What is Bill of Materials (BOM)?

A bill of material (BOM) is a list of raw materials, sub-assemblies, or any labor required for manufacturing a specific item. It provides detailed information about the quantity, description, and specifications of each raw material required to manufacture the final product. The materials listed in the BOM get consumed to produce the final manufactured item.

There are typically two main types of BOMs:

1. Single-Level BOM: This type of BOM lists all the components or raw materials directly used in manufacturing a product.

2. Multi-Level BOM: In a Multi-Level BOM, some or all of the materials listed in the BOM can themselves be produced. This means that this BOM includes a sub-BOM for these materials, detailing the steps required to produce them

Creating a BOM

Creating a BOM entails entering the details of the manufacture item number, bill of material name, instructions, validity, and revision #. The details section allows you to add components, item qty, and instructions.

Entering a BOM

When entering a BOM, you'll begin by entering header-level information, such as the manufacture item number, bill of material name, instructions, validity, and revision #.

Adding Components to a BOM

Once the basics are set, you will begin to enter the raw materials to the bill of material. Click on "Add Raw Materials" to add the component, the item quantity and instructions for using the raw material.

Add Items Fields

Bill Of Material Components Fields

After completing the header fields and adding the components, click on "Save" to create a BOM.

Creating BOM Revisions

A BOM revision allows you to make continual updates to the specifics of a BOM during the entire product lifecycle. It also provides a user-friendly historical log of all revisions made. You can use the revisions to analyze and monitor cost reductions, especially when multiple BOM revisions are used in the production process.

BOM revisions can be created in two ways:

Creating BOM Revision from the Bill Of Material module

To create a BOM revision, open an already existing BOM and make the necessary changes, such as adding or removing items or adjusting quantities.

After the changes have been made, specify the Revision # and validity dates (Valid From Date and Valid To Date) in the BOM header section. Then, navigate to Options and select "Save as New Revision" to create the new revision.

Creating BOM Revision via upload

Fill in the details of the revision in the upload BOM file, making sure to enter the Revision, ValidFromDate and ValidToDate columns. Set the "Is Revision" flag to true.

Then, upload the file in the Upload Bill Of Materials module to create a new revision.

Updating BOM Items

Keeping an up-to-date and accurate Bill of Materials (BOM) is essential for ensuring that products are built efficiently and to specification. If the raw material or the raw material quantity used for producing a good has been updated, you can use the "Update BOM Items" module to change the raw material in a BOM.

There is a dropdown for “Update Type” in the “Update BOM Items” module. The Dropdown has two values: Bill of Material & Manufacture Orders.

To change the item or the item quantity of the raw materials of a BOM, select the "Bill of Material" update type. The "Manufacture Orders" update type allows you to update the item quantity on a manufacturing order.

Update Type: Bill Of Material

• If the BOM option is selected, then the data is loaded based on Items used in the Bill of Material. From here, the Qty and Item of the Raw materials in BOM can be updated.

• Select the BOM you want to update and choose the Replacement Item# and Qty. Click on Update Selected Records if you want to update selected BOM Items.

• To make changes to all the related BOM Items, update the BOM Items and click on Update All Records from the drop-down menu.

Update Type: Manufacture Orders

• If the Manufacture Order option is selected, then data is loaded based on Items used as Raw Material in the Manufacturing Order.

• This will update the Qty of the Raw Material.

• Search the Raw Material Item Number for which you want to update the quantity.

• It will fetch all the MOs in which the Raw material is used.

• Select the MO you want to update, change the Qty, and click on Update Selected Records.

• To make changes to all the related MOs, update the quantities and click on Update All Records from the drop-down menu.

**Please note that you can only void the bill of materials that have not been utilized in the manufacturing of an item.

Deleting BOM Items

In XoroERP, deleting a BOM is subject to specific rules to ensure data integrity and avoid disrupting manufacturing processes:

1. General Rule for BOM Deletion: By default, a BOM can only be deleted if there are no Manufacturing Orders (MOs) created for that BOM. If an attempt is made to delete a BOM with active or historical MOs, an error message will be displayed, preventing the deletion.

2. If the "Is Manufacturable?" Flag Is Set to False: If the "Is Manufacturable?" flag for a BOM item is updated and set to false, the BOM can only be deleted under the following conditions:

   • There are no MOs created for the item.

   • Any existing MOs for the item have been completed (status: Produced) or reversed (status: Disassembled).

   If any MOs are in a status other than Produced or Disassembled, the system will display a specific error message. This safeguard prevents accidental deletion of BOMs linked to ongoing or incomplete manufacturing activities.