Modules → Shell & Head Design

Shell & Head Design

This is the documentation page for the Shell & Head Design. You'll find here everything you need to understand how to use our application.

We highly advice you to start by reading the Limitations section, because the version 1.0.0 don't fully support ASME BPVC Section VIII Division 1.

1. Types

This application support the following types of pressure vessel shell and head:

Shell

  • Cylindrical

Head

  • Ellipsoidal
  • Torispherical
  • Hemispherical
  • Conical
  • Flat
  • Toriconical

2. Drawing

module-tab
Fig. 2.1. - Drawing

The drawings for the head and shell types are generate dynamically and updated every time the USER change a dimension. After the button Run is clicked, the Results page will be shown and the drawing can no longer be changed (unless the user click in the Back button).

3. Units

For now, only International Unit System[ 1 ] or just SI Units is accepted, but we're working to implement the Imperial Unit System[ 2 ] 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
PressureMPaPSi
Lengthmmin
Densitykg/cm^3°F
Volumem^3ft^3
Weightkglb
ForceNlbf
Areamm^2in^2
MomentN.mmlbf.in

4. Fields

Below is a list of all the available fields in the Module.

4.1. Module

module-tab
Fig. 4.1.1. - Module Tab
Variable
Name
Unit
Type
Required
Description
<none>Description<none>InputYesShort 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>SelectYesNumber 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>SelectYesUnit 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.

4.2. Process

module-tab
Fig. 4.2.1. - Process Tab
Variable
Name
Unit
Type
Required
Description
<none>Fluid<none>SelectNoFluid name, it's optional as it will not be used in any calculation. See Note (2).
ToOperating Internal Temperature°C, °FFieldNoInternal temperature of the vessel when the equipment is in service. 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.
PoOperating Internal PressureMPa, PSiFieldNoInternal pressure of the vessel when it's in service. Will not be used in any calculation.
TdDesign Internal Temperature°C, °FFieldYesMaximum expected internal temperature in the vessel in normal operation. See UG-20 for more information.
PdDesign Internal PressureMPa, PSiFieldYesMaximum expected internal pressure in the vessel in normal operation. See UG-21 for more information.
ToeOperating External Temperature°C, °FFieldNoExternal temperature of the vessel when the equipment is in service.
PoeOperating External PressureMPa, PSiFieldNoExterna pressure of the vessel when it's in service. Will not be used in any calculation.
TdeDesign External Temperature°C, °FFieldYesMaximum expected external temperature in the vessel in normal operation.
PdeDesign External PressureMPa, PSiFieldYesMaximum expected external pressure in the vessel in normal operation.

4.3. Dimensions

4.3.1. Conical Head

module-tab
Fig. 4.3.1.1. - Dimensions Tab, Conical Head
conical-head-doc Fig. 4.3.1. - Conical Head Dimensions
Variable
Name
Unit
Type
Required
Description
<none>Type<none>SelectYesxxx
DInside Diametermm, inFieldYesxxx
hHalf Apex Angle°FieldYesxxx
slSection Lengthmm, inFieldYesxxx
tPlate Thicknessmm, inFieldYesxxx
caCorrosion Allowancemm, inFieldYesxxx
EJoint Efficiency<none>FieldYesxxx

4.3.2. Cylindrical Shell

module-tab
Fig. 2.1. - Drawing
cylindrical-shell-doc Fig. 4.3.2. - Cylindrical Shell Dimensions
Variable
Name
Unit
Type
Required
Description
<none>Type<none>SelectYesxxx
DInside Diametermm, inFieldYesxxx
hHalf Apex Angle°FieldYesxxx
slSection Lengthmm, inFieldYesxxx
tPlate Thicknessmm, inFieldYesxxx
caCorrosion Allowancemm, inFieldYesxxx
EJoint Efficiency<none>FieldYesxxx

