Close up of different sized ball bearings that may be included on a maintenance bill of materials.

Even though a bill of materials (BOM) makes maintenance operations more efficient and effective, many maintenance teams go without one. Often times, the absence of a BOM comes down to a lack of time, money, patience, expertise, or personnel available to build it.

To compensate, technicians, planners, and other stakeholders must find workaround solutions to complete routine tasks. This leaves organizations with a big decision to make: Should the organization invest the time needed to build a bill of materials for each of their assets or continue to deal with the consequences of poor spare part and asset management?

When you consider the impact of a bill of materials on asset reliability, the advantages are clear. Quicker maintenance and repair times, fewer errors, and simplified parts reordering reduce production downtime and other maintenance costs. Therefore, we strongly recommend that organizations that have no or incomplete BOMs create and/or update them.

This article is intended to help organizations create a bill of materials for maintenance purposes. Organizations engaged in enterprise asset management may require a more comprehensive bill of materials that meets the needs of stakeholders outside of the maintenance department. For details, read our article about how to create an equipment bill of materials (EBOM).

What is a Maintenance Bill of Materials?

Within your organization, there may be a number of bills of materials (BOMs) that serve different purposes and stakeholders, such as engineering, asset management, manufacturing, and materials management. Each of these contains varying levels of details, depending on who will use the information and how it will be used.

Typically, a maintenance bill of materials lists the replacement parts and/or materials that comprise an asset, such as a piece of equipment. These items must be repaired or replaced to keep the asset in working order. In this article, we will refer to this type of bill of materials as a bill of materials or maintenance bill of materials interchangeably.

How to Create a Maintenance Bill of Materials

Compared to other bills of materials, creating a maintenance BOM is quite easy due to its simplicity. For example, an engineering bill of materials may be a comprehensive list of any and all parts and materials that make up an asset, along with other information relevant to other stakeholders. Sifting through this level of detail would surely bog down the maintenance team’s productivity.

In contrast, maintenance BOMs are less formal. Maintenance BOMs can be created according to the following procedure.

1. Consider What Tool Will be Used to Create the BOM

Before you create your maintenance BOM, consider the best way to document the information. Using paper and pencil is not an efficient solution, as handwritten information is not easily edited and will likely need to be entered into an electronic system anyway. Like any other physical documentation, hard copies are prone to get lost.

Spreadsheet programs such as Microsoft Excel are popular and great for simple data collection and organization. However, spreadsheet software has limitations in terms of automation and ease of use. Though the tool is digital, many updates must be made manually, and it takes someone computer-savvy to set up special formatting, equations, and styling. Additionally, information stored in spreadsheets quickly becomes outdated if not consistently updated.

We recommend that you build your bill of materials in a computerized maintenance management system (CMMS). Many CMMS solutions automatically build a BOM when parts are issued against work orders. Automatically generated BOMs provide a base set of information about each part, taking away some of the guesswork and decision–making about what data to include.

As you will see throughout the rest of this process, although not required, a CMMS will provide many advantages as you create your BOM. Whichever program you decide to use, it must be used consistently to reap the full benefits.

2. Decide What Items to Include on the BOM

The needs of the maintenance process determine what items to include on the maintenance BOM. As mentioned earlier, maintenance BOMs often list only a subset of an asset’s parts. This should include all the critical components, asset-specific materials, and components that will reasonably be repaired and/or replaced.

Consumables, such as towels, gloves, and safety equipment, are usually omitted from the BOM, as they are not a part of the asset itself. Even though these items are used to complete maintenance tasks, this information is usually communicated on a work order instead.

Ultimately, a maintenance engineer, maintenance manager, or other relevant employee should determine what types of items are valuable to include on the maintenance BOM.

3. Decide What Data to Include on the BOM

There is a delicate balance between providing enough information to be useful, and providing so much detail that end users cannot find what they need. At a minimum, the maintenance BOM should identify the part or component being used. This usually includes the part’s number and name. Part quantities and usage data are also common data points.

What data is ultimately incorporated will be up to your organization to decide. Based on the system being used to create the BOM, more or less detail may be included.

