more economical design
  method.

7

• After several years research both on theory and
  experiments, we had founded a theory for
  calculating the input power of a sucker-rod
  pumping system ,and had set up formulas to
  calculate it. We also invented a method to design
  a rod pumping system of least input power or
  lowest annual cost for a target production.
• It has been testified by practice that, compared
  with conventional designing methods, this
  expertise has more prominent virtue in improving
  efficiency of pumping system and reducing energy
  consumption. And also, it can remarkably reduce
  operating cost by prolonging the wells TBO .

8

• Design methods go through Three stage

First stageFor the same target production ,a rod
pumping system was designed on the principle of
least investment . Second stage For the same
target production ,a rod pumping system was
designed on the principle of lightest load.
Third stage For the same target production ,a
rod pumping system is designed on the principle
of least power consumption (or least input power).
9
Contents

1. Overview
2. The theory of calculating the input power of a
   sucker-rod pumping system
3. Patented design method and its software for a
   rod pumping system with least energy consumption
4. Applying effects in oilfields Practice
5. Achievements and Market potential

10
2. The theory of calculating the input power of a
sucker-rod pumping system

• Newly classify the components of the input power
  of a sucker-rod pumping system
• Find out the influencing factors for each part of
  the input power
• Bring forward functional relations of each part
  of the input power

11
2.1 Components of the input power

• Through analyzing energy consumption in
  lifting process, we, for the first time, bring
  forward that the input power of a sucker-rod
  pumping system should be classified into five
  major parts as follows

surface mechanical loss powerPsu
down-hole viscous friction loss powerPv
Input powerPin
down-hole sliding friction loss powerPsl
solution gas expanding powerPex
Useful powerPu
12
2.2 Surface mechanical loss power
Definition Surface mechanical loss power is
the loss power of the pumping unit and the motor
in lifting process.
13
surface mechanical loss power influencing
factors ?motor power without load Pd ?loads
Fup,average load of polished rod in up
strokeFdownaverage load of polished rod in down
stroke ?stroke length s ?pumping speed
n ?influence coefficient of transmission
powerk1 ? influence coefficient of polished rod
powerk2 the functional relation
14
Cutting point
15

• 2.3 Down-hole viscous friction loss power

Definition Down-hole viscous friction loss
power is the loss power caused by the friction
occurred between liquid and the tubing , and
between liquid and rod string in lifting process.
16
Down-hole viscous friction loss power
influencing factors ?stroke , ? pumping speed
, ? tubing diameter , ? rod diameter , ? pump
setting depth , ? crude oil viscosity the
functional relation
?
uithe average liquid viscosity in the i-th
tubing segment lilength of the i-th tubing
segment m ratio of rod diameter to tubing
diameter
17
2.4 Down-hole sliding friction loss power
Definition Down-hole sliding friction loss
power is the loss power caused by the friction
occurred ,because of well deviation, between the
tubing and the rod string and between the
plunger and the pump cylinder in lifting process
???????????????????????????????????????????????
???
18
Down-hole sliding friction loss power
influencing factors ?pumping speed
and stroke ?average rod weight of
unit length ?horizontal length of
inclination section ?sliding
friction coefficient between rod and tubing the
functional relation
fksliding friction coefficient between rod and
tubing qrodaverage rod weight of unit
length Llevelhorizontal length of inclination
section
19
2.5 Solution gas expanding power
Definition In lifting process, solution gas
is continuously separated from crude oil because
of pressure drop in tubing. On the one hand ,this
causes drop of liquids energy (viz. drop of
intrinsic energy), on the other hand, the
dropping portion of intrinsic energy is
tranformed into volume expanding power which acts
on the lifting system. This kind of power is
called Solution gas expanding power.
20
Solution gas expanding power influencing
factors ?daily oil production ,?saturation
pressure , ?wellhead pressure ,?pump intake
pressure , ?solution coefficient the
functional relation
21
2.6 Influencing factors of wellhead temperature
and its functional relation From the bottom of
the well to wellhead, the temperature
corresponding to different depth is fallen in
pace with the decrease of depth. Meanwhile, oil
viscosity varies with the change of temperature.
The wellhead temperature needs to be determined
if we want to know how much the change of
temperature affects down-hole viscous friction
loss power.
22
Wellhead temperature influencing factors
?reservoir temperature. ?surface temperature.
?liquid production.?water cut . ? fluid level.
?solution gas expanding power the functional
relation
23
2.7 Influencing factors of ??iLi and its
functional relation ??iLi is the accumulated
total of multiplication of the length of each
tubing section by the liquid viscosity in the
corresponding tubing section. In order to
calculate down-hole viscous friction loss power
,the value of ??iLi must be determined.
24
??iLi influencing factors ?reservoir
temperature . ?surface temperature. ? wax
precipitation point . ?liquid production.
?water cut. ?50? degasified crude oil
viscosity the functional relation

