Turn Rule

This section provides a brief overview of the Turn Rules tables.

The Turn Rules table allows you to manage a routable turns. It is composed of input columns referring to the Reference Dimension table, and output columns that define the authorized values for the Bend Radius and if a specific part should be used to realize the turn (specific elbows, nothing...).

The Bend Radius column contains the bend radius to be applied. If it is equal to 0mm or Unset, the combination of Bend Diameter and Diameter Factor gives the value of the Bend Radius with the following formula : "Bend Radius"="Bend Diameter"*"Diameter Factor". The value inside the Nominal Bend Radius is used to value the corresponding attribute on objects. It is only informative and not used by the app.

Note that the Bend Radius column represents the Inner Bend Radius in case of non-circular shapes.

In Data Setup, this table should be assigned to:

• when using file-based tables, the Turn Rule item in the resource table of HVAC Design Resources.
• when using Engineering Specification objects, a specification in the resource table of HVAC Specification Resources.

This section describes the customization options of the Turn Rule tables.

The following table describes the meaning of each column.

Parameter	Type	Importance	Input / Output	Description
Standard	String	Required	Input	Used for filtering.
Equivalent Diameter	String	Required	Input	Used for filtering.
Shape	String	Required	Input	Used for filtering.
Height	Length	Required	Input	Used for filtering.
Width	Length	Required	Input	Used for filtering.
Material	Material	Optional	Input	Used for filtering.
Material Category	String	Required	Input	Used for filtering.
Bend Radius	Length	Optional	Output	Enter value required for each standard, material and size.
Diameter Factor	Real	Optional/Required	Output	Used for calculation if DS_BendRadius does not contain a value.
Bend Diameter	Length	Optional/Required	Output	Used for calculation if DS_BendRadius does not contain a value.
Nominal Bend Radius	String	Optional	Output	Provides information only. Displayed in properties of an object and in Turn Rules dialog box.
Physical Part Subtype	String	Optional	Output	Part Subtype to use to create the bend.

If there is no value (0) in DS_BendRadius, then the app tries to determine a bend radius value by multiplying DiameterFactor by BendDiameter.

As an example, for Row 2 in the table above, the diameter factor (2) multiplied by the bend diameter (0.25) will be the bend radius.

This section explains where to find the sample resource file.

The default location of XXX_XXX_TurnRules.xls is:

..\startup\EquipmentAndSystems\Duct\Specification\

and then the relevant specification, such as SS150R.