• 1. An option "drug and drop" for the insertion of "extra data" into the nodes of the calculation model is implemented (https://youtu.be/3C0cXwD8EyU)
  • 2. Fixed procedure for automatic meshing of the model when inserting a tee joint in the node: a new node merges with the previous one if the distance between them is less than the minimum length of the element (see the EL_LEN parameter in the CTRL command)
  • 3. The functionality for the insertion of a new node and breaking a branch with the help of Graph Input tools is added for rigid element. Editing of the rigid element may be done by double mouse click with CTRL key
  • 4. For a "straight pipe" and rigid link elements, information about the element is added to the quick edit dialog. This dialog is called by double-clicking the left mouse button for a straight pipe, or by double-clicking the left mouse button with CTRL for a rigid element

  • 5. Fixed error resetting the load group parameters when editing elements
  • 6. The change of directions after BEND/MITER elements is blocked for the next element
  • 7. The situation when the thickness of the branch appeared less than the thickness of the matched pipe was changed from an error to the warning
  • 8. Display of the support under the valve's body is fixed
  • 9. Fixed program crash when copying and pasting a piping section with a FLEX element
  • 10. Display of seismic groups of supports is fixed
  • 11. A scaling of additional data when displaying the analysis model in one line is blocked
  • 12. Fixed program crash when inserting a force into the node


New Analysis Options:

1. Provisions of new Code is implemented in the program: non-mandatory Appendix A "Alternative method for stress analysis of piping" from GOST R 59115.15-2021 “Justification of Strength of Equipment and Pipelines of Nuclear Power Plants. Calculation of strength of typical pipeline units”. Generally, this document repeats requirements and approaches of the PNAE, but has some differences. Accordingly, the following changes have been introduced into the program:

  1. equations for allowable stresses are harmonized with new strength criteria installed by GOST R 59115.9-2021 “Justification of Strength of Equipment and Pipelines of Nuclear Power Plants. Calculation of strength”;
  2. fatigue curves used in analysis are calculated based on temperature-dependent specific material properties. See Appendix XVII of the help file for details;
  3. the requirement to fulfill the shakedown criterion (SRK stress) is now mandatory;
  4. coefficients used for calculation of temperature stresses due to gross structural discontinuity or material discontinuity are revised

The following options under the CTRL command set analysis according this CODE:

CODE = 'PNAE', CODE_YEAR = 2022:

Additional parameters required for calculation of fatigue curves are added in the Material Properties: material type and reduction of area Z:

These new data are already added in the “mat.dbs” file. Apart of that, for the environmental fatigue analysis an additional field “KO” is added in the “Operational modes” input window. KO stands for water oxidation in milligram per kilogram and is defined with help of new ENVFAT command. The column with KO becomes available for editing providing the option “Concentration of dissolved oxygen” in the fatigue analysis specification is activated.

2. Accelerations of the valve’s body and actuator are printed in results (*.sup file) individually for each dynamic load case, (watch video ).

3. Realization of High Energy Line Break (HELB) procedure for PNAE Code is upgraded. Added adaptation of this procedure for EN 13480, see Appendix XVIII of the help file.

4. The data for spring hangers design from Hesterberg catalogue is added in the sh.dbs file

User Interface Changes:

5. Elements of graphical input of the piping model are added in User Interface:

  1. Drawing of straight pipes, (watch video )
  2. Insertion of Bends/Elbows along branch, (watch video )
  3. Insertion of intermediate nodes, (watch video )
  4. Split the branch to insert support with option CNODE, (watch video )

6. The functionality of measuring angles between piping sections has been added to the program interface

7. The weight of the selected piping segment may be calculated with new command, (watch video ).

8. An incorrect assignment of a seismic category to piping elements generated by automatic FE meshing has been fixed (applicable for PNAE analysis)

9. The numerical value of MCOM option for modal combination is visible now in the dialogue window:

10. An option “Edit table on double click” is added in the “Display options” tab. Its activation allows to avoid the "beep" system signal when one double-clicks on the fields in the "Additional data", "Section" and "Group" columns of the "Geometry" table."

