Workshop Inventory

BOM explosion is the process of taking a finished product and recursively expanding its Bill of Materials to determine the total quantities of all required components.

It converts:

Build 10 Finished Units

into:

Raw materials required across all levels

Simple Example (Single-Level)

Product: Widget

BOM:

Widget
 |- Screw x 4
 |- Plate x 2

If you want to build 10 Widgets, BOM explosion calculates:

Screw = 4 x 10 = 40
Plate = 2 x 10 = 20

That is a first-level explosion.

Multi-Level Example (Real Manufacturing)

Widget
 |- SubAssembly A x 2
 |- Screw x 4

SubAssembly A
 |- Chip x 1
 |- Capacitor x 3

If building 5 Widgets, explosion becomes:

Step 1 - First Level

SubAssembly A = 2 x 5 = 10
Screw         = 4 x 5 = 20

Step 2 - Expand SubAssembly A

Chip      = 1 x 10 = 10
Capacitor = 3 x 10 = 30

Final Explosion Output (Flattened)

Screw     = 20
Chip      = 10
Capacitor = 30

Subassemblies are expanded until only leaf components remain.

What Explosion Produces

A flattened requirement list:

{
  product_id: total_required_qty
}

No inventory logic. No purchasing logic. Just structural multiplication.

What Explosion Does Not Do

It does not:

• Check stock
• Create POs
• Create requisitions
• Reserve materials
• Decide make vs buy

It only answers:

If I build X units, how much of everything do I structurally need?

Where It Fits in Your System

In your architecture:

KitPlan
  ->
BOM Explosion
  ->
Required Quantities
  ->
Netting (on_hand - reserved)
  ->
Shortage
  ->
Requisition

Explosion is step 1 of MRP.

Recursive Nature

Explosion must:

• Multiply quantities at each level
• Detect circular references
• Aggregate totals across branches
• Handle optional lines (if supported)

Why It Matters

Without explosion:

• You cannot calculate shortages.
• You cannot know buildable quantity.
• You cannot cost finished goods.
• You cannot execute builds correctly.

It is the core structural operation of manufacturing systems.

Conceptual Summary

A recursive tree multiplication that converts a hierarchical design into a flat material requirement list.

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