Context

in some cases you want that some points of your tube routing is constained ("slave") by other external contextual element

here is the method to do it

Videos

Following videos illustrates how to route a pipe and to create "Lock" node that will not be any more free for manipulation with 3D piping manipulator. 

• Use "Add node Manipulator"
• It require to activate option "Keep link with Selected object"

This node can be modify afterward only by moving the reference contextual element

Note:

This method is working only if the selected 3D point is in another part than the tube itself