11. Displaying of the damper located on the vertical piping run in 3d view is fixed: it is shifted relative to the axis of the pipe

12. Files with databases (*.dbs) are localized: depending on used interface language they are located in folders en-US and ru-RU respectively

Fixed bugs:

1. An incorrect assignment of a seismic category to piping elements generated by automatic FE meshing has been fixed

2. Fixed a bug that caused the program to crash when copying a section containing an angle valve with different sections

3. The command “Files/Make Archive” has been fixed for files containing dot in the file name

4. The output of maximal accelerations of the valve’s body and actuator has been fixed for the case of several dynamic load cases: the maximum values along all sets of excitations are printed out.

5. The requirement to define R2 parameter for branch connections is no more mandatory: in case of its omitting corresponding SIFs are defined as twice greater. See note 9 to ASME NCD-3673.2(b)-2

6. The additional checks for TR and TB parameters of the standard tees are added: TR < DR/2 and TB < DB/2

7. The function of saving changes while editing data in DDE pivot tables of piping supports is restored

8. The following error has been detected and fixed: the values of the corrosion allowances for bends and reducers were taken from the last preceding straight pipe element (this problem is relevant for use of EN-2020 Code.

9. Printout of friction force for restraints defined in the global coordinate system has been fixed

10. The option for simplified fatigue procedure (FATG_SAF='YES') is no more acceptable for High Energy Lines Break (HELB) calculations. This limitation is relevant for PNAE Code analyses.

11. Calculation of thermal stresses due to gross structural or material discontinuity has been fixed (applicable for PNAE or ASME NB analyses)

12. Dimension of moments in the database with allowable loads on supports (sup_lds.dbs file) for the TITAN-2 catalog (TITAN-2_R1_7) is fixed

13. Functionality for viewing animation of the dynamic piping motion in PIPE3DV is restored

14. PIPE3DV: viewing of the one-component restraint located on the vertical piping run and defined in the local coordinate system has been fixed

15. PIPE3DV: a number of decimal digits may be increased in the results tables with new option added in settings, (watch video ).

16. PIPE3DV: option for the gradient coloring is added for viewing piping deflections, (watch video )

17. PIPE3DV: accelerations printout is added in the window activated by “Node info…” command. Spreadsheet view is also available (CTRL-R), (watch video ).

18. PIPE3DV: defects of the displaying stresses in half-opaque elements and rendering of bends in the "wire" model mode are fixed.

19. PIPE3DV: the view of cumulative usage factor distributed along pipe is fixed (the color scale has been adjusted):

dPIPE Utilities


loss of accuracy during exporting time-history data in the external file (*.dat) has been fixed: more digits added in the column with time values

dPIPE 5.27

There was discovered an error in the dPIPE 5.27, Build from November 15, that led to an inaccurate calculation of stresses in the “standard” tee elements analyzed according to the Russian PNAE or RD (boiler) Codes. The error may appear if the values of tolerances (parameters CR & CB) for these elements were not defined explicitly. The new setup with correction (from November 18) is available on the site.

dPIPE 5.27

1. The printout of the allowable loads for supports from the "OTT_0157-2013" catalogue has been corrected

2. The error of reading data from the CUSTOM table (database file “sup_lds.mdb” with the permissible loads on supports) has been fixed

3. The input of data for the modeling of Cross Tee has been fixed

4. Manipulation with comments rows is fixed for the Layout spreadsheet

5. The check of the minimum wall thickness in comparison with the wall thickness of the reference section has been corrected for the BEND element (the strict inequality has been changed for a non-strict one: SMIN ≤ S ref. section)

6. The recording of the file with TEE element’s stress time histories (TH_OUT parameter): has been fixed: originally, if there was no output of other time dependencies, the file was not written or an error was issued

7. The output of the valve’s accelerations required by the OTT check has been corrected: in the case when several dynamic design cases exist, the accelerations of the valve were displayed for the last DLC only. Now the maximum values among all DLCs defined in the analysis are printed out

8. The "optimization" operation for merging of different branches of the computational model has been improved: now it’s available for selected piping segments

