The Programs for Strength Calculation in Pipelines

10 th International Symposium„Topical Problems in the Field of Electrical and Power Engineering“Pärnu, Estonia, January 10-15, 2011The Programs for Strength Calculation in PipelinesJelena Priss, Ivan KlevtsovTallinn University of Technologylenapriss@hot.ee, Klevtsov@staff.ttu.eeAbstractThe trend of development Estonian oil industry,related to European Union strict technologicalrequirements, needs developing methods ofpipeline optimization on the basis on strengthcondition analysis. This paper presents an overviewand comparative analysis of 4 strength calculationprograms (START, RAMPA, LV pipe II, CAESARII). The following factors were used for analysis:computational algorithms and basic standards,technical specs, application areas, graphicsfunction, error checker and reports. There arementioned the risks of the usage of manualstrength calculation.KeywordsPipeline construction, strength calculations,standards, programs, manual calculation.IntroductionThis paper draws on ongoing PhD thesis “Pipingoptimization on the basis of strength conditionanalysis”. The paper is structured as follows. Afteran overview of the theoretical issues the paper willprovide an overview of the programs analysis forpipeline construction.The paper considers the description of four differentprograms (START, RAMPA, LV pipe II, CAESARII) for strength calculation. The programs areanalyzed by standard, program developer, technicalspecs, language, application areas, graphics function,error checker and reports.to choose the configuration of pipeline and, at thesame time, to avoid unnecessary pipelinecomplication. It is necessary to arrange the supportstaken into consideration so that they do not reducepipeline compensating capacity. Strength calculationallows finding correct solution for supportsplacements, their types and characteristics.Programs characteristic and comparisonRequirements to technical calculation of programThe main requirements to technical calculation ofthe program are considered in this part of paper. Theprogram is supposed to calculate:• Reactions, forces and moments in supports andconnected equipment• Pipeline forces and moments• Displacements• Strength and stress calculations according tostandard EVS-EN 13480• Nozzle loads• Wind loads• Friction• FatigueThe main characteristics of strength calculationprograms are given in Table 1.Table 2 shows feature comparison of programsRAMPA, START, LV pipe II and CAESAR II.STARTPipeline constructionPipeline is basically a transport structure. Productsfor transport: liquid, gaseous, toxic and explosive.Technological areas are sewerage plants and watermanagement facilities, power engineering, chemicaland petrochemical industry, nuclear powerengineering.Strength calculations are necessary in the design ofpipelines. Strength calculation gives an opportunityFigure.1. START user interface209

Table 1 .Strength calculation programs characteristicsProgram RAMPA START LV pipe II CAESAR IIStandardDeveloperRussian FederationStandardISTC „Dipriz“Russian FederationRussian FederationStandardNTP„Truboprovod“Russian FederationEVS-EN 13480“LauterbachVerfahrenstechnik”GermanyInternational ISO„COADE“USALanguage Russian Russian German, English EnglishProducts fortransportTechnicalspecsApplicationareasGraphicsfunctionError checkerand reportsSteam, hot water,oil, gasMicrosoft Windows2000 / DOS (DiskOperating System)PipelineconstructionSteam, hot water,oil, gasMicrosoft WindowsXPPipelineconstructionSteam, hot water,oil, gasMicrosoft Windows2000 / XP / Vistaand as Excel 2000Thermal processengineering,pressure vesseldesign and pipelineconstructionSteam, hot water,oil, gasMicrosoftWindows XP/Windows VistaProcess and plantdesign, pipelineconstruction3D 3D 3D 3DIntegrated Integrated Integrated IntegratedTable 2. Requirements to technical calculation of programProgram RAMPA START LV pipe II CAESAR IISupport reactions x x x xForces and moments x x x xElbow ovality x - - -Displacements x x x xEVS-EN 13480 - - x xNozzle loads x x x xWind loads x x x xFriction x x x xFatigue x x x xSpring hangerspropertiesx x x xSTART is the most widely used pipe stress analysisprogram in Russia and CIS countries. START iswidely used by major plants and design companiesin chemical, oil and gas, power, metallurgy andother industries. The START program is fullycertified according to Russian standards.Strength and rigidity analysis for steam and hotwater pipelines, main gas and oil pipelines, processsteel pipings. Branched 3D pipelines with variousdesign of end and intermediate supports, withvarious expansion joints made in the form ofcorrugated, lens-shaped, stuffing box, or bellowstype pipe compensators under static and cyclicloading of various nature (temperature expansion,concentrated and distributed loads, supportmovement, tension, and compression) are calculated.If required, the program automatically selects springsupports and calculates their tightening torque.Pipeline and fixtures strength and bearing capacityassessment is done for various Russian standards(conformity with norms confirmed by Certificate ofGosstroy RF ROSS RU.SP11. N 00003 Gosstroy RF№ 0075985).210

