## Piping Calculators

#### Calculations are per ASME B31.1 Power Piping, B31.3 Process Piping, B31.4 Pipeline Transportation Systems for Liquids and Slurries, B31.5 Refrigeration Piping, B31.8 Gas Transmission and Distribution Piping Systems, and Miscellaneous.

**Descriptions / Examples**

Examples below show only small portions of the main files. The PipingOffice calculators are compatible with Microsoft Excel 2007 and later.

You will not need much prior Excel experience. These tools are user-friendly and may improve your understanding of the ASME Piping Codes.

**Piping Calculators Main Menu:**

A Menu file allows the user to choose and open each calculator by title and subject.

**Pipe Required Thicknesses per ASME B31.3 Process Piping:**

This example is per ASME B31.3 Process Piping Code. All materials are retrievable from a separate data file. Dimensional data are retrieved by clicking dropdowns. All common ASME standard NPS and DN pipe sizes and thicknesses are included.

Flange ratings are chosen per B16.5 for design pressure input. The flange ratings can be overridden.

Similar files for calculating required thicknesses are included per ASME B31.1, ASME B31.4, ASME B31.5, and ASME B31.8. (examples not shown).

**Pipe Allowable Pressures per ASME B31.1:**

This example is per ASME B31.1 Power Piping Code. All materials are retrievable from a separate data file. Dimensional data are retrieved from a shared data file. All common ASME standard NPS and DN sizes and thicknesses are included.

Threaded pipe is included. So is tubing. Pipe dimensions are chosen for either US Customary or Metric units.

Flange ratings per ASME B16.5 are chosen and displayed for reference.

The user must review and possibly edit input for joint efficiency, thickness allowance, and mill tolerance. Piping Code notes and longitudinal weld joint efficiencies can be viewed.

Printing of the whole area of allowable pressures will fill about 6 pages.

If you make the mill tolerance zero (0), and the thickness allowances zero (0), the calculations will be for pipe of actual measured thickness or pipe that is ordered as minimum wall.

You can determine the allowable pressure of corroded pipe.

Similar files are included per ASME B31.3, ASME B31.4, ASME B31.5, and ASME B31.8. (examples not shown).

Hydrostatic and pneumatic testing calculations were added in the January 26, 2019 update of the B31.3 allowable pressures file.

**Pipe Branch Reinforcement per ASME B31.1:**Designs are for unreinforced, ring, pad, saddle, or full encirclement.

This is a huge time saver.

Data included for all materials and numerous dimensions. ASME B16.5 flange ratings are selected for reference. Pipe dimensions and pressures are chosen for either Imperial (US Customary) or Metric units.

Two very different layouts are used in PipingOffice. The most useful is the one with calculations for one branch at a time. It allows calculations for a second branch placed next to the first and overlapping reinforcment zones can be included in the calculation of required reinforcement.

The other method allows calculations for 190 possible
combinations of header to branch size. Dimensional data
are retrieved by macros from a shared data file.

This calculator determines if reinforcement is required or
not, and if header or branch thickness is adequate. Also,
if a calculation is valid for the diameter-to-thickness
ratio or size ratio.

Results in are displayed in a box
similar to a branch table in a piping line class
specification (most large companies use branch tables in
their specs).

There are many choices of branch types that a designer
can use per the Piping Code. __(See PDF file of Full
Encirclement graphics per ASME B31.4.)__

Branch reinforcement designs to ASME B31.3, ASME B31.4, ASME B31.5, and ASME B31.8 are done in similar files (examples not shown).

**Extruded Outlet Branch Reinforcement Design per ASME B31.4:**

(1st part)

(2nd part)

This spreadsheet gives the ability to design two branches on the same header and reinforcing zones could overlap.

Inputs include selections by dropdowns. You can override the standard dimensions. Features are similar to those of the other calculators above, but with 2 branches side by side.

Similar extruded outlet branch reinforcement designs per B31.3 and B31.8 are also provided.

**Mitered Elbow Design per ASME B31.3 Process Piping Code :**

All materials are retrievable from a separate data file. Pipe dimensions and pressures are chosen for either Imperial or Metric units. Dimensions are chosen from a table using dropdowns.

Results include allowable pressures for both multiple miter and single miter elbows. Comments, ASME B31.3 notes, and joint efficiencies are referenced and weld joint values are placed by macros.

Mitered elbow designs to ASME B31.1 are done in a similar file (example not shown).

**Pipe Bend Design per ASME B31.3 Process Piping:**

All materials are retrievable from a separate data file. Dimensions and pressures are chosen for either Imperial or Metric units. Dimensions are chosen from a table.

Results include allowable pressures and required thicknesses. Comments, ASME B31.3 notes, and joint efficiencies are referenced, and weld joint values are placed by macros.