9. The assessment of the accumulated fatigue damage using the FATG command is blocked for the analysis of high-temperature piping according to the PNAE Code (CODE = ‘PNAE_T’). The exception has been left for calculations with the “Simplified calculation” option (FATG_SAF = ‘YES’)

10. The option "Delete unused data" available under the command "Tools/Optimize model" has been improved

11. Assessment of the calculated vs permissible loads for spring hangers was corrected for the TEST and TEST_B analyses types: if the springs are locked in these regimes there is no need to check a permissible load for springs

12. The option to choose beam’s section has been added for the "FROM" command In the LAYOUT spreadsheet

13. The check of the maximal number of records in the file "vlv_ott.dbs" (a database with OTT allowable loads for valve nozzles) has been introduced. The maximum allowed number of records has been increased to 5957.

14. The rule "RVRS" has been added for stresses from occasional loads, which defines that dynamic seismic loads are reversible. This rule applies to calculations performed according to ASME Code (edition after 2010) or EN (edition 2020).

15. The option to read the CTRL command from the "solv.dbs" file is added. In this case, the explicitly described parameters from the database replace the existing ones and add the missing parameters to the CTRL command in the *.dp5 file

16. The crash of the program has been fixed occurred when entering the weld coefficient in the "Piping Sections" table

17. The printing of warnings (“!” sign) in overloaded valves displayed in PIPE3DV by the command “Element parameters” is fixed

18. The record of the database with pipe cross-sections (file pipe.dbs) is fixed: RD norms, standard "OST 108.320.102-78": link to the reference section for the pipe stamped elbow ‘CS530x65’ changed from ‘CS490x90E’ to ‘CS570x95

19. The record for S_III stresses (RD Code, file “SOLV.DBS”) for the joint calculation of high and low-temperature piping has been corrected

20. Option for the assessment of stresses due to seismic anchor movement separated from the seismic inertial loads has been added for Codes ASMS NB/NCD, edition 2010 and later: in the POST command for stresses RES = 'EQ9_C', RES = 'EQ9_D', the rule 'SAM' is introduced

21. Printout of maximal stresses for the BEND elements according to ASME NB Equitation (12) is recovered for the table with fatigue analysis results (section “SUMMARY TABLES WITH RESULTS OF ANALYSIS”, file *.res)

22. Fixed the work of the "Advanced" tab of the "Operational modes" table (data entry for calculating stresses from the temperature gradient). Applicable for PNAE and ASME NB Codes

23. Input of comments in the table with restraints has been fixed: before it led to the abnormal termination of the program.

24. The calculation of the postulated rupture locations of high-energy piping is realized for analyses undertaken according to the 'EN' norms

25. Changes according to edition 2020 of the EN 13480 "Metallic Industrial Piping" Code are implemented in the dPIPE

26. The option for selection of the criteria document between ANSI/ANS 58.2 and SRP Section BTP 3-4, NUREG-0800 is added for the HELB analysis, see parameter DOC at POST_HELB command

27. A summary table with the location of postulated ruptures (breaks and cracks) is added in file *.sup (HELB analysis).


1. The command "Mutual multiplication of spectra" has been renamed to "Modify spectrum" with the ability to multiply / divide the selected spectrum by the reference curve

2. The option "apply only to selected records" is implemented for the command "Replace in names"

3. The procedure for calculating the response spectra has been modified: the refinements affected the high-frequency range and high damping values

4. The functionality for calculation of response spectra from accelerograms when setting frequency-dependent damping in accordance with RG 1.61 has been added


1. The display of the rotated local axes of the beams is fixed.

2. The display of the node labels, miters bends and rigid struts transferred from the dPIPE model to the DXF file is fixed

3. The coloring of support's seismic groups for elements adjacent to piping supports is corrected

4. The algorithm for drawing the local coordinate system of piping segment located at an angle to the horizontal plane is fixed

dPIPE 5.27

1. The error occurred during dynamic analyses when the calculated spring load exceeded the maximum value has been fixed.

2. Calculation of stresses EQ11, SGM4, SGM5, where the input parameter has referred on stresses calculated with the "MAX" rule (EQ11, SGM4, SGM5) has been fixed

