Whenever there are two or more working copies of the same file or document, there is an increased potential for change edits where one or more of the documents no longer reflect the latest version of the part or assembly of record. If there is no centralized Documentation Control operation, then it is difficult to tell who has the “correct” version and who is working from a copy that is out-of-date.
Imagine that Engineering has changed a drawing, but Purchasing has the unmodified version of the same drawing filed by part number in its files and has attached that version to a purchase order that had been sent to a fabrication house to make 500 parts at a considerable cost. The parts are ordered, received, and sent to the factory floor. The assembly line stops, because a fastener location has been moved slightly to make it possible for the part to be used in other assemblies, but not the assemblies scheduled for completion today.
Had the latest document, edited by Engineering, been given to Purchasing, the part ordered would have been fabricated with both old and new assemblies in mind. What happened? Here are three possible answers:
- Design intent . Engineering recognized the need to reduce cost in its design by modifying the old design to work with all assemblies. This would reduce inventory part count and lower costs by consolidating purchasing volume requirements across many assemblies and simplifying the assembly effort. This is the practice of “Design Intent” in action.
- Not enough information . Purchasing was maintaining its own files and did not know of any changes to the part or drawing at the design level. Purchasing believed it had the latest technical drawing and could order as the MRP Forecast had required.
- Lack of documentation . Engineering may have informed Purchasing verbally of the pending changes, but that isn't the real problem. The company had no real documentation control process or procedure. In fact, Purchasing may have been told that a change was coming and to hold off purchasing any new parts until the drawings were released, but the person who was told was not the person who purchased the parts.
Word of mouth is never sufficient for documentation or part change issues. In the next part of this series, I will review certain critical steps that could have been taken to avoid this problem. The terminologies to keep in mind here include the following: Revision Control, Documentation Control, ECR/ECO/ECN Procedures, and the CRB or Change Review Board. Don't worry. I'll explain further, but let me know what could have been done differently in the above scenario.