Required Quantity
Required Build Quantity¶
When a new Build Order is created, the required production quantity of each component part is calculated based on the BOM line items defined for the assembly being built. To calculate the required production quantity of a component part, the following considerations are made:
Base Quantity¶
The base quantity of a BOM line item is defined by the Quantity field of the BOM line item. This is the number of parts which are required to build one assembly. This value is multiplied by the number of assemblies which are being built to determine the total quantity of parts required.
Required Quantity = Base Quantity * Number of Assemblies
Attrition¶
The Attrition field of a BOM line item is used to account for expected losses during the production process. This is expressed as a percentage of the Base Quantity (e.g. 2%).
If a non-zero attrition percentage is specified, it is applied to the calculated Required Quantity value.
Required Quantity = Required Quantity * (1 + Attrition Percentage)
Optional
The attrition percentage is optional. If not specified, it defaults to 0%.
Setup Quantity¶
The Setup Quantity field of a BOM line item is used to account for fixed losses during the production process. This is an additional quantity of the part which is required to ensure that the production run can be completed successfully. This value is added to the calculated Required Quantity.
Required Quantity = Required Quantity + Setup Quantity
Optional
The setup quantity is optional. If not specified, it defaults to 0.
Rounding Multiple¶
The Rounding Multiple field of a BOM line item is used to round the calculated Required Quantity value to the nearest multiple of the specified value. This is useful for ensuring that the required quantity is a whole number, or to meet specific packaging requirements.
Required Quantity = ceil(Required Quantity / Rounding Multiple) * Rounding Multiple
Optional
The rounding multiple is optional. If not specified, no rounding is applied to the calculated production quantity.
Example Calculation¶
Consider a BOM line item with the following properties:
- Base Quantity: 3
- Attrition: 2% (0.02)
- Setup Quantity: 10
- Rounding Multiple: 25
If we are building 100 assemblies, the required quantity would be calculated as follows:
Required Quantity = Base Quantity * Number of Assemblies
= 3 * 100
= 300
Attrition Value = Required Quantity * Attrition Percentage
= 300 * 0.02
= 6
Required Quantity = Required Quantity + Attrition Value
= 300 + 6
= 306
Required Quantity = Required Quantity + Setup Quantity
= 306 + 10
= 316
Required Quantity = ceil(Required Quantity / Rounding Multiple) * Rounding Multiple
= ceil(316 / 25) * 25
= 13 * 25
= 325
So the final required production quantity of the component part would be 325.
Calculation
The required quantity calculation is performed automatically when a new Build Order is created.