3. All tables with input data are redesigned. The column with comments is added to every table

4. Fixed the error that occurred when assessing the valve’s nozzle loads according to NP-068 in the frame of dynamic analysis with an option “Small Bore Pipes”

5. An unnecessary run of the modal analysis has been fixed (this situation happened when the modal LC was set before other static LCs)

6. Key's shortcut CTRL-F4 is set for the close of the current window

7. The procedure of stresses S2 calculation in the frame of dynamic analysis with small bore pipes option is corrected

8. The functionality for the input of the element 3-way Valve is restored

9. The output of “PARAMETERS FOR DYNAMIC ANALYSIS” has been specified (File *.out, Listing of Input Data). Now these parameters correspond to the data set in the first dynamic load case (DLC)

10. The output of stress intensification factors for models containing both 1st and 2nd safety class pipes has been fixed.

11. Calculation of section modulus ZB & ZR for “standard” tees have been corrected for fatigue analysis in the frame of ASME NB Code

12. The output of SRK and KE values (they appear in the printout if SAF > [SAF]) has been fixed for analysis with Small Bore Pipes option

13. The warning message instead of error will appear in case if the insulation will be detected on the internal pipe (jacketed pipes)

14. Additional check if the height of the branch is defined will be done for standard tees having different from the matched pipe outside diameter and wall thickness

15. the parameters for the SIF calculations are specified in the input dialogue windows of the WELD and REDUCER elements

16. The parameters for the SIF calculations have been clarified in the input dialogue windows of the WELD and REDUCER element (applicable for ASME B31.1 and EN codes)

17. The setting of FATIGUE analysis is disabled for all norms except ASME NB and PNAE (the FATG command)

18. Functionality of the calculator is inserted in the fields for the coordinates of the node (node properties, POS command)

19. Unintentional conversion of relative paths to the database to absolute has been fixed (command DBF)

20. The context menu item "Delete rows" of the "Geometry" table has been moved above, under the item "insert row". Added confirmation when deleting a row

21. The proper work for the export of piping sections from the table with the same name to the external file has been restored

22. Corrections have been made for the set of dynamic analyses (THA) with and without the seismic anchor movements

23. More strict check of the material properties dependent on lifetime is introduced (applicable for RD and EN codes)

24. A context menu for inserting/deleting rows is added to the Table “Analysis Specification”

25. A check if the declared response spectra contain data is added

26. Tables «LISEGA2010RSENR2» and «TITAN-2_R1_7» were added in the file SUP_LDS.MDB containing allowable loads for piping supports. These tables contain data from the following Manufacturer’s catalogues:

 “Catalogue of the standard elements for piping supports for ISO 4200:1991 pipes”, Revision 1.7, JSC “TITAN-2 holding”;

 “Standard Supports 2010 RS EN. Addendum to LISEGA catalogue “Standard Supports 2010" in reference to Russian standard pipe dimensions for nuclear application, Rev. 2” by LISEGA

The structure of the file SUP_LDS.MDB and the command SUP_LOADS have been changed to allow the following features: now it is possible to set the rated permissible load and tables with correction factors applied depending on the seismic category of the pipe and the operating temperature. A detailed description is given in Appendix XII of the User Manual (help file)

27. The following spring tables from the TITAN-2 catalog were added in the file with characteristics of the springs (SH.DBS): ‘T2’ – springs with working range 50, 100, and 200 mm and load capacity up to 100 kN; ‘T2_XL’ – springs with working range 50, 100, and 200 mm and load capacity from 53 up to 400 kN; ‘T2_RU’ – springs with working range 70 and 140 mm and load capacity up to 58.5 kN;

28. It was detected that directions of STX and STY restraints and components of supports displacements were incorrectly determined after operation “Rotation of the model around Z-axis”. This error has been fixed

29. An option for the selection of the spring of the determined type has been realized. In this case, spring id should be defined in *.dp5 file as id = ‘0/0/25’ (25 is spring type from the corresponding spring table)

30. File MAT.DBS with materials data: for steels with the designation $12X1MF and $15X1M1F* (code RD), an explicit indication of the lifetime of 100 thousand hours has been added. Before that, when using these materials, the lifetime was assumed to be 200 thousand hours by default

