---
alias: user-guide-special-collapse-material
description: "This documentation details a process for merging materials within a system"
---

# Special Collapse Material

:lock: Material.**SpecialCollapse**

## Overview

This operation is used to collapse **Material**, that is, to merge the Sub-Material(s) back into a Parent **Material**. This operation is similar to Collapse **Material**, except that the Sub-Material must not be a part of the same **Product**.

## Setup

No special setup is required other than to meet the preconditions of the transaction.

## Preconditions

* The Main **Material** and Sub-Material are Active, not On Hold and not In Transit.
* To be collapsed, the Sub-Material must belong to the same Main **Material** and must have the same Facility, Type, Step, Flow Path and Flow.  
* When the collapsed Sub-Material quantity is placed in the same container/position as the Main **Material**, and the associated **Container** has Capacity Validation Mode set to Units, it must be ensured:
    * The Capacity Per Position of the **Container** can hold the Main **Material** and the additional Sub-Material quantity - whether Primary or Secondary, as defined in the Capacity Units of the **Container**.
* If the Main **Material** or Sub-Material are associated with a Production Order, the Production Order must not be Closed.

## Preconditions for Bulk

* In addition to the preconditions mentioned above, all Sub-Materials must:
    * Have the same Parent **Material**.

## Sequence of Steps

### Step 1

1. Select the **Special Collapse** button.
2. Verify the **Material** information.
3. Select the **Sub-Material(s)** to be collapsed by choosing the corresponding case.
4. Optionally, enter a comment.
5. Select **Special Collapse** to complete the operation.

![Screenshot showing a UI with options for Special Collapse, including "Material" and "Sub: Material(s) to Be Collapsed".](images/special_collapse.png)