Pipemill: a suite of piping design & analysis programs

 

·         Complements pipe stress analysis packages with a suite of programs for common ancillary needs in piping design, analysis, and layout.

·         Takes the grind out of the complex (or the simple but repetitive) calculations often needed for the design and layout of piping systems.

·         Written by an experienced piping stress engineer, Pipemill has been used on numerous projects.

·         Benefits accuracy, design quality, and delivery schedules.

Facilitates common piping design tasks e.g.…

·         pipe flange design and analysis (three methods)

·         clamp connector design

·         expansion loop displacements, loads and stresses

·         PSV and Rupture Disc force calculation

·         prediction of acoustic fatigue

·         external pressure/vacuum design

·         jacketed pipe analysis

·         pipe span chart creation; sloping line calculation

·         pipe support heat transfer.

Other key features of the software:

·         totally portable. Runs from a USB memory stick

·         several databases of pipe data and piping component data

·         context sensitive help designed to answer most queries

·         comprehensive hard copy output

·         user guide (by an experienced piping stress engineer)

·         validation calculations available for all routines.

Try out Pipemill for yourself: download an evaluation copy from the Downloads page. Or buy or order Pipemill (an lvySoft piping Engineering software product)

Support: Send an e-mail to pipemill@pipemill.com with a description of the problem (or your needs).

 

 

1. New version

·         Selective Main Menu

·         Acoustic fatigue risk assessment (EI method)

·         Flow induced vibration analysis (EI method)

·         Fluid hammer force calculation

·         Pipeline surge risk analysis

·         Pipe and support indentation evaluation

·         Limit state analysis of offshore risers.

 

2. Main menu in Pipemill

3. Pipe flang design/analysis (&ASME VIII Div 2)

3.1 ASME VIII & PD 5500

Standard or user-defined flange designs

To initiate a new flange analysis, either a standard or user defined design must be selected.

·         If a standard flange is required, data bases of ASME B16.5, ASME B16.47A & B and API 6A or 6B dimensions may be accessed.

·         A user design may be of any valid dimensional set. On screen graphics aid the selection of final proportions.

Types of flange and gasket analysed

·         Flange types considered include weld-neck, slip-on and flat plate types.

·         The flange face may be raised face, ring type joint (RTJ) or full face.

Design factors allowed for

Loads applied may include pressure, external bending moments and external forces.

Analysis output

Analytical results and graphics (see right, graphical shape factors) are presented along with further available design options.

Calculated and allowable stresses are shown together with primary system loads and associated data (bottom right).

Other intermediate data may be viewed, along with the flange and bolt weights, based on actual metal mass.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Extensive help files: explanatory comments on many of the key inputs; gasket characteristics and data; bolting

·         Scientific calculator

 

3.2 EN1591 & EN13445

The pipe flange design method to EN codes (i.e. strain-based) represents a new approach to flange analysis and design. This Pipemill program is included to provide an alternative and potentially superior method to the traditional one found in ASME VIII / PD 5500.

Types of flange and gasket analysed

Currently, integral pipe flanges of all types with flat or ring type joint gaskets may be analysed.

Design factors allowed for

Pressure, external bending and axial forces at the flange are all taken into account in the program (detail, right, of ring joint dimensions used as part of the input data).

The strain-based analysis also allows for elasticity of the entire flange, bolt and gasket assembly.

Prevention of flange leakage is a paramount criterion.

Flange analysis output

Screen and printed results are limited to pertinent data, helpful scale plots and component weights. Angular deflection of flange faces under load, and resulting edge clearance, are presented.

Comments on the strain-based analysis method

The strain-based analysis method is mathematically complex. It is not feasible to present on screen or hard copy all the intermediate steps leading to the final results.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Extensive help files: explanatory comments on many of the key inputs; gasket characteristics and data; bolting

·         Expansion and materials data

·         Scientific calculator

 

4. Pipe clamp connector design

Hub and clamp or ‘Grayloc’ type pipe connectors may be designed and analysed in accordance with ASME VIII Div. 1 Appendix 24.

Design input

Input is similar to the pipe flange design program, with:

·         input data panels (see right, top & below) specific to the pipe connector hub, clamps, bolting, and gasket. Bolt spacing may be varied within allowable limits.

