1. Presented by Katie Krupla
August 4, 2015
1

2.  My project was to analyze and present the Farr plunger
performance.
 The purpose was to analyze data from the Coalinga field
to compare the performance of the Farr plunger to other
plungers used in the same wells.
 Based on field observations, the Farr was suspected to
provide longer runtimes on average and require fewer well
pulls than other plungers used in the same wells.
 We needed to determine if the observations could be
supported by quantitative analysis, and if so, see how
much longer Farr runtimes were on average.
2

3.  Over 100 years old
 Layered
unconsolidated
sandstone reservoir
 Heavy oil
 Over 700 producing
wells
 Many wells produce
sand
3
Photo Credit: "CoalingaWell" by Antandrus via Wikipedia

4. Photo Credit: www.muthpump.com
4
Main Design Modifications
 Top plunger connector
 Farr Leading Edge

5. Connector
5
Photo Credits: www.muthpump.com and Muth Pump LLC
Conventional Farr
US Patent # 6,543,543 B2 Connector
Leading
Edge
Scarring

6. Excluded or corrected inaccurate runs
Filled in missing plunger types using pump run tickets
Removed duplicate lines of data using additional well data sources
Included 2 pump pulls prior to Farr and any pulls after Farr**
Excluded wells that had never had a Farr plunger in them*
Only looked at Coalinga Data
* If the well had only had Farr plungers in it, it was included in the study.
**Study goes back to 2010 when the first Farr plunger was installed in
Coalinga Field. 6

7. 0
20
40
60
80
100
120
140
160
-609.56 -302.79 3.99 310.76 617.53 924.30 1231.07 More
Frequency
Non-Farr Bin
NON FARR RUNTIME Histogram
Right Skewness
Leptokurtic
Distribution
0
20
40
60
80
100
120
-555.06 -254.30 46.46 347.22 647.98 948.74 1249.50 More
Frequency
Farr Bin
FARR RUNTIME Histogram
7
Right Skewness
Leptokurtic
Distribution

8. 8
FARR RUN_DAYS NON FARR RUN_DAYS
Mean 347.22 310.76
Standard Error 21.94 21.43
Median 238.99 205.00
Mode 163 138
Standard Deviation 300.76 306.77
Sample Variance 90456.22 94108.70
Kurtosis* 2.33 1.49
Skewness 1.45 1.47
Range 1614.21 1365.29
Minimum 1 2
Maximum 1616 1367
Sum 65277 63705
Count 188 205
Mean Confidence Level(95.0%) 43.27 42.24
*Kurtosis was calculated in Excel. The normal distribution has a
kurtosis value of zero in Excel.

9. Plunger Count Failed % Still Running
Farr 188 94 50.00%
Non Farr 205 182 11.22%
Significance:
 50% of all Farr plungers are still running.
 Only 11.22% of all Non-Farr plungers are still running.
 The large percent of Farr plungers still running requires that
we rely on the projected median runtime in the next slide to
explain the data.
9

10. Non-Farr
Farr
Combined
Non-Farr
Farr
Combined
--- Non-Farr
--- Farr
 TheprojectedmedianruntimeforFarris
470days.Theprojectedmedianruntimefor
Non-Farris217days.
 Thus,theFarrhasa216%longerprojected
medianruntimethantheNon-Farr.
 Thisisa116% improvement.
Survival Plot:
Farr vs. Non-Farr
10

11.  Two manufacturers were
used for the study.
 They were given
different geographical
areas to test.
Results:
 No statistical difference.
 Assembly bias is not an
issue.
 Farr’s performance was
identical in both
geographical areas.
Plunger Count Failed Plungers % Running
HF 78 36 54%
John Crane 110 58 47%
11

12. 12

13.  The survival plot shows that
there is no statistical
difference between the two
pump bore sizes based on
the overlapping curves and
additional statistical
analysis.
 We conclude that the Farr
runtime data is not biased
based on pump bore size.
13

14. Scenario:
If 100 Farr plungers are installed in one year,
then there would be a total yearly savings of
more than $874,368.
Savings/well/year
$8,744
Cost/pull Projected median runtime Cost/well/day Cost/well/year
Farr $10,400 470 days $22 $8,077
Non-Farr $10,000 217 days $46 $16,820
14

15.  Significance of our Findings:
◦ Proves that Farr plunger runs longer than Non-Farr
plungers.
◦ Farr Plunger provides 216% longer runtimes.
 Greatest Application:
◦ The Farr plunger is a solution to sand production
problems that will cut costs.
 Further Research:
◦ As the percent of Farr plungers still running
decreases, it will be interesting to see how much
greater the percent improvement gets.
15

16. Muth Pump LLC
Rod Kane - Coach
Marc Obenshain
Matt Grimm – Statistical Advice
Ben Krupla
16

17. Non-Farr
Farr
Combined
Non-Farr
Farr
Combined
--- Non-Farr
--- FarrQuestions
17