25
2.8 Useful power
Influencing factors Daily liquid
production Liquid density Liquid lifting height
Definition Useful power is the power needed
to pump liquid production from the working
fluid level to surface in lifting process.
26

• 2.9 Calculating formulas of input power and
  system efficiency with each part of input power

Pin PuPsuPslPv-Pex
? Pu/ Pin Pu/(PuPvPsuPsl-Pex)
27
2.10 Practical verification of the theory

• In order to verify the validity of the theory
  and its adaptability to different reservoirs, we
  tested the actual system input power of 428 wells
  of 28 reservoirs in Jiangsu oilfield, and
  calculated the theoretical input powers by the
  above formulas. Results showed that theoretical
  input powers matched well with the tested input
  powers.

28
Results of the verification

• Wells tested 428
• Total input power measured 3362 Kw
• Total input power calculated 3327Kw
• Average efficiency measured 26.0
• Average efficiency calculated 26.3
• Relative error of input power1.1

29

• Through analyzing the sensitivity of 14
  variables to the input power (The 14 variables
  are detailed as follows production rate, water
  cut, working fluid level, middle depth of oil
  layer, crude oil density, gas-oil ratio (GOR),
  saturation pressure, solution coefficient,
  reservoir temperature, wax precipitation point,
  surface temperature, 50 ? degasified oil
  viscosity, oil viscosity in the oil layer,
  horizontal displacement of the well deviation) ,
  it was found that the theory of calculating the
  input power is universally applicable to 428
  wells with various production parameters in 28
  reservoirs of different geophysical parameters.

30
Measured input powers and calculated input powers
in Chen 2 block
31
Measured input powers and calculated input powers
in Fumin block
32
Measured input powers and calculated input powers
in Hua, Lian,Ji blocks
33
Measured input powers and calculated input powers
in Shanian block
34
Verification by wells of Daqing Oilfield
35

• Further verification had been made by
  applications of the new design method to about
  10000 pumping wells in oilfields of China. It
  showed that the theory of calculating input power
  is universally applicable to all wells with
  various production parameters in different
  reservoirs of different geophysical parameters.

36

• 2.11 Relationship between Influencing factors and
  losses power
• rod speed
• (stroke Pumping speed)
• Load
• No-load loss
• Crude oil viscosity
• Ratio of rod to tubing

37
Main ways to improve the efficiency

• Slow the rod speed, namely increase plunger
  diameter or improve the pumps efficiency
• Reduce the load, namely reduce the weights of
  rods and liquid
• Reduce the prime movers power under no load
• Decrease the viscosity of oil
• Increase the ratio of tubing radius to rod
  radius
• Select favorable types of beam pumping unit and
  match the prime mover rationally
• Reduce the weight of unit rod in deviated
  interval of well

38
Contradictions among various ways to improve the
efficiency
39
Under different plunger diameter , different rod
strings have distinct influence on pumping
efficiency . Under same plunger diameter and
same pumping depth, different steel grades of rod
correspond to different rod string and different
economic benefits
40
Contents