·         internal pipe pressure, connector bending moment, and pipe axial force inputs

Connector analyses output

·         Full code comparison stress results are presented.

·         A scale section plot, views of the clamp, and additional calculated data may be viewed (as right, below). The scale plots enable the design to be visualised and a better finished product obtained.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Extensive help files: explanatory notes and comments on many of the key inputs; comments on different calculation methods, where appropriate; gasket characteristics and data, from ASME VIII; bolt areas, by size

·         Scientific calculator

 

5. PSV/rupture disc forces

Force calculations for the initial or ‘pop’ condition and under sustained flow may be carried out for gas and vapour PSV’s (pressure safety valves) discharging into a closed header, or directly to atmosphere.

Rupture disc forces for gas or vapours can also be calculated.

Design input

·         Fluid characteristics (pressure, molecular weight, etc.)

·         Pipe dimensions

Analyses output

·         Reaction forces (kick forces) present in a liquid relief valve and a rupture disc may be calculated, for the initial and sustained conditions.

·         A warning and alternatives are provided (marked in red, right, bottom) due to the following: as gas flow approaches and exceeds sonic (Mach) velocity, the API equations will tend to predict higher PSV reaction forces than would exist if flow were limited to Mach speed.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Explanatory notes and comments on API 520

·         Scientific calculator

 

6. Acoustic fatigue prediction

Acoustic fatigue prediction using Energy Institute method Method

The EI method is based on work done by the Marine Technology Directorate in a study of vibration induced fatigue in process pipework generally, and particularly in duplex steels.

The method allows up to three streams form noise sources and combining at a header to be fully analysed. A further stream with defined noise properties may be added, which may be the output of a previous small network calculation, and allows a much larger network of piping, branches and components to be accurately assessed. The behaviour of Duplex Stainless steel is specifically addressed.

Results

Results for each defined location and branch connection type in the network are clearly displayed with clear indication of acceptability or otherwise.

Alternative method

The simpler and well known Carruci and Meuller approach to recognising the risk of acoustic fatigue in piping is also available in Pipemill. The method is accepted as ‘rough and ready’ and may be significantly in error.

 

7. Vacuum/external pressure design

Pipes, tanks and vessels may be evaluated for their resistance to collapse under external pressure and/or vacuum. With Pipemill, ring stiffeners may then be designed to prevent collapse (as right).

Evaluation is in accordance with ASME VIII Div. 1. [IUG-28, UG-29 not mentioned yet]

Pipe stiffening design

The pipe or cylinder may be un-stiffened or have stiffener rings of user designed, or standard, sections (see right, below (stiffener component data)).

Materials data included

Common materials data may be accessed from the integrated Pipemill database, which includes digitised curves.

Note: Certain paragraphs of the ASME design code allow use of nominal wall thickness where clearly the actual minimum should be considered. Pipemill always uses the minimum wall thickness.

Analysis support

·         Example analyses

·         Explanatory notes

·         Scientific calculator

 

8. Rotating equipment nozzle loads (incl. EN 5199)

Nozzle loads applied by piping to various types of pump and compressor, and to steam turbines, may be analysed with Pipemill.

Codes covered

·         API 610 (10th Ed.) Centrifugal Pumps, API 611 Refinery Steam Turbines, API 617 Centrifugal Gas Compressors, API 610 Input Data

·         NEMA SM-23 Steam Turbines

Two axis systems are available

Two axis systems are available, one using the API local axis system (Z upward) and one utilising the more common global axis system used in piping stress analysis (Y upward).

API 610 Output Data

Output is presented with respect to the various clauses in the code. Each calculated load combination is presented with its respective allowable value, and acceptability or failure is highlighted.

NEMA SM-23 Input description

Up to four nozzles may be analysed (right, top). Shaft axis may be horizontal ‘X’ or ’Z’. The resolution point may be defined by the user.

Code specific results are produced. If overloaded, a diagnostic panel will be presented identifying the source of the problem.

Analysis support

·         Example analyses

·         Explanatory notes: General; and on aspects of API 610, NEMA, API 611, and API 617 affecting the analyses

·         Scientific calculator

 

9. Pipe support stress analysis

Trunnion type pipe supports and vertical riser (stack) type supports may be analysed using Pipemill.

