Miter joint - is two pipes welded together at an angle to each other without using a bend. A miter joint can be inserted for angles of up to 45 degrees. Miter joints are used for flexibility and stress analyses.
Usually used for modelling of Widely-Spaced Miter bends or for single miter joints.
To insert a miter joint, select the desired node and use the menu option: Insert > Insert Bend > Miter Joint (Widely-spaced)
or use the 
toolbar
icon.