Traceability in manufacturing means keeping track of your parts as they move through the production line. You can keep track of who handled each part, how long it spent at each step, and which reagents were used in making each part. If there’s a “bad” batch of one of your reagents, you can look through your system to find all of the parts made with that batch, so you can throw them out or rework them.
Let’s look at an example. Princess Capybara has a company making monster masks that people can use to scare their enemies.
But one day she finds that the yellow paint on one of the masks isn’t drying the way it normally does. In fact, it’s letting off noxious fumes! Something must be wrong with the paint.
Luckily, Princess Capybara has a good traceability system in place, She checks the number of the paint batch that for the mask that had the problem.
She searches her database to find all of the other masks that used the same batch of yellow paint. Then they can be quarantined in a fume hood rather than allowed to stink up the entire factory. She also finds the bottles of paint from that batch number and removes them from the production floor.
Traceability in Manufacturing: Your Secret Weapon in Troubleshooting Problems
Traceability will also make it much easier for you to find the cause of manufacturing problems. (So you can prevent the same problem from happening again!)
Princess Capybara goes across the street to the building where her workers mix the batches of paint. She looks through the records for the “bad” batch and checks the batch numbers of the ingredients, the employee badge number, and whether anything unusual happened in the process.
She immediately checks the bottles of all the component chemicals that were used in the “bad” paint batch for anything unusual: are any of the chemicals expired? Are any new bottles that might have arrived “bad” from the supplier?
Then she checks the employee badge number. If you’ve read the post on “The Fundamental Attributional Error”, you know it’s a common mistake to assume that any manufacturing problems are ALWAYS due to the person involved and not the environment or the reagents. So don’t do that! But, it is definitely a possibility that the person has something to do with the problem. (Particularly if it’s someone new.)
In this case, it was the experienced and well-trained Rhonda. Of course, anyone could make a mistake, but it’s less likely to be due to a training issue when it’s an experienced employee versus a brand new one.
In combing through the rest of the records, Princess Capybara notices from the timesheet that a longer time than normal passed between steps 4 and 5 of the process. What could be the cause of that?
Next step: Asking Questions
Princess Capybara calls Rhonda into her office for a quick meeting. Rhonda enters the office without feeling that she’s going to be yelled at, or that she needs to lie about what might have happened to the paint batch. Princess Capybara is a reasonable and logical boss who is not prone to ranting and blaming,
Princess Capybara asks Rhonda to think back and remember whether anything unusual happened that Thursday 3 weeks ago when the batch was made. Rhonda thinks back and says,
Princess Capybara checks the work instructions to see if there is anything in there about how long the paint can sit between steps 4 and 5. And she finds that… there’s not! Interesting. It’s something that never came up before.
What does Princess Capybara do next? She instructs Rhonda to do a series of experiments. This is to see what happens to the paint as it sits for different lengths of time between steps 4 and 5. The experiments find that after 35-40 minutes have passed between steps 4 and 5, the paint batches have the fumes and non-drying behavior. So, Princess Capybara modifies the work instructions. They include a note that no more than 30 minutes can pass between steps 4 and 5 of the protocol. (This way there is a bit of a safety factor built-in.)
Rhonda and the rest of the paint production staff implement the new protocol, and soon everyone is back to making scary masks!