4.3.3. Ellipsoidal Head

4.3.4. Flat Head

4.3.5. Hemispherical Head

4.3.6. Torispherical Head

Torispherical Head Dimensions
Fig. 4.3.6.2. - Torispherical Head Dimensions
Dimensions Tab, Torispherical Head
Fig. 4.3.6.1. - Dimensions Tab, Torispherical Head
Variable
Name
Unit
Type
Required
Description
<none>Type<none>SelectYesxxx
DInside Diametermm, inFieldYesxxx
LInside Crown Radiusmm, inFieldYesxxx
rInside Knuckle Radiusmm, inFieldYesxxx
sStraight Flange Lengthmm, inFieldYesxxx
tPlate Thicknessmm, inFieldYesxxx
caCorrosion Allowancemm, inFieldYesxxx
EJoint Efficiency<none>FieldYesxxx

4.4. Material

module-tab
Fig. 2.1. - Drawing
Variable
Name
Unit
Type
Required
Description
<none>Is the Material Normalized?<none>CheckboxNoxxx
<none>Use your own values?<none>CheckboxNoxxx
<none>Material Name<none>SelectYesxxx
SuTensile Strength at Design TemperatureMPa, psiFieldYesxxx
SyYield Strength at Design TemperatureMPa, psiFieldYesxxx
EmdElastic Modulus at Design TemperatureGPa, kpsiFieldYesxxx
SAllowable Stress at Design TemperatureMPa, psiFieldYesxxx
SaAllowable Stress at Ambient TemperatureMPa, psiFieldYesxxx
mdMaterial Densitykg/m^3, lbf/in^3FieldYesxxx
<none>Group Number<none>FieldYesxxx
<none>P-Number<none>FieldYesxxx
<none>P-Number Thicknessmm, inFieldYesxxx
<none>External Pressure Chart<none>FieldYesxxx
<none>UCS-66 Curve<none>FieldYesxxx

4.5. Settings

module-tab
Fig. 2.1. - Drawing
Variable
Name
Unit
Type
Required
Description
mdmtMinimum Design Metal Temperature°C, °FFieldYesIt's the the lowest temperature at which the material can safely withstand the applied stresses without experiencing brittle fracture. For now, the User must define the MDMT by it's own using the latest version of ASME BPVC Section VIII Division 1 (see UG-20(b)) but we're planing to create a tool to aid the User to define it.
<none>What Test specification should be used?<none>CheckboxNoUser can choose between 3 types of test that the Part will be subjected: Hydrostatic Test according to UG-99(b), Hydrostatic Test according to UG-99(c) and Pneumatic Test according to UG-100. For now User must check latest version of ASME BPVC Section VIII Division 1 for the description about each test. We'll later create a Documentation dedicated to this topic.
<none>Disable sharing of this Part?<none>CheckboxNoIf checked, other Users will not be able to add this Part to their Equipment. Part owner can still add it to his own Equipment.
<none>Include Operating Hydrostatic Pressure?<none>CheckboxNoIf checked, the hydrostatic pressure (caused by fluid column) will be taken in account in the calculations (will be added to operating pressure)
<none>Include Test Hydrostatic Pressure?<none>CheckboxNoIf checked, the hydrostatic pressure (caused by test fluid column) will be taken in account in the calculations (will be added to test pressure)

5. Messages

The Module will show messages in the results pages when needed.

5.1. Warnings

5.2. Info

6. Sharing

User that owns the Module can share it with other User by accessing module data in the Project Management page. A complete guide can be found in its Documentation .

Currently there are two types of sharing status:

  1. Full Access this type of access let the User make changes to the Module but can't delete it.
  2. View Access User with this type of access can't make changes, can only see the results page.

7. Limitations

The version 1.0.0 comes with some limitations which are listed below:

  • This version can't be used to calculate the following situations:
    1. Shell under External Pressure (UG-28);
    2. Stiffening Rings (UG-29);
    3. Head with Pressure on Convex Side (UG-33);
    4. Spherical Shell (UG-27(d));
    5. Negative temperatures.

