The IPROHoles - NPT Holes tool is used to create NPT Hole (National Pipe Thread) in the scene. This dialog box is displayed every time you drop the NPT Holes tool in the scene or when you edit an existing NPT hole.

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Settings

The items included in this box enable you to save the current setting of the hole. This enables you to recall them quickly in future sessions. The buttons included in this section enable you to save, remove or apply any saved setting.

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Parameters

• Normative - This option is used to select the standard diameters in inches or millimeters.
• Hole Diam. - This option is used to select the required diameter for the hole.
• Hole Depth - This option is used to insert or to select the depth of the hole. With the option at right you can see the measurement in inches or millimeters.
• Taper Angle - This option shows the draft angle of the hole.
• Thread Pitch - This option shows the Thread Pitch of the hole. To enable this item, you have to check the Edit option.
• Callout - If you want assign the callout in the 2D drawing, check this option.

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The data structure behind NPT Holes

All the data files related to NPT hole are placed in the folder ..\Norme\Holes\

This is the list of the files contained in the folder and a description of their structure:

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NPTRules.ini - NPTDiameters.dat - NPTDiametersMM.dat

These files contain the standard diameter values (in inches and millimeters) related to NPT normative.

## ========================================================
## * IRONPROXT -  PARAMETRIC LIBRARY  -  Fronema Srl *
## ========================================================
##
# Name   |  Data File           |Callout| 0=MM 1=Inches
NPT_IN | NPTDiameters.dat |  NPT |  1
NPT_MM | NPTDiametersMM.dat |  NPT |  0

## ===================================================================
## * IRONPROXT -  PARAMETRIC LIBRARY  -  Fronema Srl *
## ===================================================================
##                
## NPT Thread Hole Diameters                
## separator field is TAB
## Units are in inches
##          
## Insider_Diam NominalSize  Pitch1   Pitch2  Length    TaperAngle
0.337 1/8 0.03571  0      0.2441 1.79
0.451 1/4 0.05262  0      0.3701 1.79
0.589 3/8 0.05262  0      0.3812 1.79
0.734 1/2 0.05262  0      0.5000 1.79
0.950 3/4 0.07143  0      0.5551 1.79
1.193 1 0.07143  0      0.6378 1.79
1.534 1 1/4 0.09091  0      0.7284 1.79
1.766 1 1/2 0.09091  0      0.7284 1.79
...
...

## ===================================================================
## * IRONPROXT -  PARAMETRIC LIBRARY  -  Fronema Srl *
## ===================================================================
##  
## NPT Thread Hole Diameters                
## separator field is TAB
## Units are in mmillimeters
##        
## Insider_Diam NominalSize  Pitch1   Pitch2  Length    TaperAngle
8.566           1/8          0.9071   0       6.2       1.79
11.445          1/4          1.3368   0      9.4       1.79
14.950          3/8          1.3368   0       9.7       1.79
18.631          1/2          1.3368   0       12.7      1.79
24.117          3/4          1.8143   0       14.1      1.79
30.291          1            1.8443   0       16.2      1.79
38.952          1 1/4        2.3091   0       18.5      1.79
44.845          1 1/2        2.3091   0       18.5      1.79
...
...

The structure of the files are self-explaining.

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