When creating a piping family parameter, specify the parameter type in the Parameter Properties dialog.
In the Family Editor, click Create tab
Properties panel 
(Family Types). In the Family Types dialog, under Parameters, click Add. For Discipline, select Piping. For Type of Parameter, select one of the following.
Properties panel (Family Types). In the Family Types dialog, under Parameters, click Add. For Discipline, select Piping. For Type of Parameter, select one of the following. | Name | Description |
|---|---|
| Density | Used to define the density of fluids, used with pressure drop calculations. |
| Flow | The volumetric flow of a fluid. |
| Friction | The pressure drop in pipe due to friction. |
| Pressure | Used to report static, total, and excess pressure in the System Inspector. |
| Temperature | Used in fluid tables to define temperature dependent values. |
| Velocity | The velocity of a fluid in a pipe. |
| Dynamic Viscosity | A measure of a fluid's resistance to flow (also known as absolute viscosity). |
| Pipe Size | Used to control input/output units for pipe. |
| Roughness | Used to determine the friction factor based on the Reynold's number for flow in a pipe. |
| Volume | Used to report the volume of fluid in a piping system. |
| Slope | Used to format the slope of a pipe segment. |
| Pipe Insulation Thickness | Used to format the thickness of insulation on piping components. |
| Pipe Dimension | Used to format the dimensional characteristics of pipe components. |
| Mass | Used for fabrication part weight. |
| Mass per Unit Length | Not used. |
| Fixture Units | A design factor used in the sizing of plumbing systems. |