Minitab tool to evaluate PM (Preventive Maintenance) process

#1
Hello,

I just want to seek an advise from you guys about a study that I am working on.
I need to evaluate the effectiveness of preventive maintenance process using statistical tools in minitab.
Given data are the following:
1. Number of defectives for Assembly Line 1 per day
2. Number of defectives for Assembly Line 2 per day
3. Cumulative data counter at the time of a PM cycle
I have attached a sample data.

I am confused what statistical tool or graph to use to stratify the data (and perhaps to do a test?) and show how effective the PM cycle for Assembly Line 1 and 2.
Do you have any ideas using the given the data.

I tried P-chart but I am not sure if it is appropriate.

Thanks,
miongski
 

Attachments

Last edited:
Elsmar Forum Sponsor

Miner

Forum Moderator
Staff member
Admin
#3
I think a p-chart is an appropriate tool to use. You can split the worksheet into 2, one for each production line. Calculate your limits, excluding out-of-control data. I noticed that these out-of-control points seemed to be followed by maintenance, whereupon, the chart was back in control. Are you certain that these are PMs, or are they corrective maintenance?
 
#4
Hi Miner,

I missed to include this information, PM should be done every 4000 parts processed.
I used the P-chart as shown below, I used the "Parts Processed" data as Subgroup Size instead of "Cumulative Parts Processed Counter" (is this correct?). The out of control points seems to be from PMs that was made beyond the 4000 parts.
So you suggest to remove these 4 out of control points, then calculate control limits, below is the p-chart showing the out-of-control points.


1555955227131.png


Below is the p-chart after removing the 4 out-of-control points, now its showing new 2 out-of-control points. Will I remove this 2 points again then create another p-chart using the UCL and LCL below?

1555955764275.png
 
#5
I think a p-chart is an appropriate tool to use. You can split the worksheet into 2, one for each production line. Calculate your limits, excluding out-of-control data. I noticed that these out-of-control points seemed to be followed by maintenance, whereupon, the chart was back in control. Are you certain that these are PMs, or are they corrective maintenance?
Hi Miner,

I missed to include this information, PM should be done every 4000 parts processed.
I used the P-chart as shown below, I used the "Parts Processed" data as Subgroup Size instead of "Cumulative Parts Processed Counter" (is this correct?). The out of control points seems to be from PMs that was made beyond the 4000 parts.
So you suggest to remove these 4 out of control points, then calculate control limits, below is the p-chart showing the out-of-control points.



1555955227131-png.png



Below is the p-chart after removing the 4 out-of-control points, now its showing new 2 out-of-control points. Will I remove this 2 points again then create another p-chart using the UCL and LCL below?


1555955764275-png.png
 

Miner

Forum Moderator
Staff member
Admin
#6
You are on the right track. It is a bit of a judgement call on when to stop. I suspect that when you remove the two red points plus the 3 close to the limits, you will have a good estimate of p-bar. You can then set p-bar to that level under Options > Parameters > proportion and include all of the data points.
 
#7
You are on the right track. It is a bit of a judgement call on when to stop. I suspect that when you remove the two red points plus the 3 close to the limits, you will have a good estimate of p-bar. You can then set p-bar to that level under Options > Parameters > proportion and include all of the data points.
thanks for your help. I will try it.
 
Thread starter Similar threads Forum Replies Date
D Best Minitab Tool to determine a Statistically Significant Trend Using Minitab Software 5
C Minitab - How to enter results (tool damage situations) Using Minitab Software 10
M Minitab macro vs. Layout tool Using Minitab Software 9
Q Johnson Transformation Tool - Minitab Using Minitab Software 4
Z Minitab - Updating Graph with specific data points Using Minitab Software 2
S Need help with analysing a survey on minitab Using Minitab Software 1
M Minitab assistant: 1-Sample % Defective Test Using Minitab Software 1
0 Interesting Discussion Analysis of half normal distribution in minitab Using Minitab Software 11
G Batch printing reports in Minitab Using Minitab Software 3
B Minitab Type 1 Gage Study on True Position Question Measurement Uncertainty (MU) 1
V Minitab GRR crossed Xbar and r method macro needed Using Minitab Software 9
I Number of decimals in equation calculated by MiniTab Using Minitab Software 0
A Acceptance p-value for linearity and bias analysis in minitab results Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 0
M How to change the display of optimization plot in Minitab 18 Using Minitab Software 2
E Input to ANOVA 1-WAY - How can I perform this analysis in minitab? Using Minitab Software 2
N Tolerance Interval plots in Minitab Statistical Analysis Tools, Techniques and SPC 0
J Including Repeats in DoE using Minitab Using Minitab Software 5
A Minitab 18: How to automate GRR Summary Table save Reliability Analysis - Predictions, Testing and Standards 1
N What subcommands can be used with "Stop" in Minitab 18? Using Minitab Software 8
S Minitab - Factor Analysis: Label on second series of data for Biplot Using Minitab Software 4
J Which Anova dropdown to use for R&R in Minitab? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
J DoE - Number of runs in Plackett-Burman (Minitab) Using Minitab Software 2
D Asterix when pasting a column of values from Excel into Minitab (V17) Using Minitab Software 5
A Generating samples from a population in Minitab Using Minitab Software 0
Ron Rompen Random data generation in Minitab Statistical Analysis Tools, Techniques and SPC 2
I DOE: High variance and small effects in Minitab Using Minitab Software 1
B Informational Expanded Gage R&R Analysis using Minitab Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 18
R Rank Deficiency Error Minitab Using Minitab Software 5
H Minitab 15 - Factorial Design - 3 factors: 4x3x2 - How to? Using Minitab Software 4
A Capability Analysis for Packaging Seal Strength with spec. >0.1 Kgf using Minitab Using Minitab Software 6
Coury Ferguson MiniTab 17 Question-Standard Deviation Default Capability, Accuracy and Stability - Processes, Machines, etc. 5
N Regression Model (Minitab 18) - Which values my input parameters should have Using Minitab Software 2
L MINITAB 17 - Changing Data Using Minitab Software 3
R Conjoint Analysis - Minitab 18 Statistical Analysis Tools, Techniques and SPC 2
F How to make an ANOVA of a design with repeats (not replicates) in Minitab? Using Minitab Software 18
W Definitive screening design in Minitab 17 Manufacturing and Related Processes 1
S Minitab runs at different speeds on identical PCs Using Minitab Software 5
S Response Surface Method to create design matrix in Minitab Using Minitab Software 5
S Minitab limit definition from R & R Using Minitab Software 4
G ANOVA GR&R: Minitab vs AIAG MSA results Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
S Standard Deviation Selection on Control Charts - Minitab "pooled deviation" Statistical Analysis Tools, Techniques and SPC 3
P Minitab Data Analysis - Understanding if a Process is in Control or Not Using Minitab Software 2
P Basic Minitab Help - It's about Linear Regression Using Minitab Software 1
A Taguchi Minitab - Continuous Data - What should I choose as response variable? Using Minitab Software 3
K Taguchi Experiments for Factorial Design Analysis - Reliability of Minitab Results Using Minitab Software 1
G How to create a mixed OAs in Minitab Using Minitab Software 1
V Looking for advice on Pooled Standard Deviation between Minitab and MS Excel Statistical Analysis Tools, Techniques and SPC 1
N DOE (design of experiments) in Minitab 16 Using Minitab Software 6
R How To Calculate & Print CDF and Lower Bound CDF value for some t(time) with Minitab? Using Minitab Software 1
D minitab macro to pull access query with parameters Using Minitab Software 1

Similar threads

Top Bottom