Where I came from, a 'Parts List' was associated with a particular item and included the parts needed, which could include any sub-assemblies as single items, to assemble someething to what was shown on the Drawing/Specification that the 'Parts List' was being referenced by.
As for a 'Bill of Material', that was a complete list of all of the parts needed to manufacture a particular finished product. And depending on how options and exceptions were handled, this BOM may or may not be a roll-up of all of the 'Parts Lists' of the sub-assemblies that made up the final product. Also there could be different types of BOM's. For example, if many of the parts were manufactured in-house, there might be a 'Manufacturing Bill of Material' which could include raw material and even items consumed during manufacturing such as welding rod/wire, expendable tooling, paint, adhesives, etc, which might not be explicitly listed in the 'Product Bill of Material'.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA Siemens PLM: UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
In most industries the terms are interchangeable. For engineering documentation on a US defense program the preferred term is parts list. And with the current trend towards Model Based Definition engineering practices (ie. no drawings), the parts list is usually part of a document that includes general/flag notes and any application/effectivity data.
Since a "parts list" often includes bulk materials (like paint, adhesive, sealants, etc.) that are used to produce the part/assembly, or when a "parts list" for a machined component only consists of a single entry describing the raw material used to make the part, a more correct term might be "parts and materials list". But as racookepe1978 notes, ultimately what matters is whatever your company or customer prefers to use.
As I noted above, US DoD contracts usually require a very specific format for parts lists. It is usually in the form of an Indentured Parts List (IPL), where the line of parts used at the next assembly are indentured from the line of the next assy level. The IPL usually is structured to match the contract Work Breakdown Statement (WBS) and the contract Statement of Work (SOW) that defines the products that must be delivered.
Indentured, because the list is, in fact, indented, but also, sub-assemblies are bound (indentured) to the next higher assembly.
Typically an IDL is just a list of drawings. Our BOM usually covers the quantities required to build the system, and the the procurement details, like price and delivery.
TTFN
faq731-376
Need help writing a question or understanding a reply? forum1529
Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
To illustrate why you need to clarify what YOUR company needs - WITH your boss, NOT with us! - is easy to show. An assembled single flange requires 16 1/2 inch stainless steel nuts, but you have 8 flange assemblies in 4 "units" contracts going to one customer at one site, and 2 units going to the same customer at a different site.
how many nuts are on the drawing for one flange subassembly?
How many nuts do you buy per unit?
How many are purchased by your company?
How many are charged to each customer and each customer's job order?
I can think of one other example were "Bill of Materials" might be more correct than "Parts List". What about the drawing for a laminated composite part? The plies used are materials rather than parts, right?
