On this page
The engineering BOM, also known as an engineering bill of materials or engineering BOM, defines the product as designed. It’s the list of items, parts, components, sub-assemblies and assemblies in the product designed by engineering.
The engineering BOM is often organized by engineers based on the Computer-Aided Design (CAD) or Electronic Design Automation (EDA) tools used. And for any given product design more than one EBOM may be created. For example, the BOM for the Printed Circuit Board Assembly (PCBA) designed by an electric engineer lists the resistors, capacitors and chips. The BOM for the product as designed by a mechanical engineer includes custom parts and purchased hardware like an lcd, buttons, and screws.
While multiple engineering BOMs may exist, the EBOM is not the only type of bill of material; the manufacturing BOM or MBOM differs from the EBOM in structure and depth.
Manufacturing a product is often compared to that of a recipe. If there’s one missing ingredient or missed step in the baking process the outcome will likely be a complete failure. With an engineering BOM, a missing part or component will drastically impact manufacturing the product without any hiccups. The EBOM is the starting point for any product; the information captured here is handed-off to manufacturing and the completeness — or lack thereof — influences the quality of the product being built.
Capturing the right level of detail in an engineering BOM can prepare the company for success and prevent needless extra work for engineering, manufacturing, sourcing and purchasing in the long run. A complete and accurate engineering BOM enables a smoother transition to manufacturing supporting the new product introduction (NPI) process along the way.
Here’s 3 motives to document the details:
It’s good manufacturing practice to verify first article parts coming off a new tool. With a comprehensive bill of materials, manufacturing will have adequate information to ramp tools for new parts and those parts can also be tested before production fully ramps.
Give manufacturing the right parts and right quantities and they are armed with the information to make better purchasing decisions. They can negotiate with multiple vendors to obtain the most competitive pricing. Getting them the information early in the process also ensures that parts with long lead times are ordered and delivered when they need to be without expedite charges.
The manufacturing department must operate with efficient processes and if they’re handed the correct and complete details on the parts, items and components they won’t be left second guessing. With the right level of detail in the EBOM, extra and unnecessary changes in the manufacturing process can be avoided.
Manufacturing product with wrong information in an engineering BOM can set you back and cause problems down the line. Here’s 3 setbacks of a wrong and incomplete EBOM
If the number of parts or components isn’t correctly listed in an EBOM, for example if 10 screws are documented but 12 are needed to put the product together, purchasing doesn’t have the information to buy the right quantity. With too little inventory of even just one part, builds will be stopped or prevented from starting.
A wrong part captured on the EBOM can mean money wasted on unusable inventory or a build delay while the correct part is on order.
In order to get the product built and out the door, a smooth hand-off from engineering to manufacturing needs to happen. Extra and unnecessary change cycles will ensue if an EBOM is not detailed or stable when transferred to manufacturing.
Engineers are often asked to release designs earlier and earlier even when they’re not ready. They must work hard to pass the right and correct information to manufacturing so their design can become a reality. With a complete and accurate engineering bill of materials, the hand-off to manufacturing will be made much smoother. Manufacturing will be armed with the information to make better decisions, including pricing and lead time options, as well as manufacturing process and logistics choices. When all the details including parts, items, components and quantities are correctly noted in an EBOM disruptive late and last minute changes can be avoided.
Arena, bill of materials and change management software helps product engineers and manufacturers better control their product data. All bill of materials (engineering BOMs and manufacturing BOMs) and product information is stored in a centralized location, allowing engineering and manufacturing to share critical product data more effectively. Arena integrates with CAD and EDA tools eliminating duplicate data entry and ensuring that your product information is always up to date.
©2012 Arena Solutions, Inc. Arena and Arena Solutions are trademarks of Arena Solutions, Inc., Reg. U.S. Pat. & Tm. Off. All rights reserved. Other product and company names are the property of their respective holders. Contact Arena at questions@arenasolutions.com for permission to repost or syndicate this content.
Ready to start? Try Arena free for 10 days. Sign up
