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Documentation Control

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Control operation, then it is difficult to tell who has the “correct” version and who is working from a copy that is out-of-date.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 a drawing that has been changed by Engineering but Purchasing had the unmodified version of the same drawing filed by part number in their files and has attached the drawing 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?

  1. Engineering recognized the need to reduce cost in their design by modifying the old design to work with all assemblies and thereby reduce inventory part count, obtain better costs by consolidating purchasing volume requirements across many assemblies, and by simplifying the assembly effort. This is the practice of “Design Intent” in action.
  2. Purchasing was maintaining their own files and did not know of any changes to the part or drawing at the design level. Purchasing believed they had the latest technical drawing and could order as the MRP Forecast had required.
  3. 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 that was told, was not the person that purchased the parts. Word of Mouth is never sufficient for documentation or part change issues. Enter Revision Control, Documentation Control, ECR/ECO/ECN Procedures, and the CRB, Change Review Board.

Now let’s add Documentation Control procedures to this same situation.

  1. Engineering decides to modify the part to work across many assemblies. An Engineering Change Request, ECR is initiated by the individual who is requesting the change. An ECN may be used for this purpose with the understanding that at this point the Change Order is a request only and not being implemented until all departments have a chance for input. At this time, the proposed change will be supported in the form of an attached, pre-changed drawing with red-lines showing the proposed changes. The pre-change drawing is “checked out” by the Engineer from Documentation Control’s library. *NOTE: Purchasing does not have a private file for documents that are also created or used beyond their own department. This drawing is protected and controlled in one place only. Documentation Control is the official library for all company-wide documents. Purchasing has the procedure in place that mandates every time a fabricated part is to be ordered, they must retrieve the drawing from Documentation Control. When Purchasing requests the drawing, a certified, dated copy is given to them to pass on to the supplier of the part. The supplier is also instructed to not receive any purchase orders without the drawing being furnished by Purchasing at the time of the order. When a Change Order is being initiated,  Documentation Control records the date, the name of the Engineer taking the drawing for modification, and indicates in their own files that the drawing is in a “pending status” and no longer available to be used by Purchasing or any other department until the Engineer returns the original drawing or updates the document revision via an ECO, Engineering Change Order.
  2. The ECR, including all attachments is routed to all individuals and departments that will be impacted by the change. A 2nd party may be assigned to this shepherding process, or a computer may have the function as part of the feature set of the software package being used, but the routing must include the signatures of the individuals who have both the authority and the knowledge to determine the nature of the change and its subsequent consequences as it effects their areas of responsibility.
  3. 3. Once the go-ahead signatures have been obtained, the engineering change efforts may proceed.  The Cognizant Engineer will make the desired changes, update the revision section of the ECO/ECN and route the change to the necessary authorities for final approval. Some companies will begin this process with an ECR, or Engineering Change Request. This can be submitted by anyone requesting Engineering support on a design or procedure change. If Engineering accepts the request, then the Cognizant Engineer will initiate an ECO, or Engineering Change Order, following steps 1 and 2. When the work is complete and the drawings and Revisions are brought up to date, the Engineer issues an ECN, or Engineering Change Notice which is circulated to all relevant departments. See ECN Change Order Procedures under Procedures and Guidelines on these web pages.
  4. The Change Review Board is notified and sends out a meeting notification requesting the attendance of representatives from each department that will be implementing the ECN. Each member signs off on the ECN and the documentation for the entire Engineering Change, including all signatures, is checked back into Documentation Control. Old files are archived for historical and support service purposes.
  5. Purchasing is represented on the Change Review Board and so the company avoids fabricating 500 unusable parts that will end up as scrap inventory resulting as a loss from the company’s bottom line.

Documentation Control in various companies, assumes different responsibilities including, but not limited to:

Revision Control of Technical Drawings and PCB Netlist, Gerbers, and Special fab Instructions

Firmware Programs and Source Code

Mechanical Drawings

Company Procedures

ISO Documentation

Component Master Specification Files

Silkscreen Artwork

Company Quality Manual

Software Masters

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