Many of us are missing the thrill of watching live sporting events during the COVID-19 pandemic. Yet, I’m sure you can remember fantastic plays or edge-of-your-seat games, and I bet the best ones did not include a missed call from a referee.
No one wants the action interrupted by someone breaking the rules, but it happens. It’s similar with error-proofing in manufacturing. The monitored action continues smoothly until a “rule,” or defined parameter, is not met. It’s then that error-proofing in manufacturing steps in, and the process is interrupted.
As opposed to referees, who can be subjective in their calls, error-proofing software is always consistent, allowing for a repeatable process of defect-free parts.
The Importance of a Repeatable Process
Increasing productivity and maintaining high quality are only possible when the work is standardized, and the process is highly repeatable. Repeatability is also key to minimizing costly defects and achieving savings that boost the bottom line.
Creating a repeatable process is one of the cornerstones of an MES (manufacturing execution system) solution, which allows you to configure the processes you want — everything from product details to operator schedules — and then use it plant-wide. This provides a “sleep well at night” confidence that the process is being executed exactly as it is defined.
Error-proofing refers to the implementation of fail-safe mechanisms (and enables “no fault forward” strategies) to prevent the production of defective parts. The core philosophy of error-proofing is that it’s unacceptable to manufacture even a few bad parts. The only way to achieve this goal is to prevent defects from happening in the first place.
Error-Proofing: the Fundamental Piece of a Repeatable Process
A task can be consistently accomplished exactly as it’s defined by monitoring input from operators and hardware. With error-proofing in the picture, whatever can be monitored is monitored.
Confirmation tells if the event has been done within specifications and tolerances, and error-proofing ensures that any mistake is handled before the product moves forward in the assembly process.
So, mistakes aren’t counted and shared at the end of a week’s work or even a shift; the second something falls out of tolerance, error-proofing comes to the forefront. The product will not release out of station unless it meets specifications, has data to prove it, and all previous steps are successfully completed.
For instance, when tightening a nut on a bolt, a transducer in a fastening tool can measure exactly what torque was applied. That torque level can be consistently verified 100 times out of 100.
Think of error-proofing as being part of an MES solution’s DNA — from simple checklists to custom test equipment, the sophisticated software doesn’t simply guarantee product integrity, it includes 100% product traceability (more on this later).
Manufacturers make investments in expensive tooling and hardware that have the capability to report what they’re doing. MES software grabs that performance data, evaluates it and, based on specifications, determines if it’s acceptable or not.
What Kind of Data Can Be Error-Proofed?
You want to enforce a repeatable process by error-proofing everything you possibly can: Every significant piece correctly installed into an assembly. Every bolt properly tightened. Every step followed.
It’s possible to apply error-proofing to many manufacturing events:
- Gauging parts
- Making part selections
- Fastening
- Leak testing
- Part marking
- Pressure testing
- Electrical testing
- and many more
Error-proofing can also be customized for various assembly events. For instance, an oil fill machine can be error-proofed to ensure an exact amount of oil is used. If it’s overfilled or underfilled, error-proofing catches the mistake and makes sure the repeatable process is followed.
Consider the old-school way of statistical process control. A sampling of products was tested, perhaps 1 out of every 10, to observe the effectiveness of the process. Today, software systems measure every part, every piece. Why test 10% of products when you can now test (and confirm) them all?
The Value of Error-Proofing
Recalls are expensive. Building a reputation takes time. Brand loyalty is a rarity. How many errors can be tolerated by customers when your competition is knocking on their door? With error-proofing on your side, you have a new favorite quality-control weapon.
Is error-proofing really “error-proofing” (completely eliminating errors)? Yes, when it comes to the configurable parameters that are determined prior to manufacturing. Error-proofing doesn’t provide a warning that a product will fail, it alerts when one does. So, in that sense, it does eliminate errors based on the specifications.
Product traceability is also part of the MES system’s product data set, so you know exactly how the product was built, piece by piece, as it was built. Tomorrow, two months, or two years from now the data set for one particular product is available to review. Entering the serial number reveals the product’s components as well as the results of any testing that occurred throughout the manufacturing process.
In a world that measures defects in parts per million, errors are less common yet, with the help of error-proofing, it’s possible to avoid them altogether.
Real-Life Examples of Error-Proofing in Action
Consider an ATV engine assembly line. How many bolts will that line tighten over a year’s time if that line manufactures 300 engines per day? About 8 million bolts, all of which need to be correctly torqued.
Now, consider additional quality control functions during the process: coolant system leak testing, electrical testing, noise and vibration testing, etc. That level of production demands an MES system’s error-proofing functionality throughout to ensure a repeatable process every time.
Here’s another example (also an engine), but this one is for a high-performance automobile. As the 1,000-horsepower engine is assembled, error-proofing is performed at every step, including testing and gauging done on each component — measuring bores, checking ring end gaps in bores, calculating piston-to-bore clearance, etc.
Not only does the MES system capture all data, which travels with the engine during assembly, the system uses the data to ensure each step happens in the correct order. The operator can’t move to the next step until the prior steps are completed, therefore eliminating any human error.
Hundreds of measurements are taken on each engine, testing thousands of parts per week and capturing precise measurements. Error-proofing confirms part integrityand ensures every manufacturing step is achieving the desired results, upholding the brand’s reputation and boosting the bottom line.
Learn more about error-proofing and how using an MES system ensures that high-quality standards are always met. Contact PINpoint Information Systems. Complete this form or call 905-639-8787.
