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BOM Bill of Materials

BOM Bill of Materials · Multi-Version & Alternate Parts

A three-track system of engineering EBOM, process PBOM and manufacturing MBOM; full control over version switching, alternate-part groups, scrap factors, phantom items and shadow items. An accurate BOM is the shared source of truth for MRP, APS, material picking and cost accounting.

3
BOM Forms (EBOM / PBOM / MBOM)
10
Levels of Auto-Explosion
N
Parallel Version Validity Management
Capabilities

Core Capabilities Covering the Full BOM Lifecycle

From engineering drawings to process conversion, from production material usage to cost allocation, BOM data runs through the entire chain

📑 Multi-Version BOM

The same finished product supports N coexisting versions, taking effect precisely by effective date / customer / project; old versions keep tracing historical work orders while new versions only affect newly created ones

🔁 Alternate-Part Groups

Same spec across different brands, batches or emergency substitutes are managed as "primary part + alternate-part group + priority," with substitution suggestions automatically proposed in shortage scenarios

📉 Scrap Factors

Cutting loss, trial-run loss and first-article loss are configured per operation; MRP automatically adds scrap during material calculation, avoiding "enough in theory, short in reality"

🌙 Phantom / Shadow Items

Phantom items aggregate common structures, shadow items are used for cost allocation; MRP skips phantom items straight to base materials, while finance allocates cost by shadow item

📝 ECN Engineering Change

BOM changes go through an ECN approval workflow, with before/after differences automatically compared; once approved, work-order BOM versions switch automatically by effective date

📊 BOM Comparison & Impact Analysis

Tree comparison of two BOM versions makes additions/deletions/changes obvious; when a material changes spec, all affected finished products are listed automatically

mes.shangbangke.com/bom/structure3-track sync
BOM
EBOM / PBOM / MBOM — Flange DN50
DiffSync
PartNameEBOMMBOM
M-1001SS bar stock 3041.2kg1.35kg
M-1002NBR seal ring11
T-2001Turning fixture1 set
P-3001Anti-rust film1

Diffs flagged red · MBOM adds tooling & packaging

EBOM / PBOM / MBOM Synced Across Three Tracks

Engineering produces the EBOM organized "by assembly relationships," process engineers convert it into the PBOM organized "by operation flow," and the shop floor actually produces against the MBOM that "includes tooling, fixtures and scrap." The three BOMs share one source and stay in sync, yet each serves a different stage.

  • EBOM imported directly from PLM/CAD or integrated with SolidWorks / Pro/E / AutoCAD
  • PBOM broken down to operations along the process routing, with each operation's pick list independently visible
  • MBOM includes "production-essential but not on the drawing" materials such as tooling, fixtures, molds, consumables and packaging
  • Differences across the three BOMs are auto-flagged in red, preventing engineering changing the drawing while process lags behind
mes.shangbangke.com/bom/substituteAlternates
BOM
Alternate Group — M-1002 Seal
StockAdd alternate
PriorityPartStockType
PrimaryNBR seal standard0Short
Alt 1NBR seal local1200Equivalent
Alt 2FKM seal800Restricted
Alt 3EPDM temp part300Emergency

Alternate-Part Groups: Stop Shortages from Stopping the Line

Supplier shortages, incomplete batches, urgent rush jobs — in these scenarios "finding a substitute" is a shop-floor norm. Pre-build the substitution relationships into the BOM, and when a shortage hits, the system proposes the solution directly — no need to chase procurement, process and quality every time.

  • Primary part + multiple alternates sorted by priority, classified as "fully equivalent / restricted / emergency"
  • Restricted substitutes note the customer-approved scope (approved only by customer A, requires re-sampling, etc.)
  • MRP automatically decides whether to enable alternates when primary-part stock is insufficient
  • Alternate-usage records are archived for later engineering improvement and supplier evaluation
mes.shangbangke.com/bom/ecnECN-0231
BOM
Engineering Change ECN-0231
ImpactRoute approval
M3 screw → M4
2026-06-01
18 orders
3 orders
Process/QC pending
Keep old version

ECN Engineering Change: Controlled Changes, No Pitfalls

Changing a single screw in a BOM seems trivial, but the impact may span 50 in-transit work orders, 200K of inventory materials and WIP orders at 3 suppliers. The ECN workflow understands the impact before routing for approval, avoiding the "no way back" surprise after a change.

  • An ECN request automatically lists affected work orders, inventory, in-transit procurement and quantities already shipped to customers
  • The change effective date links to work-order start dates; already-started work orders keep the original version
  • OA-workflow integration with multi-level countersigning across engineering / process / quality / procurement
  • The first batch produced after the change is auto-tagged for first-article verification traceability
Use Cases

BOM in Action Across Different Manufacturing Modes

Auto Parts: Multi-Customer Multi-Version

The same bracket supplied to 5 OEMs, each with slight differences in color / printing / packaging — build 5 BOM versions by customer, and orders auto-apply the matching version

Electronics PCBA Alternate Parts

During chip shortages, one out-of-stock MCU can affect all products; with alternate-part groups pre-built with 3 backup specs + customer approval status, you can switch in seconds in a crunch

Machinery: Multi-Level BOM

One machine with an 8-level BOM and 3,000+ parts; after multi-level explosion they hang under the project, with purchased / outsourced / make items each routed to procurement or work orders

Food Process BOM

BOM organized "by recipe," with the recipe containing main ingredients, additives, scrap and by-products; batch traceability strictly archived by recipe version

Related Features

How BOM Connects with These Capabilities

BOM data is the shared source for MRP, work orders, cost and traceability

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