This is the documentation page for the Bolted Flange Design module. You'll find here everything you need to understand how to use our application.
1. Drawing

The Bolted Flange Design module can dynamically generate the flange drawing as the User fill the dimensions fields. It follows the flange types and figures shown in ASME BPVC Section VIII Division 1 Appendix 2[ 1 ]. If there's some inconsistency in the dimensions, an red warning will be shown instead of the drawing. Fixing the inconsistency will make the drawing to be shown again.
Fig. 1.1 below show an example of flange drawing. For now, only the frontal cross-section and top view will be shown, but we're working to also show the bolts and gasket drawing.
2. Units
For now, only International Unit System[ 2 ] or just SI Units is accepted, but we're working to implement the Imperial Unit System[ 3 ] in the following versions, as it's still used by many countries and companies.
The Table below show the relationship between International and Imperial unit system.
Unit | International | Imperial |
---|---|---|
Temperature | °C | °F |
Pressure | MPa | PSi |
Length | mm | in |
Density | kg/cm^3 | °F |
Volume | m^3 | ft^3 |
Weight | kg | lb |
Force | N | lbf |
Area | mm^2 | in^2 |
Moment | N.mm | lbf.in |
3. Fields
Below is a list of all the available fields in the Bolted Flange Design module. Not all fields are shown at once, some fields are unique for some types of flange, as hub fields, that only show for flanges with hub.
Other fields are shown, but can only be edited if certain condition are met, as the material fields, which can only be edited if the User selected the checkbox "Use your own values?".
3.1. Module

Variable | Name | Unit | Type | Description |
---|---|---|---|---|
<none> | Description | <none> | Input | Short description of the part. For example: if designing a Bolted Flange to be connected at the upper part of the vessel, you can simply call if Upper Flange, if there's other flanges in there, you can be even more specific, calling if Upper Left Flange or Upper Gas Flange. Just remember that you'll use the description to identify the part (you can also use its id, but it's usually difficult to remember) |
<none> | Decimal Places | <none> | Select | Number of decimal places to be used in the calculations and results. User can choose between 1 to 4 decimal places (also known as precision). |
<none> | System of Units | <none> | Select | Unit system that will define the units used in all the variables in the calculation. The most known types are Imperial System and International System. Unfortunately we still don't support changing units and the International System will be used as a default. |
3.2. Process