1. Overview
2. The theory of calculating the input power of a
   sucker-rod pumping system
3. Patented design method and its software for a
   rod pumping system with least energy consumption
4. Applying effects in oilfields Practice
5. Achievements and Market potential

41
3? Patented design method and its software for
a rod pumping system with least energy consumption
To overcome the contradictions mentioned above,
we invented a method of designing pumping system
parameters on principle of the lowest input power
or the lowest annual cost.
This design method has been granted patent. US
patent No US 6,640,896 B1 CN patent No ZL 99 1
09780.7
42
3.1 Design preconditions (known parameters)

• 1.production rate
• 2.water cut
• 3.working fluid level
• 4.middle depth of oil layer
• 5. oil density
• 6.gas-oil ratio (GOR)
• 7.saturation pressure
• 8.solution coefficient

9. reservoir temperature 10. wax precipitation
point 11. surface temperature 12. 50 Celsius
degasified oil viscosity 13. oil viscosity in
place 14. Relative parameters of well
deviation 15.economical parameters
43

• 3.2 Designing outcome (parameters to be designed)
  
• type of beam unit
• type of motor
• tubing diameter
• pumping depth
• plunger diameter
• steel grade of rod-string
• rod string
• stroke
• pumping speed

44
3.3. Designing procedure (soluting procedure)
In order to producing same target production
, (1) Set the selective range of different tubing
diameters, different plunger diameters, different
steel grades of rod string, different rod
strings, different strokes, different pumping
speeds, different pump depths and different types
of pumping unit.
45

• (2)Find out all the systems or combinations of
  tubing diameter, steel grade of rod-string,
  plunger diameter, pump depth, rod-string, stroke
  and pumping speed , which can produce the target
  production.
• (3) Calculate respectively the input power and
  efficiency of each system or combination by the
  calculation formulas of system input power.

46

• (4)From all the systems or combinations, choose
  the one of least input power as the result to be
  designed, which includes tubing diameter, steel
  grade of rod, plunger diameter, pump depth,
  rod-string, stroke, pumping speed, type of
  pumping unit and type of motor .

47
3.4 Difference between the patented design
method and the conventional design method

• ?Different design principles
• Same ObjectiveProduction
• Conventional methodLoad , torque and pump
  efficiency serve as constraint conditions
• New method Load, torque and input power serve as
  constraint conditions

48
?Difference in parameters required for design
Conventional method Parameters needed
Result includes 1. Liquid
production 1. type
of pumping unit 2. water cut
2. motor type 3. fluid
level
3. tubing diameter 4. gas-oil ratio (GOR)
4. pump depth 5. crude
oil viscosity 5.
plunger diameter 6. middle depth of payzone
6. steel grade

7. Rod-string
8. stroke

9. pumping speed

49
The patented design method This patented design
method needs 15 parameters as follows, while
other conventional methods merely needs 6
ones(1-6 listed). Parameters needed
Result includes
50
?Differences in system input power , efficiency
and economic virtue between the patented design
method and conventional design method
Well name Wei 2-6
Note Annual cost includes energy cost and annual
depreciation cost of tubing and rod string
51
3.5 Based on the patent method mentioned above,
a software (Pumping Star) has been developed for
designing a sucker rod pumping system

• software function
• Design a sucker-rod pumping system( or system
  parameters) with least energy consumption
• Design a sucker-rod pumping system( or system
  parameters) with least costs
• Handle the test data of pre-optimization
• Post-evaluation of the newly-designed pumping
  system

52
Data input
Main window
53
Data input
54
Data input
55
Data input
56
Data input
57
Show all design results Page 1
58
Show all design results Page 2
59
Show all design results Page 345
60
Show all design results Page 468
61
Select design result
62
Result output
63
Applying effect
64
Contents

