HVAC Autofitting Preferences

Used to set preferences to standard placement settings and applied as default when placing fittings. It defines common settings for fittings applied automatically while routing. The preferences settings can be done to major HVAC fittings including Elbows, Branches and Settings.

Accessed from:

Ribbon: Building Systems Design > Mechanical > Mechanical Systems > AutoFitting Settings

The preferences set are stored in the system and such properties get applied when placing fittings, say in routing. The settings such as radius, throat lengths and number of segments for elbows, divergence or convergence angles for transitions, and use of a particular take-offs, tees and crosses for branch lines. They are provided via graphical interface allows you to define standard placement settings. The preferences set in the HVAC Autofitting Preferences dialog are stored in an XML file. The default values however can be restored as required.

Setting

Description

Save

Saves the currently set preferences settings in Autofittingoptions.xml file located in the project workspace folder (variable BMECH_AUTOFITTINGOPTIONS_ FILE defines the path). The Save command will overwrite the previous settings saved in the XML file and close the dialog.

Note: The initial settings seen after the Autofitting Preferences dialog is opened are those last saved and those set via the Set as Default AutoFitting Option if any, will precede over until you issue Save command.

Restore Default Settings

Retrieves the default preferences settings, preceding last saved settings, if any. You are prompted to save the retrieved preferences before you close the dialog.

Elbow tab

Sets preferences to all 3 shape elbows.

Rectangular Elbow Settings

Setting	Description
Elbow Options	Sets rectangular elbow type to one of the options: Radius Bend Mitered
No. of Vanes	Sets the numeric value that defines the number of vanes to rectangular elbow.
Vane Type	Sets rectangular elbow type to one of the options: Short — generates a curved vane with a radius defined by the Vanes Size for Radius Bend elbow and an angled vane if Mitered. Long — generates a curved vane extending to the elbow's outlets for Radius Bend elbow and an angled vane if Mitered.
Vane Size	Defines size of vanes; a numeric value uniformly applies to vanes set in the elbow.
Radius Options	Enabled for Radius Bend Elbow Options. Sets radius options to one of the following two: Radius — when set, the RadToDia (Radius to Diameter Ratio) follows changes of Radius. RadToDia — when set, the Radius follows changes of RadToDia. Value — sets the value to the radius option to follow in Autosize.
Throat length (inch)	Enabled for Mitered Elbow Options. Sets the depth to the elbow branch. The value is set in unit inch. (The default value is set such that the connection ends do not overlap.)

Round Elbow Settings

Setting	Description
Elbow Options	Sets round elbow type to one of the options: Stamped Segmented Bend Segmented Bend End Segment Mitered
Radius Options	Sets radius options to one of the following two: Radius — when set, the RadToDia follows changes of Radius. RadToDia — when set, the Radius follows changes of RadToDia. Value — sets the value to the radius option to follow in Autosize.
Segments	Enabled for Segmented Bend End Segment type elbow. Sets the number of segments to elbow.
Segment Angle	Enabled for Segmented Bend type elbow. Sets the angle for segmented bend elbow.
No. Of Miters	Enabled for Mitered type elbow. Sets the number of segments to elbow. Sets the number of miters to the Mitered elbow.

Oval Elbow Settings

Setting	Description
Elbow Options	Sets oval elbow type, only option available is: Segmented
Radius Options	Sets radius options to one of the following two: Radius — when set, the RadToDia follows changes of Radius. RadToDia — when set, the Radius follows changes of RadToDia. Value — sets the value to the radius option to follow in Autosize.
Segments	Sets the number of segments to elbow.

Branch tab

Sets preferences to all 3 shape branch and tee fittings.

Rectangular Branch Options

Setting

Description

Category

Sets rectangular branch category to one of the options:

Takeoff
Lateral
Tee/Crosses

Fittings

Sets branch fittings type to one of the following:

For Takeoffs, the fittings option is set to following:
- Oval Takeoff — the default type oval takeoff is selected in the preferences.
For Lateral, the fittings option is set to the following:
- Oval Tap — the oval tap type is selected in the preferences.
For Tee and Crosses, the fittings option is set to following:
- Oval Tee — the default type tees and crosses are selected in the preferences.

For example, when branch connection is set to Tee, during routing the duct when you add a branched connection, it will recognize the main duct/ cutting duct to match the 'Tee' size with it and in order to maintain the branch connection, it will place a transition after the tee to match the branch duct size. The lateral taps benefit inclined downstream air flow.

Settings tab

Sets the transition angle limit.

Transition Options

Setting	Description
Max Angle Limit (Degree)	Sets the angle value to reducer to have a limit in a transition. This controls the conversion angle (supply to return sides angle) will automatically compute the length.

Ogee Options

Setting	Description
Max. Sheet Width	Sets a maximum overall inline length of the ogee fitting. The value specified here, refers to the longest flattened component within the ogee (the S-shape). The choices are: `none` 36 inches (914 mm) 48 inches (1219 mm) 60 inches (1524 mm) Note: Selecting `none` removes any restriction on the maximum sheet width.

Angle Stop Options

Setting

Description

ACS Angle Stops

Toggle ON to set the desired angle stop values.
Enter the desired angle stop values. It allows maximum five entries.
Fittings are displayed dynamically while autorouting when ACS Angle Stops is turned on.

Note: For each defined angle, it highlights the guideline(sticky point) along with the dynamic fittings display.

Important: If required angle stop values are set and toggled on through autofitting preferences dialog, then any other angle value entered in accudraw angle, during autorouting would not work.

Note: The customization to autofitting options data in active dataset's data folder by manipulating externally will also effect in Autofittingoptions.xml.

Key-in: mdl load Bentley.Building.Mechanical.AutoFittingOptions.dll