In a contract manufacturing environment, there are three main approaches to managing internal assembly revisions.  Complete Internal Control, Complete Customer Control, and Combination.  Each has important considerations and will be explained below.  The approach selected will determine procedures for handling changes and tools needed to manage those changes.

 

 

With this approach, the internal assembly revision is set and updated independent of the customer's assembly revision.  For example, all new assemblies will receive an internal revision of 1 (indicating it is the first version of the build).  With each change to the assembly (regardless of significance or how the customer handles it) the internal revision will change.  This makes it very easy to identify the most updated version of the assembly as well as how many changes the assembly has had since the start of production.

 

If the customer always and exclusively produces the latest revision of a product, then this method simply requires users to verify that they are ordering and producing the latest revision.  However, if the customer orders older revisions, this method may make it more difficult to correctly select the appropriate internal revisions and must have appropriate safe guards in place to reduce the possibility of human error.

 

Additionally, it can make communication with the customer more of a challenge as employees may use the internal revision, while the customer uses their own revision.  This can be overcome with tools to match internal and customer revisions.

 

Because each change results in a new revision, this approach requires only a method for matching the customer's revision with the internal revision.

Complete Customer Control -

 

With this approach, the internal assembly revision is set to match the customer's assembly revision.  Regardless of how many changes, or the types of changes the customer or company make, the revision always matches that of the customer.

 

While this method removes the responsibility of managing the revision from the contract manufacturer, it does increase the potential for human error.  This is especially true if the customer does not always make a revision change each time they update their product.  As with NE Company, it creates the possibility of producing the correct revision, but not the correct configuration.

 

For this approach to work, users need tools to effectively document when and what changes were made, and processes to verify that all changes have been appropriately and completely applied to the assembly documentation.

 

Combination -

 

Regardless of the approach selected, it should be uniformly applied to all assemblies and customers to simplify processing and reduce the possibility of mistakes.