Both calculation routines include the effects of external loads and internal pressure.

Trunnion supports

·         Trunnions may be with, or without, a stiffener ring and attached to straight pipe, or attached to an elbow (duck foot type). (Example output, top right)

·         The method used is based on Kellogg ‘Design of Piping Systems’, with both local and global stresses reported.

Riser supports

·         Riser supports may include or exclude horizontal stiffener rings. (Example output, bottom right)

·         Analysis is based on Blodgett's ‘Design of Welded Structures’.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Scientific calculator

 

10. Jacketed (insulated) pipe analysis

The aim of this element of Pipemill is:

·         to provide all the data required to carry out a formal stress analysis of jacketed pipe commonly used for sulphur and bitumen transport, steam or other hot fluid flows; and for insulated pipe for cryogenic service, or similar.

·         to provide post stress analysis results not otherwise available.

Calculation of key pipe data

A compound weight and stiffness of jacket, core pipe, pipe contents and insulation may be calculated for an initial stress analysis without the need for complex modelling of the entire jacket and core.

Jacket pipe axial and closure loads/stresses

·         Axial stresses are calculated and, for compressive stresses, the risk of buckling of either jacket or core may be predicted.

·         Local stresses in a typical closure end plate may be calculated.

Analyses support

·         Example analyses

·         Explanatory notes and comments on each set of calculations

·         Scientific calculator

 

11. Pipe tee design: ring reinforced and stub-in types

       Pipemill enables the design of reinforced and stub-in tees manufactured from plate or straight pipe. Code compliance is with ASME B31.3 Section 304.3 (2004), or BS EN 13480.

Input variables of note

·         Lateral branch connections are allowed to an angle from the perpendicular of 45 degrees.

·         Ring or saddle reinforced tee may be specified

·         Standard pipe sizes from integrated database

Pipemill results

·         Results are presented in full and summary form

·         Iterative optimisation is facilitated by a results summary overlaid on the input screen

·         Stress intensification factors are calculated for all connections.

Errors and warnings

Pipemill will flag if the tee needs ring reinforcement.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Explanatory notes

·         Scientific calculator

 

12. Pipe/elbow wall thickness calculator

Pipemill can calculate, in accordance with ASME B31.1, B31.3, B31.4 and B31.8 codes:

·         minimum wall thicknesses for:
- single element pipes
- curved elbows.

·         a range of pipe sizes, in one run for B31.1 and B31.3, so allowing the rapid preparation of a piping specification document.

The nearest commercially available pipe sizes are output, using an integral database.

Calculations to ASME B31.3 include Chapter IX, high pressure design and fatigue analysis.

Input data

·         pressure, temperature, allowable stress, corrosion allowance, mill tolerances, weld joint factors, etc.

·         optionally, a range of pipe sizes from 0.5 in. nb (nominal bore) up to 80 in. diameter for evaluation in accordance with ASME B31.1 and B31.3 in English or Metric units

·         curved elbow details, as an alternative to straight pipe.

Calculated pipe sizes

·         minimum required wall thickness, or the minimum corroded wall thickness

·         when applicable, a range of suitable pipe sizes (diameter and wall thickness per size), which can be printed as a single printout.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Explanatory notes on ASME B31.1, B31.3, , B31.4, and, B31.8

·         Scientific calculator.

 

13. Design of large bore, refinery-type fittings

This part of the Pipemill program is intended for the design of large bore refinery type fittings where standard components may not be available:

·         line blinds

·         end caps

·         mitre elbows, with any number of cuts

Calculations are in accordance with ASME VIII B31.3 (line blinds, mitre elbows) and ASME VIII Div. 1 (2000) (end caps).

Input data

Pressure, temperature, allowable stress, corrosion allowance, mill tolerances, bend radius, etc.

Special features

Stress intensification factors are calculated for mitre elbows.

Analysis support

·         Example analyses

·         Integral database of commonly available pipe sizes, with automatic input of selected pipe data

·         Scientific calculator

 

14. Slug forces; vessel skirt/ pipe expansion

This part of the Pipemill piping design suite of programs is intended to deal with those simpler calculations, which might be unreliable if written down from memory. It is intended that the input screen is largely self explanatory.