31. The printing of stresses in the PIPE element that models the standard tee branch from the RUN axis up to the RUN surface is suppressed if the ratio between mean radiuses of the BRANCH and RUN is less than 0.5

32. An optional show of the stresses in the external “transparent” pipe is realized:

33. The valve’s nozzle loads assessment results could be seen in PIPE3DV through the "information for the element". If results are negative elements are blinking and a red exclamation sign appears in the right top corner of the window. The blinking can be switched on/off with the use of the ALT-SHFT-E shortcut.

watch video



34. Similarly results of the piping supports load capacity assessment could be seen in PIPE3DV through the information for the node. Supports with unacceptable results are blinking If the criteria are not satisfied, then a red exclamation sign appears in the right top corner of the window. The blinking can be switched on/off with the use of the ALT-E shortcut.

35. The export of the calculational model geometry from PIPE3DV to the DXF file has been fixed: elements "rigid struts" have been added, the display of miters and names of nodes of the model has been fixed

36. PIPE3DV: for guides and sliding supports, their type (STG/STG-, STZ/STZ-) and the value of the friction coefficient used in the calculation have been added to the "node information". For spring supports - the friction coefficient is shown.


1. An operation to set contrasting colors of the shown records is added (CTRL-W).

watch video



2. An operation to multiply spectra by the reference line is added,

watch video



3. An functionality for transferring records from the "Folder" to the root of the project tree is added

watch video



dPIPE 5.27

1. A new command “Reset workspace” has been added to the “Tools” menu item, allowing to reset the program’s interface to the default settings (windows layout, keys shortcuts, etc.)

2. The command for search in the text and in the graphic window has been modified: the option for search with the use of wild cards has been implemented; the functionality of the command has been expanded and its interface simplified. The search is performed over the entire text of the * .dp5 file with automatic positioning of the found fragment to the window focus.

3. Processing of the parameter ANGLE of the REDUCER command representing a tapered part of the element has been fixed. Changes are relevant to ASME and EN Norms

4. Processing of the MITER element has been changed: a check of the ratio between the radius, the number of cuts, and the full angle of the element have been added. Also converting data from old formats is fixed

5. The size and position of the fields of the "valve with offset" dialog have been changed: on some laptops the dialog did not fit the entire screen and the buttons were inaccessible

6. The check of the node name length of the field "support under the body" in the element "valve with offset" has been added

7. An optional key “NOPOS” has been added to the DPC module (compiler of input data). It allows to ignore predefined coordinates of the nodes (POS command) and identify separate branches not connected with the main line of the model. In some cases, existing of separate branches may lead to the error "non-positive definite matrix". Command syntax (run from command line): dpc.exe .dp5 /NOPOS

8. The field for ID is added to the WELD command. ID will appear in the input/output listing and in PIPE3DV as well

9. A summary table for the transient nodal load is added to the program interface: Additional Data/Dynamic Loads

10. An additional check is added for the "standard” tee: the setting of the component’s weight is allowed if the size of the tee is given (run length and/or branch height are defined)

11. An option for an accounting of the concentrated forces among other loads is restored for the type of Load Case “OPER_R”

12. The program's hangup is fixed occurred sometimes during working via remote access due to loss of Internet connection

13. Text search with wildcards is implemented. Searches in the text and graphics windows have been modified and corresponding icons added

watch video



14. Corrections of primary stress indexes B2 have been introduced for components with Do/T ratio > 50. This change is relevant for codes ASME_NC/NB 2010.


1. Changes have been made to the program interface (menu items and their names have been reorganized), see the help file

2. The work with the system of units has been updated: it is assumed that all records in the project (spectra and time histories for accelerations, velocities, and displacements) are stored in mm/sec2, mm / sec, and mm, respectively. The same units are used to export data to external files or to the clipboard. To display graphs in other units, the program provides a corresponding interface (see menu item “Plot tools/Units System”).

