What is Backflushing in Manufacturing?

Backflushing is the flow reversal of materials, typically liquids, to flush any contaminants that have built-up through a filtering system. For example, with water treatment plants, water I filtered through a sand filtering system removing all or most impurities from the water. At times the flow through the sand is reversed forcing any contaminants to the surface so they can be removed. While this example doesn’t relate to inventory management, it is a term that describes the method used for sending materials to production orders at the point where a specific production operation is completed.

When a production order is created, basic information is entered which typically includes the requested quantity, item number, and requested date. This information is then used to create a parts list or pick list (also known as a materials list) as well as the routing for that particular order. When it is time to start the production process, several methods are used to gather the required materials. One method is to use the materials list to pick the materials and take them to the production area. Then, you will use a software program to route all components to a specific production order. You will be able to choose the materials list as one transaction and the program will issue the quantity for each detail line to the production order. You will have the option to change the quantity of materials in the program for each detail line or issue orders to one specific detail line.

Backflushing is essentially postproduction issuing. During this process you are not actually issuing materials until production has been reported against a specific operation. The materials may be obtained through whatever methods are most efficient for the operation you are initiating. Once the operation has been completed, the operator uses a program to post production against a specific operation. That person will usually enter the production order number, quantity good, operation, scrap quantity, and information related to labor and machines. This production reporting software will then bring up the issuing program; it uses the sum of the good quantity and scrap quantity to recalculate how much of the required materials are needed to perform the job. That person will then issue all materials as one single transaction exactly how they would have in the preproduction issue. Blind backflushing is also an option that can be used. This is where the issuing program is working in the background without it ever being seen by the operator.

Some of benefits of backflushing include simplified postproduction issuing, makes it easier to take a count on the materials being used, reduces the risk of materials being placed in the on-hand inventory balance for longer production runs, makes tracking inventory much easier and hassle-free, and prevents any instances of reverse issuing of materials when using bulk materials that are in stock.