1. Overview
2. The theory of calculating the input power of a
   sucker-rod pumping system
3. Patented design method and its software for a
   rod pumping system with least energy consumption
4. Applying effects in oilfields Practice
5. Achievements and Market potential

65

• 4.1 Effect In Jiangsu Oilfield
• From Apr. to Dec. 1999, this patented technology
  had been applied to 133 wells in Jiangsu
  oilfield. Technical supervision department
  tested these wells. The result was

9.882kW
Input Power per Well
5.806kW
24.58
44.15
System Efficiency
Power-Saving Ratio
41.25
Annual Power Saved per Well
35,706kWh
66
Effect in Jiangsu Oilfield
Input Power Contrast
67
Estimated Power-saving Ratio 42.67
Measured Power-saving Ratio 41.25
68

• 4.2 Effects in different oilfields in China

• Up to December 2006, this expertise had been
  practiced in 8569 rod-pumping wells with various
  conditions in 12 oilfields in China. Each year,
  236,000,000KWh power had been saved on average.
  The well TBO was also prolonged by about 1/3
  consequently.

69

• Applied Condition in oilfields in China

Listed as Scale Application Project for 6
successive years since 2002 Applied
wells4672 Software installed in 2007 35 sets
Liaohe Oilfield
Shengli Oilfield
Bought out the absolute implement permission of
this patent and installed 18 sets of software in
2004 Applied wells up to 2005 3321
Daqing Oilfield
Tested well 11 Promoted Wells771, up to
2005 Software installed in 2007 90 sets
70

• Effect in different oilfields in China

• The effect of the application in 8569 wells in 12
  oilfields in China up to Dec. 2006

6.60kW
Input Power per Well
9.38kW
30.71
17.08
System Efficiency
Power-Saving Ratio
29.6
Annual power saved per Well
28,088kW.h
71
Test Effect in Daqing Oilfield( 11 wells in the
Sixth Production Plant )
Input Power Reduced by 5.6kW,from 15.71kW to
10.11kW Power-saving Ratio35.6 System
EfficiencyIncreased by 17.35

72
Effect in Daqing Oilfield
Applied wells771 Input PowerReduced by
3.11kW,from 10.14kw to 7.03kw Power-saving
Ratio30.68 System EfficiencyIncreased by
16.44 from
22.26 to 38.7
73
Test Effect in Liaohe Oilfield22 wells in
Huanxiling Company
Input Power Reduced by 3.12KW, from9.8kW to
6.62kW Power-saving Ratio 31.8 System
Efficiency Increased by 12.12
74
Effect in Liaohe Oilfield
Applied Wells3672 Input PowerReduced by 2.80kW,
from 9.3kW to 6.5 kW Power-saving Ratio
30.08 System EfficiencyIncreased by 12.45
from 13.56 to
26.01
75
Effect in Dagang
Applied Wells454 Input PowerReduced by 2.72kW,
from 22.46 to 38.77 Power-saving
Ratio26.01 System EfficiencyIncreased by
16.31 from 22.46
to 38.77
76
Effect In Changqing Oilfield
Applied Wells155 Input PowerReduced by 1.12KW
from 3.73KW to
2.61KW Power-saving Ratio30.06 System
EfficiencyIncreased by 7.8
from 14.09 to 21.89
77
Effect in Sinkiang Oilfield
Applied Wells15 Input PowerReduced by
2.1kW,from 6.44KW to 4.34KW Power-saving Ratio
32.6 System EfficiencyIncreased by 11.48,
from 17.66 to
29.14
78
Test Effect in Shengli Oilfield20 wells in
Zhuangxi Company
Input Power Reduced by 4.14kW,from 12.09KW to
7.95 KW Power-saving Ratio34.2 System
Efficiency Increased by 16.7
79
Contrast of Well TBO
?Effect in Huanxiling Company(2000-2001)
Wells for Evaluation17 Well TBO prolonged by
40.7 Operating Cost reduced by 40.7
80
Contrast of TBO
? Statistics in Jiangsu Oilfield
Wells for Evaluation42 Well TBO prolonged by
37.6 Operating Cost reduced by 37. 6
81