3. Developing of the median spectra has been updated. The number of standard deviations may be defined by the user (+/- N*SIGMA)

watch video



4. An option for calculation of cut-of-frequency for the specific spectrum is added

watch video



5. A procedure for expanding the peaks of the response spectra by a given value to the right and left of the peak is added (this option may be useful in the frame of structural analysis with soil properties variation).

watch video



6. Automatic saving of * .SM files created during dPIPE session is canceled

7. Procedure for grid lines is improved

8. Buttons for creating and navigating between project pages are added to the toolbar

9. Axes scaling algorithm is improved

10. Navigation along the project tree is improved (the cursor position is remembered when switching between pages)

watch video




1. The functionality for editing a line's style by double-clicking on a chart line or from the context menu is added

1. Fixing of the small bugs in the module for transferring data from dPIPE to LICAD RS

2. The orientation of the one-directional supports (restraints) resulting after rotation of the model around axis Z is fixed

3. Processing of the relative links in *.dp5 file during project archiving is fixed (command file-make archive)

4. Fixing of the small bugs in the module for transferring data from dPIPE to LICAD RS

5. Postprocessor bug is fixed caused the failure of the problem when in the frame of one-run several different dynamic methods were utilized (RSM & THA).

6. Fixed a bug led to the program's failure if there were specified several dynamic analyses using different sets of accelerograms.

7. The bug in the procedure that involves seismic anchor movement in case of several sets of seismic inputs is fixed

8. Fixed a bug led to the program's crash occurred when calculating SGM4 stresses (CODE = ‘EN’) for load combination included a range of seismic anchor movements

9. DDE has started to show strings-comments from the dp5 file and keeps them after the model has been changed. Comments for “extra data” (any text following after semicolon) are stored as well. The corresponding interface has been added to the program interface

10. The command DP2LCD (export of the supports loads to LICAD software) may be exported from solv.dbs file along with specifications for “standard” analysis and postprocessor.

11. The “Optimize” operation can now be applied to the selected part of the model (see the "Change" mouse context menu available after selection).

12. An additional parameter “ref_node” is added to the extra data syntax. It’s available for those extra data that has direction and located in the node where more than two elements are connected

13. The interface for the element "miter elbow" is changed (see Help file)

14. The order of input arguments in the command POST is restricted when rule “SEISM” or “S_SRSS” is used”: for FRCS, SUPP, DISP types of results if the first argument is LS, then rest of arguments should be LS as well.

15. The content of the “Control parameters/Dynamic” tab has been modified: the parameters existing in the Analysis Specification (the “Dynamic calculations” tab) have been deleted.

16. The commands SUP_LOADS and DP2LCD can be read from solv.dbs file (specifications for the “standard” sets of analyses)

17. Calculation of Seismic Anchor Movements (SAM) has been fixed for the case when several Dynamic Load Cases were applied for the model

18. The parameter “Number of Flanges” is added for bends and miters (applicable for ASME/EN codes)

19. The procedure for fatigue evaluation considering seismic loads is fixed

20. An allowable range for the command GRAD parameters (discontinuity stresses due to temperature gradient and stratification) has been changed: the values can be either positive or negative. Similar changes were made to the STR_DISC command

21. “Liftoff” warning for supports under combination NOC + SSE (OBE) using the SEISM rule has been fixed.

22. Correction of the dampers seismic displacements by the accounting of the global Seismic Anchor Movements (SAM). This change concerns calculations when Time History Analysis was utilized and SAM was introduced through the corresponding groups of spectra.


1. Changing the model coloring algorithm by category (colors have become more "contrasting")

2. Custom setting for the font used in the form “Element/Node Info” is added

3. Number of cuts at miters corresponds to the used number in the input data


1. An algorithm of the spectra’s peaks smoothing and broadening has been improved

1. Processing of the links containing relative paths (SPEC, ACCE, DBF, DFRC commands) is added. The option is applicable when * .dp5 file is saving to another folder.

2. Processing for files with time history records (TH_OUT command) is added for the case of several time history analyses in the frame of one calculation.

