challenging the paradigms for quality assurance
TRANSCRIPT
Challenging the Paradigms for Quality Assurance
OES Technologieswww.OEStechnologies.com
Bad processes can make good parts
It’s true, good parts can be made from bad processes, but how do you know when this does or doesn’t happen?
… should you be satisfied with this?
Tier One: a very demanding business
• Pennies per part price
• Parts per second speed
• Zero defect quality tolerance
Even one faulty product can result in expensive consequences such as product recall, diminished reputation, or worst of all, lost future contracts.
Quality testing
• Dimensional inspection
• Visual inspection
• Sample inspection
…all have their shortcomings.
Current practice:Companies have been taught to rely solely on inspection methods and devices to detect any bad products before they are shipped. The underlying assumption is that a bad part can be produced at any time and that catching these parts before they go out to customers is priority.
Inspecting the part
Visually the pipes look identical.
…Wouldn’t you like to know that the second one was produced with a 56% increase in pull force during the mandrel forming process?
Quality Testing ‐ Shortcomings
1. Limited to what can be visually seen and measured
2. Does not test hardness or thickness
3. Sample batch testing allows bad parts to slip by unnoticed (meaning faulty parts get to your customer)
4. Costs time and money to undergo procedure
5. Does not test for variation in strain, stress, displacement, etc. experienced by the part during forming
6. Allows bad processes to continue, risking part quality and catastrophic failure
Adds NO value to your part or process!
Time for a change
Why then are we continuing to inspect finished parts, risking downtime, machine failure, and shipping defective products?
There is finally a better way!
Progressive companies are leading the shift by putting more emphasis on refining and improving the manufacturing process itself.
The NEW method: Process Variation Monitoring
Focus on the PROCESS, not the finished Part.
If a process is known to be capable of producing only good parts, and the process is consistent and repeatable, then the output of good parts will be consistent also.
It’s simply about determining the quality and stability of the process.
Establish a good process.
Monitor that process.
A Good Process
A good process is a process that is incapable of producing a bad part
… unless something in that process changes.
A good process is an engineered process.
A good process is an OES monitored process.
Monitor the Process
Monitoring the process for deviation, rather than checking the parts for flaws, is an entirely new way of looking at quality assurance.
Catch problems at the source and either alert the operator or stop the production run.
Forming Example
The fail signature shows a process outside of the calculated learn curve. The result in this case was a collapsed end form on a brake tube.
Mandrel bending example
PVM technology detected a 185% increase in pull force during theproduction of the sixth tube. This early warning alerted the operator of an incorrect alignment, which had caused a wrinkled tube to be produced.
Tapping application:
Monitoring Spindle Motor Current to detect worn or broken taps.
Signature Analysis Techniques:
• Peak
• Area
• Envelope
• Force (Strain) vs. Distance (Position)
• Force (Strain) vs. Time
Tooling example
In-process monitoring of every tool cycle is critical for the detection of process variation that may produce defective products or cause catastrophic damage to the machine.
Other applications?
“Any time force is used to form, shape or fasten a product, the strain, load, or displacement experienced by the machine can be a useful indication of the product’s quality, provided you have a good process.”
Benefits of Process Monitoring
• In‐process monitoring on 100% of parts
• Capture defects at the source prior to parts moving to next stages
• Manage maintenance to reduce costs and increase operational efficiency
• Catch hidden defects undetectable by visual or dimensional inspection
• Puts the focus on the process – sustainable gains in efficiency, scrap reduction, and quality
Adds value to the process, without adding cost to the part!
The OES Advantage
Inspection method… Defects are found after they happen.(measures the part)
SPC method… Defects are found as they happen.(measures the part)
The OES PVM method… Defects are found before they happen.(measures the process)
OES ForceWorx
Process Signal Conditioners ‐ Provides force feedback for manufacturing, assembly, on‐line processing or product testing.
PSC 100 PSC 200 PSC 300 PSC 500SENSOR OPTIONS Force, Strain Force, Strain Force, Strain Force, Strain,
0‐10 VDC
ANALYSIS N/A Threshold limits Threshold limits Threshold limits
USER INTERFACE N/A Trim pot set points LCD/user buttons LCD/keypad
ANALOG OUTPUTS Continuous (0‐10 VDC), Peak hold
Continuous (0‐10 VDC), Peak hold
Continuous (0‐10 VDC), Peak hold
Continuous (0‐10 VDC), Peak hold
DIGITAL OUTPUTSN/A
Low thresholdHigh threshold
Low thresholdHigh threshold
Low thresholdHigh threshold
COMMUNICATIONS N/A N/A N/A Optional
OES ForceWorx
Process Variation Monitors ‐ Provides dynamic in‐process monitoring of 100% of parts, improving efficiency with lubrication issues, tool wear, equipment adjustment, set up verification, etc.
PVM 3000 PVM 3010 PVM 5000SENSOR OPTIONS Force, Strain, Pressure, Motor
load, DisplacementForce, Strain, Pressure, Motor
load, DisplacementForce, Strain, Pressure, Motor
load, Displacement
ANALYSIS Input vs. Time Input vs. Time Input vs. Time,Position / Distance
USER INTERFACE Via PC Via PLC LCD/keypad
ANALOG OUTPUTS N/A N/A N/A
DIGITAL OUTPUTSDIGITAL INPUTS
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COMMUNICATIONS Serial, Ethernet, USB Various PLC protocols Serial, Ethernet, USB
OES Inc.4056 Blakie Road
London, Ontario N6L 1P7Canada
Tel: 519-652-5833Fax: 519-652-3795