Variable | Name | Unit | Type | Description |
---|---|---|---|---|
<none> | Fluid | <none> | Fluid name, it's optional as it will not be used in any calculation. See Note (2). | |
To | Operating Temperature | °C, °F | Temperature of the vessel when the equipment is in service. It's optional. See ASME BPVC Section VIII Division 1 Nonmandatory Appendix C for suggested methods to obtain the operating temperature of vessel walls in service and also UG-20 for more information. | |
Po | Operating Pressure | MPa, PSi | Pressure of the vessel when it's in service. It's optional and will not be used in any calculation. | |
Td | Design Temperature | °C, °F | Maximum expected temperature in the vessel in normal operation. See UG-20 for more information. | |
Pd | Design Pressure | MPa, PSi | Maximum expected pressure in the vessel in normal operation. See UG-21 for more information. |
3.3. Dimensions
Variable | Name | Unit | Type | Description |
---|---|---|---|---|
<none> | Flange Type | <none> | types according to Figure 2-4 from ASME BPVC Section VIII Division 1. Although 24 types are shown in the Code, we only support 22, the 2 remaining are Flanges with Nut Stops. The User will notice that some types have exactly same information (including drawing) as other types (it's the case of Fig. 2-4(9) and Fig. 2-4(10)) and we did it because we wanted to stay true to the Code, letting the User selected the figure used in the project. Other softwares decided to only let the User choose between Integral and Loose type of flanges, without mentioning the figures. | |
<none> | Flange Construction | <none> | construction type according to Figure 2-4. It can be either Integral or Loose. There are Optional types (Figures 2-4(8) to 2-4(11)) which let the User selected if it'll be calculated as Integral or Loose. | |
B | Flange Inside Diameter | mm, in | inside diameter of flange. When it's less than 20∗g1 it will be optional for the designer to substitute B1 for B in the formula for longitudinal stress SH | |
A | Flange Outside Diameter | mm, in | Outside diameter of the flange, it's the biggest dimension of it. | |
t | Flange Thickness | mm, in | Thickness of the flange, the most important variable. | |
tn | Nozzle Wall Thickness | mm, in | Nominal thickness of shell or nozzle wall to which flange or lap is attached | |
g0 | Thickness of Hub at Small End | mm, in | Thickness of the part of the hub that is farther from the flange. | |
g1 | Thickness of Hub at Back of Flange | mm, in | Thickness of the part of the hub that is closest to the flange. | |
h | Hub Length | mm, in | Hub length, used only in flange types that have hub, as Fig. 2-4(8a) and Fig. 2-4(10a). | |
faceID | Flange Face Inside Diameter | mm, in | Inside diameter of the face used to seat the gasket. | |
faceOD | Flange Face Outside Diameter | mm, in | Outside diameter of the face used to seat the gasket. In the drawing it's shown as a raised face but, in fact, it can be a flat face, as shown in the Figure 2-4. | |
pd | Inside Pipe Diameter | mm, in | Dimension only used when User selected flange types that have pipes attached (Fig. 2-4(2), 2-4(2a), 2-4(3), 2-4(3a), 2-4(4), 2-4(4a), 2-4(4b) and 2-4(4c), 2-4(8), 2-4(8a), 2-4(9), 2-4(9a), 2-4(10), 2-4(10a) and 2-4(11)). The sole purpose of this dimension is to be used to draw the pipe inside de flange, it will not be used in any calculation, so the pipe required thickness will not be calculated. If the User want to calculate it, use the Shell & Head Design or use a standard pipe. | |
tl | Lap Outside Diameter | mm, in | Dimension only used when User selected lap flange types (Fig. 2-4(1), and 2-4(1a)) | |
corr | Corrosion Allowance | mm, in | It's up to the designer engineer to define a corrosion margin or corrosion allowance for the project (see UG-25 from ASME BPVC Section VIII Division 1). Our application will show the maximum allowable pressure for both conditions (new and corroded) | |
<none> | Use B1 instead of B | <none> | As described in the variable B above, when B is less than 20*g1, the user can use B1 instead of B for longitudinal stress (SH) |
3.4. Bolting
Variable | Name | Unit | Type | Description |
---|---|---|---|---|
<nome> | Do you want to insert your own values? | <none> | When checked, will let User edit the fields Bolt Outside Diameter and Bolt Root Area and will hide the fields Standard and Bolt Size and Class. | |
<none> | Standard | <none> | List of standard codes for bolts and screws. When a code is selected, the Bolt Size and Class field will load all available sizes for the selected code. | |
<none> | Bolt Size and Class | <none> | List of all available bolt or screw size for the selected standard code. | |
C | Bolt Circle Diameter | mm, in | Circle where bolts will be located. | |
BOD | Bolt Outside Diameter | mm, in | Outside diameter of the bolt (do not get confused with root diameter). This field is automatically filled when User select a bolt size from Bolt Size and Class field. | |
BA | Bolt Root Area | mm^2, in^2 | Root area of the bolt (don't use bolt outside diameter to find its area). This field is automatically filled when User select a bolt size from Bolt Size and Class field. | |
N | Number of Bolts | <none> | It's a good practice to use multiple of 4 as the number of bolts but the application will allow any integer (decimal not acceptable). |
3.5. Gasket
Variable | Name | Unit | Type | Description |
---|---|---|---|---|
<none> | Select Gasket from Database? | <none> | ||
gt | Gasket Thickness | mm, in | ||
GID | Gasket Inside Diameter | mm, in | ||
GOD | Gasket Outside Diameter | mm, in | ||
m | Gasket Factor | <none> | ||
gy | Gasket or Joint Surface Unit Seating Load | MPa, psi | ||
ff | Flange Facing Sketch (Table 2-5.2) | <none> | ||
ffc | Column from Table 2-5.2 | <none> |
3.6. Material
Variable | Name | Unit | Type | Description |
---|---|---|---|---|
<none> | Is the Material Normalized? | <none> | ||
<none> | Use your own values? | <none> | ||
<none> | Material Name | <none> | ||
Suf, Sub | Tensile Strength at Design Temperature | MPa, psi | ||
Syf, Syb | Yield Strength at Design Temperature | MPa, psi | ||
Emdf, Emdb | Elastic Modulus at Design Temperature | MPa, psi | ||
Sf, Sb | Allowable Stress at Design Temperature | MPa, psi | ||
Saf, Sab | Allowable Stress at Ambient Temperature | MPa, psi | ||
mdf, mdb | Material Density | kg/m^3, lb/ft^3 | ||
<none> | Group Number | <none> | ||
<none> | P-Number | <none> | ||
<none> | P-Number Thickness | mm, in | ||
<none> | External Pressure Chart | <none> | ||
<none> | UCS-66 Curve | <none> |
3.7. Settings
Variable | Name | Unit | Type | Description |
---|---|---|---|---|
mdmt | Minimum Design Metal Temperature | °C, °F | ||
<none> | Show factors calculation? | <none> | Show flange factors equations according to Table 2-7.1 and its results in the results page. As there's 45 equations, the results page and the calculation report can get quite long, so we advice you to show it only if needed (for checking or when requested by Customer) | |
<none> | What Test specification should be used? | <none> | Select the type of test that will be performed in the pressure vessel. It can be according to UG-99(b), UG-99(c) or UG-100. Each option have it's own equation, so you can't calculated according to UG-100 and perform the test according to UG-99(b). | |
<none> | Disable sharing of this Module? | <none> | When set to Yes, you'll be able to share this Module/Part with other Users and they can request access to it. You can also change this option at the Project Management module. |
4. Messages
The Module will show messages in the results pages when needed, these messages can be either warnings or info.
4.1. Warnings
If there's any error in the calculation a red warning message (see Fig. 4.1) will be shown in the results page. The warning will have information regarding the error to help User fix it and, if the GoTo link is clicked, the equation with error will be shown.

The User will still be able to save the Module even though there's a warning message. We decided to keep this way because, sometimes people don't want to fix things right away or wan't to let other people deal with it (just share the Module with other User using our Project Management module)
4.2. Info
5. Limitations
The version comes with some limitations which are listed below:
- Flange with Nut-Stops (2-12) not available.
- Reverse Flanges (2-13) not available.
- 3D Model not available.