Default for Valves / Instruments that have their end type set in ValveBW,
ValveCP etc to be dimensioned to their centre point.
For Valves / Instruments that have their end type set in ValveBW, ValveCP
etc and have a bore equal to or less than the value set to be dimensioned
to their centre point. Value is in 1/16ths of an Inch, or mm's, depending
upon the bore units, e.g. 32 x 1/16ths is equivalent to 2” bore.