3. Input and processing of the dynamic forces set are fixed. Applicable for the time history analysis.

4. Specific material may be assigned for the VALV element

5. The procedure for the location of postulated ruptures of High Energy Lines within ASME Class 1 piping HELB analysis is modified

6. The RULE = ‘RANGE’ is added for evaluation of stresses calculated by equations (12) and (13) for ASME NB-3600 Class 1 piping analysis

7. The limitation for the names of fatigue curves used for Austenitic Stainless Steels for ASME NB-3600 Class 1 piping analysis is exempted

8. Processing of the parameter HELB_STR (prefix used in the name of piping classified as High Energy line) is fixed

9. Calculation of Sm value for Equation 12 (ASME NB-3600, code year 2010) is changed: now Sm is the an average of the tabulated Sm values for the highest and the lowest temperatures of the metal during the transient

10. The interface between the results of dPIPE calculations and the LICAD program is implemented for the LISEGA supports. See details in the help file.

11. The option for archiving the source data files and calculation results is added. This functionality is useful for archiving projects and data exchange. This feature requires .Net Framework version 4.5 or later.

12. In the "External programs" dialog, the processing of the "Arguments" line is added with the "Request Filename" option enabled.

13. The output of Fv value (demand to capacity ratio) in the table “Assessment of valve's nozzle loads according to NP-068-05” has corrected. The bug appeared in version 5.27.

14. Executable modules are digitally signed by the Vendor.


1. The check of the presence of zeros in the response spectra record is added. The program reports warning when such records are found. Simultaneously the operation for deleting zeros was added (menu item Edit, Adjust Spectra with Zeros)

2. The spectra records are checked for the repetitive frequencies. If such frequencies are detected correction with several options is proposed.

3. Settings for the legend’s and axes fonts are added (Menu File/Settings)

4. The functionality for the synthesis of accelerograms from the set of spectra with different damping is added.

1. A bug in the module for the printout of the input data is fixed: the program crashed if in a set for dynamic calculations a comment was specified.

2. DCASE command: an option for use of the damping parameter and seismic motion duration is added. Applicable for some types of modal combinations: CQC/DSC in the frame of Response Spectrum Method.

3. Fixed a bug in the postprocessor module, resulting in the crash of the program, when the dynamic analysis run after spring design not satisfying criteria for the spring load variation

4. Incorrect work of postprocessor module has fixed. The error occurred when LOAD CASE with TYPE = ‘MODAL’ was set in the last place. The bug has appeared in the Release 5.27 of February 12, 2019

5. Fixed a bug in the postprocessor module, resulting in the crash of the program when time history analysis has been used for small bore pipes.

6. PIPE3DV: Appearance/disappearance of piping supports in the model is fixed when the model is reloaded within the same session

1. Fixed incorrect work of the program with models containing CS elements (cold spring)

2. Processing of the stresses of categories S1 / S2 (PNAE norms) with reference to the dynamic loads set is fixed

3. Navigation and editing of the comment fields in the "Analysis specification" tab is fixed

4. The proper work of the program in demo mode has been restored. The program had been failing if the dongle was not found

5. The processing of the element “Valve with offset, VO” is fixed: the bug has appeared in the Release 5.27 of February 12, 2019

6. The processing of the dynamic force in the frame of dynamic time history analysis has fixed

7. The problem with number of modal analyses more than two is fixed

Analysis options:

1. Engineering approach for seismic analysis of small bore pipes is implemented (see Appendix XV in the help file):

2. Option for the solution of several dynamic load cases in the frame of one model is added:

The commands SPEC, ACCE and DFORC were modified in this regard:

The commands SPEC, ACCE and DFORC were modified in this regard:

The tab with “Dynamic Analyses” has been added to the SOLV & POST specification window.

Reference on the dynamic load cases should be made in the postprocessor commands:

3. Element REDUCER got the reference on the specific material

4. Added option for assessment of loads acted on rigid struts with use of support's database (sup_lds.mdb file)

5. The rule for selection of Operational Mode compatible with the calculation of seismic stresses is changed: now it is taken from the reference of the first member in the load case combination used as a reference for seismic stresses. The previous approach used operational mode defined for the modal load case. This change may be useful for load combination Abnormal Conditions + Seismic Load.

6. Printing of the summary table with fatigue analyses (cumulative usage factors) results has restored. This problem has appeared in the last release of the program for models without predefined names for piping segments...