Calculations programmed include:

·         Vessel skirt expansion

·         Dynamic forces at a pipe elbow due to liquid slugs in a gas stream

·         Linear interpolation of values

·         Thermal expansion rates for common pipe materials

·         Axial elongation of straight pipe due to internal pressure

·         Alternative methods of assessing external loads on flanged pipe joints.

 

15. Pipe/ fittings/ value data

Several databases of pipe and piping date are coded into Pipemill:

·         Commercially available pipe sizes to ANSI B36.10, B36.19 and API 5L dimensions

·         Flange dimensions to ANSI B16.5, ANSI B17.47A & B and API 6A

·         Valve dimensions to ASME B36.10

·         Material data curves for external pressure design

·         Expansion characteristics of various materials to ASME B31.3

·         Gasket data for EN1591 / EN13445 flange application

The databases, above, are accessed by the various programs. Some can also be accessed from the main Pipemill menu, bottom right panel (middle image, right), and are covered in more detail on this page.

Pipemill's pipe data (weight, section modulus…)

This program allows the user to click on a standard size pipe, or enter user defined data. The software then calculates:

·         weight, moment of inertia, section modulus, pipe wall area and internal flow area for the given size. Weights calculated include pipe, contents, insulation and cladding material.

·         An equivalent density and thickness representing insulation and cladding is provided for input to the many piping stress programs that allow only one value for ‘insulation’.

·         Stress intensification factors (SIF's) for standard fittings may be calculated.

Dimensions for standard pipe flanges, fittings, and other components

In this program, clicking onto an equal size fitting alone will provide:

·         individual and compound dimensions for that pipe size to ASME B16.

·         Flange overall dimensions from ASME B16.5, B16.47A and B and API may also be viewed.

If the user clicks on the same pipe size and flange size, fit-up dimensions will be provided for:

·         flanges and fittings

·         reducing fittings.

Valve dimensions to ASME B16.10

A complete data base of all ASME B16.10 valve dimensions is included, such as:

·         gate valves, plug, ball, and butterfly valves

·         swing check valves, wafer check, angle check, lift check, and Y-type check valves

·         angle globe, standard globe, & Y-type globe valves.

The user needs only to click on a pipe size and valve type, to obtain in-line dimensional data for raised face (RF) and ring type joint (RTJ) constructions.

If a particular type or size is not available this will be flagged.

Further pipe data sources

The data in Pipemill is intended to cover the great majority of needs. However, if more comprehensive piping information is required, try Zeataline PipeData-PRO.

 

16. Expansion loops

·         Four typical expansion loop types are available.

·         Data bases for standard pipe size and wall thickness and expansion characteristics may be accessed, or user data entered.

·         Displacements, stresses and end loads are calculated.

·         Allowable stress is calculated in accordance with ASME B31.3 and any over-stress will be clearly flagged. The calculation is based on a stiffness matrix and results compare well with commercial stress analysis packages.

·         Iterative runs may be performed to optimise loop size.

Analyses support

·         Example analyses

·         Explanatory notes and comments on each set of calculations

 

17. Span charts/ slope design

A span chart may be created for standard pipe sizes or user entered data.

In addition to the usual limits of deflection and stress limitation, the basis of calculation (end conditions) may be selected.

Up to 20 pipe sizes may be run in one calculation.

Results are routed direct to the printer.

·         Example print output: Allowable pipe spans (1 page, 28Kb)

Sloping pipe design

Sloping lines must be designed to prevent pooling of liquid by proper definition of the slope with respect to span and deflection.

Pipemill allows calculation of a free draining sloping line based on either the required slope for a given span, or the maximum allowed span for a given slope. As above, end conditions may be selected.

Analysis support

·         Example help screen shown right.

·         Example analyses

·         Explanatory notes and comments on each set of calculations

 

 

18. Pipe support heat transfer

The program applies principles outlined in ASTM C 680-04 to estimate heat transfer from a pipe support shoe, enabling an assessment of local temperature at the base plate.

Heat transfer methods considered

·         conduction, and

·         convection.

Types of pipe support covered

The pipe support may be:

·         a simple tee type

·         a double axial plate, or including a web stiffener.

Outputs

Temperature gradient against shoe height is produced in two forms:

·         numerical

·         graphical.

Analysis support

The help file contains typical thermodynamic data for common pipe support materials.