Routing
A Routing is a blueprint of BOM Operations.
A Routing stores all Operations along with the description, hourly rate, operation time, batch size, etc. Creating a Routing for your BOM Operations is useful where repeating Operations are used to manufacture various items. In the latest version of ERPNext, Routing also allows you to specify the sequence of operations through a Sequence ID so that operations are carried out in a specific sequence. You can also have dependencies among operations in such a way that you cannot bypass crucial steps when you're running production.
To display the Routing list, navigate as follows:
1. Prerequisites
Operation: Operations identify single operations in manufacturing. Each Operation should be established before you create a Routing. You can assign details like the default workstation, time consumed, and whether the operation is active or inactive.
Workstation: Workstation is a single location or equipment on which the Operation is currently being carried out. A workstation can have such attributes as working hours, holiday list, rate per hour, capacity, and operating cost. Workstations are utilized to find operating cost when routing and BOM costing.
2. How to Create a Routing
Go to: Routing list, click on New.
Give a name to the Routing.
Enter the Operations into the BOM Operation table:
Select the Operation. The default Workstation will be automatically picked up based on the Operation settings. You can override this manually if needed.
Enter the Hourly Rate to execute this Operation. The Hourly Rate sets the price for each hour to perform the operation on the selected workstation. It can either be derived from the workstation or filled manually.
Enter the Operation Time in minutes. This is the time for processing one batch. In the present version, ERPNext has fractional minutes and also considers setup time separately if it has been set.
Insert the Batch Size, i.e. the number of units handled in this Operation. The Batch Size helps us in cost per unit determination. For example, if the operation duration is 60 minutes and the batch size is 10, then effective time per unit = 6 minutes.
The Operating Cost will be calculated based on the Hourly Rate and the Operation Time. This is so that cost is evenly distributed over the quantity in the batch. The formula used is:
Operating Cost = (((Hourly Rate * Operation Time in Hours) / Batch Size))
In the new version, you can even assign a Sequence ID to each operation. This numeric ID strictly imposes the order of operation execution. In case a Job Card tries to complete a next operation before an earlier operation (based on Sequence ID), the system will throw a validation error, upholding proper workflow compliance.
You can also mark some operations as "Skip Material Transfer" or "Do not Create Job Card" based on the workflow choice. This is used for manual or subcontracted operations that don't require tracking.
Save
Once created, a Routing can be selected in a BOM to obtain the Operations saved in the Routing. The Operations, as well as all the specifics defined such as hourly rate, batch size, time, and cost, will be auto-updated in the BOM. This supports standardization of manufacturing steps on numerous items and maintains costing and planning constant. In ERPNext v15 and onwards, any adjustment in the Routing (such as altering operation time or sequence) can be implemented over all BOMs linked with the same Routing by reloading them.
3. Sequence ID in Routing
Routing Sequence ID enforces the users to complete the operations in succession using Job Card. If a user tries to complete an operation without completing any of its preceding operations based on the Sequence ID, the system raises a validation exception.
In ERPNext version now, each Operation within a Routing has a Sequence ID field. It has a numerical value which indicates the order in which the operations will be carried out. This sequence is used by the system for verifying the correct execution flow during production.
If a Job Card for a higher Sequence ID operation is posted prior to finishing all lower Sequence ID operations, ERPNext will not allow it and display an error message, preventing out-of-sequence completion. This helps maintain tracking of manufacturing steps and maintains production discipline.
Also, ERPNext now has the facility of linking operation dependencies, i.e., one operation can be specifically marked as being dependent on another even if their Sequence IDs are not sequential. This provides more flexibility without compromising control on the sequence of operations. Sequence validation is not only at the completion of job card but also while creating or submitting bulk job cards by workflow actions.