To remove all the face, edge, coaxial, and contact constraints applied to a selected part instance while leaving the instance in its current position, select Instance
Convert Constraints from the main menu bar. The conversion is equivalent to applying a single translation and rotation to the part instance that moves it from its original position to the current position. Any previous constraints no longer appear in the list of features and cannot be restored.
To convert constraints:
From the main menu bar, select InstanceConvert Constraints to convert any existing constraints to the current position.
From the assembly, select the part instance whose constraints you want to convert. You can also click the Instance List button on the right of the prompt area and select the instance from the Instance List dialog box that appears.
Tip:
If you are unable to select the desired part instance, you can change the selection behavior by clicking the selection options tool 
in the prompt area. For more information, see “Using the selection options,” Section 6.3.
The part instance does not move, but ABAQUS/CAE converts any existing constraints to the current position.
You cannot restore the original face, edge, coaxial, and contact constraints.