Pipe bend designs to ASME B31.1 are done in a similar file (example not shown).

**Steam Safety Valve Installations per ASME B31.1**(Calculates discharge reactions, pressure and velocities in discharge and vent piping, SIFs, predicted stresses in branch, anchor reactions).

ASME B31.1, Power Piping, Appendix II presents the designer with guidelines and alternative design methods applying to rules for safety valve installations.

The "Safety Valve" worksheet should be used primarily to determine reactions due to discharge of steam safety valves. The results can be entered in pipe stress analysis programs. Refer to ASME B31.1 Appendix II for complete application of the rules, including open discharge systems, closed discharge systems, installations with single and double outlet valves, multiple valve installations, etc.

The calculations presented in this spreadsheet are for an open discharge system with one safety valve.

Safety Valve Installations per ASME B31.1, Appendix II Para. II-7 Sample Problem

- Determine pressure and velocity at discharge elbow exit.
- Calculate maximum operating pressure for discharge exit.
- Calculate reaction force at discharge elbow exit.
- Calculate bending moments at branch Points (1) and (2) from reaction force and seismic motion.
- Calculate stress intensification factors at branch Points (1) and (2).
- Calculate predicted stresses at branch Points (1) and (2), and compare with allowable stress.
- Calculate maximum operating pressure for vent pipe.
- Check for blowback.
- Calculate forces and moments on vent pipe anchor.

The file contains dropdown boxes for selecting material, condition of steam, and sizes of inlet, discharge, and vent pipes. The user can choose either degrees-F or degrees-C. Interpolations are made for intermediate table values for Young's modulus and allowable stress. Fanno line graphs and a dynamic load factor graph are provided.

**Support Span, Shoe Bearing, and Weight Data:**

It calculates pipe and tubing support spacing (or span), support shoe bearing and weights. Results include weights of pipe, tube, fluid, insulation, plastic liner, refractory, ice on exterior, cross-sectional areas, and more.

Simple support spacing, continuous support span, cantilever, and shoe bearing calculation results are shown with graphics that help explain their meanings. Concentrated loads can be entered at mid-span to consider valve or other added weight.

Insulation density is converted to lbs/in^3 for convenience of Caesar II input. This file includes tables that allow selections via dropdown boxes for materials, material densities, dimensions, insulation, and plastic or refractory liners.

The user should change the data tables to indicate the brand or brands being used.

**ASME B31.3 Chapter IX, Allowable Hi-Pressure Pipe or Tubes:**

This is typically for pressures above the ratings for ASME B16.5 Class 2500 flanges.

Thickness reduction allowances can be entered for inside or outside, or both. Threaded pipe and tubing are included. Dimensions and pressures are chosen from tables with either Imperial or Metric units.

Data tables are included for materials in Section K of the Code. Printing of the whole area of allowable pressures will fill about 2 pages.

If you make the mill tolerance zero and thickness allowances zero, the calculations will be for pipe or tube of actual measured thickness or that is ordered as minimum wall. You can also calculate the allowable pressure of corroded pipe or tube.

**Theoretical External Collapse Pressure:**

(Method 1) (PDF) (Method 2) (PDF)

This file calculates external pressures which could produce plastic buckling and elastic collapse.

This is not per ASME Code except for external pressure not exceeding 15 psig.

When elastic collapse occurs due to external pressure, the pipe reshapes into lobes. The minimum number of lobes is 2. In a collapse with 2 lobes, the pipe cross-section will resemble an hourglass or figure-8.

**Stress Intensification and Flexibility Factors:**

(B31.1 fab. tee example)

(B31.3 ell example)

Calculations are for factors for pipe fittings. The results are used in pipe stress analysis. SIFs per ASME B31.5 are done in a similar file. Some formulas are slightly different in each Piping Code.

**Line Blanks (Line Blinds), Spacers, Spectacle Blinds (Figure-8's), and Restricting Orifices Design per ASME B31.3:**here

Allowable Pressures and Spec Sheets. This file calculates design thicknesses, dimensions, and weights of line blanks, spacers, spectacle blanks (figure-8's), and restriction orifices per ASME B31.3 -2016, para. 304.5, Eq. (15). Data from ASME B16.48, ASME B16.5 -2003, and ASME B16.47-1999 are also applied. Raised face and ring joint designs are included.

**Linear Interpolations in a Table Without Using Macros:**

This shows an example of creating a dropdown box control for material selection and a slider control box for temperature change. Formulas contain the Vlookup function for retrieval of stress values of selected material. Linear interpolation is then done to determine a stress value at any temperature over a range of data. Macros are not used.

Ben A. Nottingham

USA

Email:

*PipingOffice*