Additional Windchill Capabilities > Windchill Aerospace and Defense > Administration and Configuration > Managing Parts > Defining Part Subtypes and Relationship Constraints
  
Defining Part Subtypes and Relationship Constraints
The five base part types shown in the image below are included with the Windchill Aerospace and Defense Module (WADM) and appear in the Type and Attribute Management utility:
For more information on the base types, see Configuration Management Objects: Windchill Parts.
Part Subtypes
For each base part type included with WADM, a corresponding subtype is provided to define how the system handles the parts assigned to those types. You can use these out-of-the-box subtypes from the Configuration Management Objects: Windchill Parts topic or create your own subtype under the base type.
Although not required, it is recommended that a new part subtype is assigned a structure-level attribute that corresponds to the base part type that is its parent type. For example, a new part subtype of the Base Configuration Item type should be assigned a Configuration Item structure-level property value. Additionally, relationship constraints must be defined for a new subtype.
For detailed steps on creating a subtype, see Creating a New Subtype. Additionally, consider the following for WADM:
• If you change the Structure Level property, all existing instances of the part type are affected by the change.
* 
You cannot change the Structure Level property of a subtype if there are relationship constraints specified for it.
• Set the Instantiable attribute to Yes to allow new parts of the subtype to be created.
• Set the Subtypeable attribute to Yes if you want to create a structure level and not a subtype for an actual part. Subtypes that are specified as being subtypeable are not instantiable, meaning that they are not available from the Type menu in the New Part window. Only parts with a blank Structure Level property value can be subtypeable. This means that if you are creating a configuration item, design solution, link object, or lower level part subtype, the Subtypeable property value must be No.
• Configure access control rules so that users cannot revise part subtypes with structure-level properties of Configuration Item or Link Object.
For more information, see section Structure Level Property in Configuration Management Objects: Windchill Parts.
Defining Relationship Constraints
Use the Type and Attribute Management utility to define relationship constraints.
The part-usage relationship constraints specify the valid parent-child part types for part usage links. By default, the Windchill Aerospace and Defense Module (WADM) delivers a set of part-usage relationship constraints for the out-of-the-box part subtypes. For more information, see Configuration Management Objects: Windchill Parts.
If you create new part subtypes, you must define relationship constraints to define parent-child relationships between new part subtypes. These relationship constraints must have structure-level properties that work within the system definitions. Unless otherwise specified, relationship constraints can be specified allowing one or more child types for a part subtype, as long as the structure-level property of all child types is allowed according to the following table:
Configuration Item-Design Solution (CI-DS) Configuration
Structure Level Property of Parent
Allowed Structure Level Property of Child
Configuration Item1
Design Solution
* 
Multiple child subtypes with a Design Solution structure-level property can be defined for a Configuration Item subtype.
1 If you create a new part subtype with a Configuration Item structure-level property, you must also define a relationship constraint between the new configuration item and a valid change directive. For more information, see Defining Relationship Constraints for Change Objects.

Configuration Item-Link Object-Design Solution (CI-LO-DS) Configuration
Structure Level Property of Parent
Structure Level Property of Child
Configuration Item1
Link Object2
* 
Only one child subtype with a Link Object structure-level property can be defined for a configuration item. No other subtype can be defined as a child for the Configuration Item subtype.
Link Object
Design Solution
1 If you create a new part subtype with a Configuration Item structure-level property, you must also define a relationship constraint between the new configuration item and a valid change directive. For more information, see Defining Relationship Constraints for Change Objects.

2 A Link Object structure-level property can be assigned only if the system is configured to employ the link object. For more information, see Configuring the System to Employ the Link Object.