Machine Malfunction & Operator Errors

Made a list to capture any parts we reject. One section i put "Machine Malfunction/Operator error".

Upon presenting my list to supervisors they asked me to put into more detail for both of them.

Any idea on what i can detail them each into? I need examples of machine malfunctions and operator errors

For example Operator Error: Operator did not do periodic visual inspection.



Can anyone throw any ideas at me?

I would separate those items into separate buckets. Man or Machine or Materials or Method. That will assist in correcting.

For Operator error you could categorize into things like, Miss-load, Incorrect offset, Dropped part. These are examples that could come up in a machine shop, you would need to specialize into your business.

Let me take a different approach: Why are you doing this? Certainly such broad categories don’t add any actionable information. Being very specific about what happened might help lead to corrective action in a very few cases, but in my experience in many industries accurately assigning cause to a defect at the time of the defect is incredibly hard if not impossible without on the spot investigation. Look at your categories and honestly ask what action the category can initiate. Operator error - what will the engineer or supervisor do with that?

What I have found to be more helpful is to accurately list the nonconformance (defect) itself. What exactly is wrong with the part, not why or how it got to be wrong. IF the cause is obvious (like the machine blew up or caught fire) then list the possible cause in addition to the nonconformance. I know that many engineers wish the people on the floor could just describe what the cause is but it’s more often than not a pipe dream and frankly (and bluntly) just an enabler for engineering not doing anything.

There is a Toyota saying that is actually helpful. Go to the actual spot and see the actual Situation. Then fix it.
I cannot count all of the times I have had engineers try to do this. They made lovely excel charts (mostly pie charts and bar charts with multiple colors) and reported out the results of the data monthly. When asked what actions they were taking they always said - we need more data. We need the operator to take time to record more information in our spreadsheets. When I - or some other enlightened manager - grabbed them by th proverbial scruff of the neck and dragged them down to teh floor to watch and investigate and learn and then take actions the defect rates plummeted.

Bev D said:

...When I - or some other enlightened manager - grabbed them by the proverbial scruff of the neck and dragged them down to teh floor to watch and investigate and learn and then take actions the defect rates plummeted.

Click to expand...

Just to echo sentiments here, we used to call engineering "carpet walkers" because of their disdain of coming down the floor. But honestly 9 times out of 10, the corrective actions that came from it were meaningful. I feel like it's always been a part of my job to lead the engineers off the carpet and on to the floor haha

When I was an internal product manager I sat in on production meetings with production managers and engineers. I recall one engineer reviewing a repeated problem on the floor with a newly released part stating "just let me know when it happens again and I will look into it." The production manager and I met eyes and smiled. I knew what was going on and it was kicking the can down the road.

After the meeting, I told the Production Manager to give him a chance to solve it. If it was given lip service again to stop production and call me and the engineer. After that happened everyone knew about the problem and resources were applied to fix it.

Hybrid said:

Made a list to capture any parts we reject. One section i put "Machine Malfunction/Operator error".

Upon presenting my list to supervisors they asked me to put into more detail for both of them.

Any idea on what i can detail them each into? I need examples of machine malfunctions and operator errors

For example Operator Error: Operator did not do periodic visual inspection.



Can anyone throw any ideas at me?

Click to expand...

Here is a list I recently developed to improve the work instruction for a non-conforming parts tag as examples. "Bad part" and "out of spec" are not accepted. They get further explanation such as oversized, undersized, or possibly a value outside the tolerance.

Broke Tool (list tool)
Chamfer
Coplanarity
Counterbore
Countersink
Cracked
Cylindricity
Diameter (External/Internal)
Engineering Scrap
Flatness
Formed Wrong/Split
Form Die Marks
Groove
Keyway
Knurl
Length
Material Lamination
Material Mixed
Material Rusted
Missing Feature
Non-clean up
Parallelism
Perpendicularity/Squareness
Porosity
Position/Alignment
Radius
Runout
Surface Defect
Surface Finish
Threads
Trim Wrong
Weld Penetration
Weld Porosity
Weld Splatter
Weld Throat (Oversized/Undersized)
Weld Undercut

To address Hybrid's specific question - what are some specific causes or attributes that would result in "Machine Malfunction/Operator error"?

For example, I work in med device where we have a lot of cosmetic inspections. We differentiate tool marks or "chatter" from our mills from other kinds of damage to the edge of the parts. Though both of them are rejected, it's important to differentiate between the damage that was specifically caused by incorrect setup by the Milling technician (so the tech can be made aware of what to look out for) from damage that happened to the product from normal handling damage.

Hybrid said:

Made a list to capture any parts we reject. One section i put "Machine Malfunction/Operator error".

Upon presenting my list to supervisors they asked me to put into more detail for both of them.

Any idea on what i can detail them each into? I need examples of machine malfunctions and operator errors

For example Operator Error: Operator did not do periodic visual inspection.



Can anyone throw any ideas at me?

Click to expand...

Ok...If this is what you need to do - then you should not be asking us.

I say that because you have all the info you need (or at least should). Just go spend some time reading. Pull the data of all Machine errors and Operator errors into Excel; add a column and spend an hour or 2 bucketing the issues into a theme and poof, you got it.

EXAMPLE:

DATA (One line/event) = Tool Alarm on ch4 causing Pressure Stability Timeout; identified that CM1 failed early

• CM1 is a part; so my theme for this would be Part Failure

Pick 5-7 themes max, otherwise you can get too convoluted.

At a Navy torpedo facility where I worked many years ago - a Pareto chart came out that said that the sailors doing the maintenance were the number one cause of torpedo failures found during test firings. Caused quite a stink shall we say. Careful review of the data showed that all "sailor errors" were lumped into one bin, but equipment failures were individual to the component. So we had six sailor failures, one engine failure, one CPU failure, one . . . failure - the list was a long one. Plus many of the sailor failures were related to poor procedures supplied to the facility.

Not a bad idea to have more detail for ANY failure. The responses above should help you. Blaming the operator(s) usually is a red herring - there is something behind those failures. Consider Dr. Deming's Red Beads.