CAESAR IIFig. 2. CAESAR II user interfaceCAESAR II makes it easy to input and display allthe data needed to accurately define a piping systemanalysis model. Input can be accessed or modifiedon an element-by-element basis, or datasets can beselected to make global changes. The CAESAR IIinput graphics module makes quick work ofdeveloping analysis models while clearly indicatingareas of concern and providing an excellent idea ofthe piping system's flexibility. Colour-coded stressmodels and animated displacements for any stressload case are available. Besides the evaluation of apiping system’s response to thermal, weight andpressure loads, CAESAR II analysis the effects ofwind, support settlement, seismic loads and waveloads.The CAESAR II program includes an integratederror checker. Reports are clear, accurate conciseand fully user definable.CAESAR II incorporates table look-ups for pipingmaterials and components plus expansion joints,structural steel sections, spring hangers and materialproperties including allowable stress. This ensurescorrect datasets are used for each analysis. CAESARII is certified according international piping codes.Features:• Static and dynamic analysis• Intuitive analysis model creation• Cutting-edge graphics• Load and view plant model• Comprehensive error checking• User-definable reports• Wind and wave analysis• Seismic and support settlement analysis• International piping codes• Extensive material databases• Steel databases and modellingLV PIPE IIThe LV PIPE II user interface is completelyintegrated into MS EXCEL. The EXCELenvironment enables the user to implement his owndata and links and to create the documentationaccording his preferences. Results of a calculationare totally separated from the input (EXCEL sheets).Fig. 3. LV PIPE II user interfaceFeatures:• Maximum number of allowable displacementcycles is documented• The displacement of the pipe system can bepresented animated for every load case• The node numbers are presented perspectively(same size) to grant the utmost clarity inpresentation. Numbers and names are scaleableand rotatable.• Pipes marked in the Excel sheet are highlightedin the graphics simultaneously• CAD-Options: Export of graphics as 2D or 3D-DXF for further use (Stresses presented incolours)RAMPARAMPA carries out verifying calculation of strengthin which, besides the internal pressure, it takes intoaccount the action on the pipeline of additionaloperational loads from the following factors:• Weight of the metal, the transported fluid, heatinsulationand the fittings of pipeline system• Thermal expansions (self-compensation) of thepipeline• Thermal expansions and other deformations instructures of the attached equipment andsupporting system• Possible residual curvature of the pipeline as aresult of accumulation of plastic creepdeformations, so-called “self-extensions”At verifying calculation of durability of the pipelinethe program defines equivalent stresses for all itstesting sections and typical details (arc and sectorelbows, tees), compares to allowed stress and comesto the conclusion of performing of standardconditions. Besides strength estimation the programcalculates design loads on the equipment andsupporting constructions at verifying calculation ofpipeline system where the special stage ofcalculation is carried out for spring suspension(assembly, simplifying system adjustment).The maximum equivalent stresses in pipelinesections are defined on the basis of main stresscomponents with application of the theory of the211

greatest tangential pressure (the third theory ofstrength or the theory of H. Treska)The RAMPA program is fully certified according toRussian standards.Manual calculationDurability and resistance of pipeline depends ondifferent external factors: thermal expansion,concentrated and distributed loads, displacements ofthe supports, stretching. These factors are caused byrandom temperature fluctuation of transportedproduct. There is a risk for the pipeline system tomake strength calculation manually. For theestimation of the pipeline stability it is necessary tomake calculation with program.StandardAll strength calculations should be done accordingto standard EVS-EN 13480.ConclusionThe paper presents a comparative analysis ofprograms applicable for design of pipelinesoperating under different temperature, internalpressure and external mechanical loads.Present analysis helps to consider programsavailability on the energy market.Strength calculation programs analysis is necessaryfor the future researches in this field.The next steps for ongoing PhD thesis are:• Test the demo version of programs• Analysis of pipeline strength calculationsReferences1. http://www.kpria.cz/en/pevnostni-vypocty-adynamic/types-of-strength-calculations/(23.11.2010)2. http://www.coade.com/products/caesarii(24.11.2010)3. http://www.truboprovod.ru/en/about/it.shtml(24.11.2010)4. http://www.lvsoft.com/software/fachbereiche/rohrleitung/index.htm (26.11.21010)5. http://www.ckti.ru/rampa.html(26.11.2010)212