• Effect Analysis

28,088kW.h/year
Power Saved per Well
30
Prolonged Well TBO
Electricity Cost 2000/year Operating Cost
1430/year
Cost Saved per Well
700/year
Investment per Well
14.8
Ratio of Input to Output
29,000,000 for applied 8569 wells
Annual Profit
82

• Pumping Star in CNPC

In 2007, CNPC installed 300 sets of Pumping Star
for its 13 oilfields.
OILFIELD NUMBER OF SOFTWARE OILFIELD NUMBER OF SOFTWARE
Daqing 90 Jidong 7
Jilin 35 Dagang 15
Sinkiang 38 Huabei 15
Qinghai 7 Changqing 35
Yumen 7 Xinan 3
Tuha 7 Liaohe 35
Beijing 2 Talimu 4
83

• Pumping Star in SINOPEC

Up to 2007, SINOPEC had installed 27 sets of
Pumping Star. In 2008, SINOPEC plans to install
150 sets of Pumping Star for its 8 oilfields.
84
Contents

1. Overview
2. The theory of calculating the input power of a
   sucker-rod pumping system
3. Patented design method and its software for a
   rod pumping system with least energy consumption
4. Applying effects in oilfields Practice
5. Achievements and Market potential

85
5.Achievements
In the patent, all kinds of power consumption in
pumping process are analyzed systematically.
Theoretical and technical innovations to
petroleum engineering have been made in the
following four aspects
1).Foundation of the calculation theory formula
for pumping system input power
2).Invention of the design method for a pumping
system on the principle of consuming least energy
while producing the target output US
patent No US 6,640,896 B1 CN patent
No ZL 99 1 09780.7
86
3).Development of Pumping Star based on the
patented design method
4). Proposition and application of the devices
modification to fit the patented design method
87
In 2002,Pumping Star was affirmed by Science
Technology Office of Jiangsu Province as
high-technical production.
In 2005, this expertise won the Prize for
Technology Invention of SINOPEC
In 2006, Pumping Star was certificated one of the
National New Products by the Ministry of Science
Technology of P. R. China.
In 2006, this expertise was chosen into the 11th
Five-Year (2003-2008) Plans Promotion List of
Energy Efficiency Technology in High Energy
Consumption Industries by the National
Development Reform Commission of P. R. China.
88
In 2007, Pumping Star was granted the
Innovation Fund of Jiangsu Province.
In 2007, Pumping Star was chosen into the list of
ltRecommendation Catalog of Energy-saving
Electronic Information Technology, Products and
Application Programsgt by the Ministry of
Information Industry of the P. R. China.
89
Market Potential

• In China, sucker-rod pumping wells count
  up to about 100,000. If the patent could be
  applied to all these wells, the anticipated saved
  power would approximate 3 billion kilowatt-hours.
  Meanwhile, the well TBO (time between overhaul)
  would be prolonged and operating cost would also
  be reduced by about 1/3 accordingly.
• There are about 930,000 sucker-rod pumping
  wells all over the world. If this patent could be
  widely promoted among these wells, a large energy
  saving would be brought about.

90
Estimation for CNPC
Total Wells
99,517
Wells in Production
78,861
Reduced by 3.78kW
5.34kW
9.12kW
Input Power
36.98
Increased by 15.32
System Efficiency
21.66
Average Power- Saving Ratio
41.42
Annual Power Saved per Well
31738kW.h
Total Power Saved Annually
2,503,000,000kW.h
91
Estimation for SINOPEC(2005)
Total Wells
22,900
Wells in Production
18,021
Input Power
Reduced by 3.38kW
6.51kW
9.89kW
Increased by 2.63
System Efficiency
36.96
24.33
Power-Saving Ratio
34.2
Annual Power Saved per Well
28,392kW.h
Total Power Saved Annually
512,000,000kW.h
92
End