Manual or spreadsheet-based systems allow you to track an unlimited amount of information. However, too much detail is often included, making BOM creation and updates a burden. For maintenance BOMs, it is often the case that less is more.

CMMS software offer a base set of data fields, which can often be expanded or reduced through configuration or customization. For the most part, the default fields provide enough information for maintenance purposes.

4. Collect Asset Data

Unfortunately, many organizations struggle with their data tracking practices. Valuable maintenance data is often scattered across several locations, and in various electronic and hard copy formats. Luckily, data about what parts are used on an asset can be obtained from multiple sources including:

  • Drawings, schematics, and catalogs
  • Equipment suppliers and other vendors
  • Similar assets and equipment
  • Engineering change notices and redesign documentation
  • Current or planned preventive maintenance (PM) work orders
  • Previous unplanned work orders
  • Work order history records
  • Personal inventory lists and cheat sheets
  • Equipment nameplates
  • Physical asset inspections
  • Veteran employees and other experienced “go to” workers

Collecting data will be easiest for new assets. Original equipment manufacturers (OEMs) provide comprehensive documentation along with new assets, including an extensive list of spare parts. Data for existing assets can be obtained from one or more of the sources listed above.

During data collection, it is most common to store data in a spreadsheet. Information can easily be transferred into a CMMS when needed. As an added bonus, digital maintenance documentation can be uploaded to the CMMS for easy reference.

5. Review Asset Data

As you collect data, you’re bound to encounter information that is conflicting, out of date, or obsolete. If you encounter discrepancies, cross-check between multiple sources to ensure the most up-to-date information is used. It is imperative that the data you have is accurate. Inaccuracies or working from old information leads to a number of issues. For example, if the wrong part is listed, the correct part will need to be located or ordered. This may result in unnecessary downtime caused by tracking down parts or avoidable emergency shipping charges if a new part must be ordered.

Learn more about MRO inventory management.

6. Enter Data in the CMMS

After gathering all required information, enter part data into the system where the maintenance BOM will exist. If using a spreadsheet, this step will already be complete. If using a CMMS to build the BOM, data entry should be performed by someone proficient with the system that can enter data into required fields.

Once part data is loaded into the system, it must be linked to its specific asset. This is difficult in a spreadsheet; use a CMMS instead. As previously mentioned, many CMMS solutions automatically build BOMs when parts are issued against assets on a work order. Otherwise, you may build BOMs manually.

One advantage of using a CMMS to create your maintenance bill of materials is the ability to view BOMs from a part- or asset-centric view. From an asset record, you can see all the parts included on the BOM. In most cases, the CMMS part record has a “where used” tool, listing all the assets on which that part has been used or assigned.

Read Also: CMMS Data Transfer Best Practices

Maintaining the Bill of Materials

As much as one would prefer them to be, maintenance bills of materials are not “set and forget.” BOM data changes over time, and if changes are not made to an asset’s bill of materials, the wrong parts will be listed. Some reasons BOMs require modification are as follows:

  • A supplier provides a new and improved version of a part
  • Older parts become obsolete and an alternative is required
  • A vendor changes its part catalog name and/or number
  • Changes or modifications to an asset’s design require new and different components
  • Parts become standardized across similar assets or across plants
  • Similar parts are ordered from a new supplier

Managing and tracking changes is a challenge when done in a spreadsheet or other manual system. A CMMS makes maintaining the bill of materials easy. Changes made in a CMMS are only required once and reflected throughout the program. Your team benefits by always using the most-up-to-date information.

Manage Parts with FTMaintenance

FTMaintenance is a CMMS solution that allows you to track maintenance assets and MRO inventory. It offers automated features that allow you to quickly and easily build and manage bills of materials. Along with other powerful CMMS features, FTMaintenance is an all-in-one platform for documenting, managing, and tracking maintenance activities. Schedule a demo of FTMaintenance today.

See FTMaintenance In Action

Schedule your live demonstration of FTMaintenance CMMS today

Schedule Demo