Subitem is the main relationship for bills of materials (BOMs) in Nora IPLM. It connects a parent Item to a child Item in an engineering structure. The child keeps its own managed identity; the connection carries information about its particular use, such as quantity and position.
When to use it
- Use Subitem as the main relationship when building engineering assemblies and BOM structures.
- Use it when an existing part must be reused under another parent, with its own quantity or position in that assembly.
Records and direction
- Relationship type: Structure. Forms a parent-child hierarchy between engineering Items.
- From: the parent Item, such as Pump P-100.
- To: the child Item, such as Seal S-10. Specialized Items can also participate, such as Mechanical Items and Standard Parts.
Information to check
- Quantity and unit of measure describe how much of the child is used in this parent.
- Find number, reference designator, and order help identify or organize the occurrence.
- Instance name, usage method, description, and effectivity information can provide further context where these fields are offered.
How to use it
- Create the relation with drag and drop in a Structure widget: drag the intended child Item onto its parent Item. Select Subitem from the relationship options offered, review the records and connection values, and confirm.
- Alternatively, select the parent Item, choose Connect, and select the existing child with the Subitem relationship.
- You can also copy the child to Clipboard and use Paste on the intended parent in the Structure widget. Select Subitem and choose Create to establish the connection.
- Whichever method you use, inspect the resulting parent structure. Check the child revision and the quantity or position recorded on that use.
Subitem example and questions
One seal definition used in two assemblies
Pump P-100 needs two Seal S-10 parts. Pump P-200 needs one of the same seal. In a Structure widget, drag the existing Seal S-10 record onto each parent and choose Subitem. Record the quantity for each connection.
| Parent Item | Child Item | Quantity |
| Pump P-100 | Seal S-10 | 2 |
| Pump P-200 | Seal S-10 | 1 |
The two assemblies reference the same managed seal definition. Their Subitem connections describe different uses. Changing the quantity under Pump P-100 changes that occurrence; it does not mean the seal definition or the quantity under Pump P-200 should change.
Common questions
Should I create two seal records for quantity two? Use one definition for the same part and record the quantity on the connection. Create another Item only when a distinct engineering definition is needed.
What if the child is already connected? Inspect the existing occurrence first. Confirm whether you need to edit its quantity or position, or whether a separate occurrence is intentional.
What happens if I disconnect it? Disconnect removes the selected parent-child connection. The child Item remains a managed record and may still be used in other structures.
Choosing the relationship
Choose Subitem for a component used in an engineering structure. Use Item – Document for a supporting specification or manual, and Drawing for a managed drawing describing the item.
Further reading
For detailed steps, see the Connect, Paste, Disconnect, and Reverse Where Used command articles. The Item and Standard Part object articles explain the records used in the structure.
