This equation is intended to be used as a vCalc equation-in-equation (EiE) to performs a cell look-up in the data set: Pipe Schedules (1/8 to 48). The data accessed by this NPS Lookup equation represents the Nominal Pipe Size (NPS) North American standard for pipes and the corresponding Schedules which specify wall thickness.
To access a cell in the table, which contains a wall thickness value, the equation performs a look-up by NPS and Schedule.
Note that some Schedules do not list wall thickness values for some pipes sizes. This equation will return the string "Table Cell Not Populated" for those cases where the schedule does not have a value for a specific pipe size.
"Nominal Pipe Size (NPS) is a North American set of standard sizes for pipes used for high or low pressures and temperatures.[1] Pipe size is specified with two non-dimensional numbers: a nominal pipe size (NPS) for diameter based on inches, and a schedule (Sched. or Sch.) for wall thickness. NPS is often incorrectly called National Pipe Size, due to confusion with national pipe thread (NPT). The European designation equivalent to NPS is DN (diamètre nominal/nominal diameter/Durchmesser nach Norm), in which sizes are measured in millimetres.[2] The term NB (nominal bore) is also frequently used interchangeably with NPS."1
Note that the NPS is a descriptor for a pipe size, denoting "nominal" diameter. However, as the table shows the actual outside diameter (OD) in most cases is not the same as the NPS designation.
The schedules selectable for each NPS size are:
5S, 5, 10S, 10, 20, 30, 40 & Std, 40, 60 80s & EH, 80 , 100, 120, 140, 160, XXH