Parts and assets · Lesson 17 · Approx. 7 minutes including practice
Bills of materials
A BOM describes the approved items and quantities for a defined product structure. State whether quantities are per assembly, machine or kit. Reconcile identifiers with drawings and avoid using descriptions as the only key.
Step 1: Product structure
A documentation workflow, not an equipment operating sequence. Animation starts only when you choose Play.
Define quantity in context
A BOM is meaningful only when the assembly level, configuration and quantity basis are stated. Four bolts per subassembly does not mean four bolts per machine if the machine contains three such subassemblies. Keep part identifiers separate from descriptions and supplier references. Confirm how kits, consumables and optional items are represented. A spreadsheet total that looks reasonable can still mix incompatible quantity bases and result in over-ordering or shortages.
Prepare and check the work
Use a controlled structure and reconcile it with the drawing item balloons and approved product definition. Check duplicates by identifier, not by description alone. Distinguish a manufacturing BOM from a service parts list; the service team may order a complete purchased unit where manufacturing records show individual components. When quantities change, identify the affected configuration and obtain approval before propagating the update into purchasing or ERP data.
Worked example · demonstration only
A seal kit is listed as quantity two without stating whether that means two kits per machine or two seals inside one kit. Ask the product owner to define the supply unit and revise the field labels. Do not solve the ambiguity by changing the description alone.
Guided practice and review evidence
Use only a demonstration dataset for this exercise: Create a five-row BOM and verify its parent-child quantities. Before starting, write down the question the finished record should answer and identify the source information you would need on a real job. Keep a separate list of missing inputs. Prepare a first draft, then compare it with the topic-specific checks above. Ask another person to follow your references without explaining them verbally. Record where they hesitate, what information they cannot locate and any different interpretation. Keep a brief review log with four columns: observation, proposed action, responsible reviewer and closure evidence. Revise the example and repeat the information-finding check. Your evidence of completion is the revised demonstration record plus that log, not simply time spent reading. Do not upload client information to the academy or practise on operating equipment.
What good completion looks like
A useful result can be understood by someone who did not prepare it. They can identify its purpose, applicable item, source and review status, and they can distinguish confirmed information from unresolved questions. Pay particular attention to this failure mode: An item used twice in two subassemblies may require a different total at machine level. Check the output in the format the recipient will use. A native file, spreadsheet and exported PDF can expose different problems. Keep the source revision and the issued output linked, and record any limitations of the handover. On a real project, follow the customer's authorised checking and approval arrangements before the information is used. The knowledge check below tests understanding of this lesson; it does not assess practical competence or authorise regulated work.
Practical workflow
- Establish the source: identify the approved input, document revision and person responsible for its technical content. Record missing information as an open question.
- Prepare a small representative example before applying the approach to a whole project. Check identifiers, units, references and the intended reader’s needs.
- Ask the nominated reviewer to check technical meaning. Capture the response, resolve comments and issue only under the agreed document-control process.
Review checklist
- Can another reader identify the source and applicable revision?
- Are assumptions and unresolved decisions clearly recorded?
- Is there evidence of the required review before issue?
Educational material and demonstration examples. Not accredited training, practical competency assessment or authority to perform regulated work. Use current approved sources and your responsible technical authority on real projects.