Fault Diagnosis Method and Application of ESP Well Based on SPC Rules and Real-Time Data Fusion
Table 2
Extended SPC rules.
Serial number
SPC guidelines
Trend characteristics
Specific rule
1
Guideline 1
Sudden increase
A point falls on the center line CL and outside of zone A
2
Guideline 2
Sudden drop
A point falls below the center line CL and outside of zone A
3
Guideline 3
Rise
9 consecutive points fall outside of zone B above the center line CL
4
Guideline 4
Decline
9 consecutive points fall outside of zone B below the center line CL
5
Guideline 5
Rise
6 consecutive points increase, and the last point is outside of zone A
6
Guideline 6
Decline
6 consecutive points decrease, and the last point is outside zone A
7
Guideline 7
Fluctuation
Adjacent points in consecutive 14 points alternate up and down, and the difference between the maximum value and the minimum value is greater than 3 times the standard deviation
8
Guideline 8
Fluctuation
2 out of 3 consecutive points fall outside of zone B above the center line CL
9
Guideline 9
Fluctuation
2 out of 3 consecutive points fall outside of zone B below the center line CL
10
Guideline10
Rise
4 out of 5 consecutive points fall outside the C area above the center line CL
11
Guideline11
Decline
4 out of 5 consecutive points fall outside the C area below the center line CL
12
Guideline12
Fluctuation
15 consecutive points fall within the C area on both sides of the center line CL
13
Guideline13
Fluctuation
8 consecutive points fall on both sides of the center line CL and are not in the C zone