8. Equations

The equations shown in the Results page come mainly from ASME BPVC Section VIII as this Module focus in such standard code. The only equations that didn't come from the Code is the volume and weight, which we used some math and trigonometry to find out.

List of equations that we didn't find in the Code and is used in the Module:

9. Results

9.1. Quick Table

The Quick Table (see Fig. 9.1.1.) shows the most important information from the results. It also shows if there's some error in the calculation (it'll be shown in red).

In the future version we'll let the User select which information want to see in it.

module-tab
Fig. 9.1.1. - Quick Table

9.2. Input

The Input tab (see Fig. 9.2.1.) in the results page shows all the information from the input page. It can be used to check all the data inserted by the User and by our system. The input will also be shown in the Calculation Report (DOCX).

module-tab
Fig. 9.2.1. - Input List

9.3. Output

module-tab
Fig. 9.3.1. - Output List

10. Testing

If you access the Shell & Head Design module without being logged, you'll see a warning message as shown in the Fig. 10.1. stating that you're entering into a testing environment, which basically means that you'll not be able to use it in a real case, as some features are disabled and the data range that can be use is limited.

testing-environment-001
Fig. 10.1. - Testing Environment Warning

If you need to use the it beyond its testing limitation, contact us through Contact page and we'll see what can we do for you. We could, for example, give you a 1 day free trial or a guided testing with us.

10.1. Limitations

There are two types of limitation in the Testing Environment: features disabled and data range restriction.

10.1.1. Features Disabled

Feature
Limitation
System of UnitsFor now (version 1.0.0) the System of Units is disabled for every case, not only for testing environment. We're still checking the real need to make Imperial Units available.
FluidOnly the fluid ASTM — Ref Motor Fuel C (50% Aromatic) are available for testing. Before you ask, we choose it at random. As the fluid isn't required by the calculation, we believe that disabling its selection won't affect the User experience.
TypeTwo types are available for testing: Cylindrical Shell and Torispherical Head. We've choose it because it's the most used types.
Material NameOnly the material SA-512 A are available for testing now but we're evaluating the possibility to let the User choose between 3 materials, to test the Search Material feature.
What Test specification should be used?Only the Hydrostatic Test (UG-99(b)) is available for testing. As it's quite simple calculation, it shouldn't affect the User experience while testing the Module.
Disable sharing of this Part?Sharing didn't affect the calculation and isn't shown in the Calculation Report, so disabling it should't affect User experience.
Include Operating Hydrostatic Pressure?Hydrostatic pressure can sometimes be neglected in the calculations because it's usually very small, so disabling it shouldn't affect User experience. If you want to calculate it by yourself, just check this article Hydrostatic Pressure on Head and Shell.
Include Test Hydrostatic Pressure?Same as the option Include Operating Hydrostatic Pressure? but in this case we're using he test pressure, which are higher than the operating pressure but, even so, it's value continues to be very small.

10.1.2. Data Range Restriction

Variable
Description
Limitation
<none>Decimal Places1 to 3
ToOperating Internal Temperature0 to 120°C
PoOperating Internal Pressure0.5 to 2.0 MPa
TdDesign Internal Temperature0 to 120°C
PdDesign Internal Pressure0.5 to 2.0 MPa
ToeOperating External Temperature0 to 120°C
PoeOperating External Pressure0.5 to 2.0 MPa
TdeDesign External Temperature0 to 120°C
PdeDesign External Pressure0.5 to 2.0 MPa
<none>TypeCylindrical Shell or Torispherical Head
DInside Diameter1 to 600 mm
slShell Length1 to 1200 mm
tPlate Thickness1 to 12 mm
caCorrosion Allowance0 to 5 mm
EJoint Efficiency0.45 to 1.00
LInside Crown Radius1 to 600 mm
rInside Knuckle Radius1 to 150 mm
sStraight Flange Length0 to 30 mm
mdmtMinimum Design Metal Temperature0 to 60°C

10.2. Access Protection

The public API used in the testing environment is different from the API used in the production environment. So, even if someone tries to direct access the API with values outside the data range, the API will return an error.

References