To merge a selected group of part instances, select Instance
Merge/Cut from the main menu bar. You can merge the native geometry of parts that you created in the Part module, or you can merge mesh parts. You can also merge selected nodes of an orphan mesh part using the Edit Mesh toolset in the Mesh module; for more information, see “Merging meshed part instances,” Section 13.6.2. You can also cut a selected instance of a native ABAQUS/CAE part using one or more native part instances to make the cut.
The merge or cut operation creates both a new part instance in the assembly and a new part. You can choose to retain the original part instances that you selected, or you can suppress them. For more information, see “Merging and cutting part instances,” Section 13.6.
To merge or cut native geometry part instances:
From the main menu bar, select InstanceMerge/Cut.
Tip:
You can also merge or cut part instances using the 
tool from the Assembly module toolbox. For a diagram of the tools in the Assembly toolbox, see “Using the Assembly module toolbox,” Section 13.8.
ABAQUS/CAE displays the Merge/Cut Instances dialog box.
Enter the name of the part that will be created by the operation.
Select the type of operation.
To merge the geometry of native part instances, choose Merge and Geometry.
To merge the meshes of part instances, choose Merge and Mesh.
To cut part instances, choose Cut geometry.
By default, ABAQUS/CAE keeps only the new part instance that results from the operation and suppresses the original part instances that were merged or cut. Toggle off Suppress original instances if you want to retain the original part instances. After you complete the Merge/Cut operation, you can use the Feature Manager to suppress or resume the original part instances, regardless of the setting you choose in the Merge/Cut Instances dialog box.
If you chose a Merge operation, do the following:
By default, ABAQUS/CAE removes the boundaries between intersecting part instances. If you want to retain the boundaries between intersecting part instances, choose Retain from the bottom of the Merge/Cut Instances dialog box. The effect of removing and retaining the boundaries is shown in Figure 13–24.
Click Continue.
Select the part instances to merge. You can use a combination of [Ctrl]+Click and [Shift]+Click to select multiple part instances. You can also click the Instance List button on the right of the prompt area and select the instances from the Instance List dialog box that appears.
Tip:
If you are unable to select the desired part instances, 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.
Click mouse button 2 to indicate that you have finished selecting part instances.
ABAQUS/CAE merges the selected instances and creates a new part instance and a new part.
If you chose a Cut operation, do the following:
Click Continue.
Select the part instance to be cut. You can select only one part instance.
Select the part instances that will make the cut. The part instances must touch or overlap the part instance to be cut.
Click mouse button 2 to indicate that you have finished selecting part instances.
ABAQUS/CAE cuts the selected instance and creates a new part instance and a new part.
To merge mesh part instances:
From the main menu bar, select InstanceMerge/Cut.
Tip:
You can also merge part instances using the tool from the Assembly module toolbox. For a diagram of the tools in the Assembly toolbox, see “Using the Assembly module toolbox,” Section 13.8.
ABAQUS/CAE displays the Merge/Cut Instances dialog box.
Enter the name of the part that will be created by the operation.
From the Merge/Cut Instances dialog box, choose Merge and Mesh.
By default, ABAQUS/CAE keeps only the new orphan mesh part instance that results from the operation and suppresses the original part instances that were merged. Toggle off Suppress original instances if you want to retain the original part instances. After you complete the Merge/Cut operation, you can use the Feature Manager to suppress or resume the original part instances, regardless of the setting you choose in the Merge/Cut Instances dialog box.
Choose the method that ABAQUS/CAE will use to merge nodes:
Boundary only. By default, ABAQUS/CAE merges the meshes only along their boundaries. As a result, ABAQUS/CAE does not check for duplicate nodes in the interior of the parts, and this speeds up the merging process. You should retain this default setting if the part instances intersect at only a common face.
All. Merge all the nodes in the selected part instances.
None. Merge the part instances into a single part instance but retain the original nodes.
If you choose to merge All nodes, by default ABAQUS/CAE removes elements that have the same connectivity as an existing element. Toggle off Remove duplicate elements to retain duplicate elements.
Enter the Node merging tolerance. ABAQUS/CAE deletes nodes that are closer than the specified tolerance and replaces them with a single new node. The location of the new node is the average position of the group of nodes that were merged into the new node.
Click Continue.
Select the part instances to merge. You can use a combination of [Ctrl]+Click and [Shift]+Click to select multiple part instances. You can also click the Instance List button on the right of the prompt area and select the instances from the Instance List dialog box that appears.
Tip:
If you are unable to select the desired part instances, 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.
Click mouse button 2 to indicate that you have finished selecting instances.
If the value that you entered for the Node merging tolerance is too large, ABAQUS/CAE may detect duplicate nodes from the same element. ABAQUS/CAE will not merge nodes from the same element, but the large tolerance can result in a distorted mesh. If the Node merging tolerance is too large, ABAQUS/CAE asks if you want to continue merging the part instances.
Click Yes to continue.
Click No to cancel the merging procedure.
ABAQUS/CAE highlights in magenta any nodes that will be merged and asks if you wish to proceed.
Click Yes to continue.
Click No to cancel the merging procedure.
ABAQUS/CAE merges the nodes that are closer than the specified tolerance and replaces them with a single new node. The location of the new node is the average position of the group of nodes that were merged into the new node. If no nodes are closer than the specified tolerance, ABAQUS/CAE asks if you want to cancel the procedure or merge the selected instances into a single part instance.
Click Highlight merged nodes from the prompt area to see the resulting merged nodes. ABAQUS/CAE asks if you want to accept the merged mesh.
Click Yes to continue.
Click No to cancel the merging procedure.
ABAQUS/CAE merges the selected instances and creates a new part instance and a new part. You can use the Mesh gaps/intersections tool in the Query toolset to check for any small gaps and incompatible faces resulting from the merge operation. For more information, see “Obtaining general information about the model,” Section 45.2.2.
If you previously created node or element sets that include nodes or elements that are deleted by the merge operation, ABAQUS/CAE updates your sets accordingly.