7. The processing of the “standard” tees has been fixed for the seismic anchor movement analyses in the frame of dynamic time history calculations

8. Calculation of the allowable stresses used for SGM4 stress category (EN-13480 Code, 2012 ) is corrected (stresses has become higher)

9. An indication of the point where the loads on the valve’s nozzles have exceeded the allowable values according to OTT assessment is added in the printout:

10. Calculation of the allowable stresses used for SGM2 stress category (EN-13480 Code, Sub-Clause 12.3.3) has updated considering allowable stresses for the occasional loads (parameter SOL in the MAT command)

11. Spring hanger’s database (sh.dbs) with characteristics of springs is upgraded with data from the catalogs of the following vendors: WITZENMAN, UNISON and GRADOUIR

12. The flexibility and stress intensification factors are corrected for the miter bends (this change is applicable for ASME and EN Codes)

13. Processing of the old TEE command is fixed for EN code.

DDE Spreadsheet

1. Coordinate axes and Legend may be moved along the screen with the use of (SHIFT + arrows) and (CTRL-SHIFT arrows) shortcuts correspondingly (this feature is realized by analogy with PIPE3DV)

2. In the "Help" menu item added "Tutorial"

3. 3D view of the force acting along the pipe axis is improved

4. Element for Angular Valve is modified:

1) "halves" of the angular valve can be of different lengths

2) Valve’s Nozzles may have different references on the OTT database items

5. Modeling of 3Way Valve is added in the User Interface.

6. A check of the radius of the bend or miter bend is added: error message will appear if R <= D/2

7. Editing functionality of the table with material properties is restored

8. The values for T-SR-TAU and T-SOL has been moved on a separate tab (applicable for the CODE = ‘EN’)

9. The size of arrays for the ultimate and yield stresses (SU&SY) may differ in the material table.

10. The current piping section may be assigned for FLEX element (it affects only 3D view)

11. An additional check is added for the prevention of assigning any of “External” data for the internal nodes of the valves (except for supports).

12. A conventional TEE has been removed from the DDE interface. For compatibility, the TEE command is still available in the source data file, but it is strongly recommended to use the "standard" TEE when creating calculation models:

13. For the data located at the branch points of the piping, which direction is determined relative to the pipe axis (forces, guides, restraints, snubbers), the additional check has been introduced. When using the “Additional data at the end of the file” option, a corresponding warning is issued:


1. Graphical presentation of stresses in the area of tee joints/branch connections has been improved.

2. Option for the thickness of the line to draw the "wire" model is added.

3. Captions may use different fonts and background color (applicable in the TEXT mode)

4. Fonts used for dimensions may be modified.

5. 3D View of Dynamic Forces is improved

6. Correct export of the model in DXF file is restored

7. Results in the Table may be shown partially depending on the visible parts of the model.

8. Option for automatic caption of the different piping categories (sections, materials, etc.) is added

dPIPE Utils


CVSpec + Sintez-M = CVSpec-TH:

New release of CVSpec software is issued. Starting from the current release, CVSpec has gained a new functionality: generation of the accelerograms from the response spectra. the program name has changed: CVSpec-TH. Please, be aware that we stop distribution of SINTEZ-M and will not conclude new contracts for its technical maintenance. All companies that have purchased the program and are under maintenance will be provided with the appropriate number of copies of the CVSpec-TH program, and our commitment to maintaining SINTEZ-M will be transferred to CVSpec-TH.





G-Frc: Calculation of the Jet Flow parameters and Fluid Flow Reaction Forces and resulting from the High Energy Pipe breaks




G-Frc is software for evaluation of the reaction forces exciting the high energy piping due to a release of the medium from a circumferential or longitudinal break. The program also allows assessing an impact of jet flow on the surrounding structures which are inside the zone of the jet expansion. Jet impact includes excessive pressure, temperature and wetness.

The results obtained by means of G-Frc could be used for the consequent piping dynamic analysis and also for the jet impact evaluation on the surrounding structures and estimation of their protection feasibility.

The code is based on the analytical model presented in American National Standard ANSI/ANS-58.2-1988 "Design Basis for Protection of Light Water Nuclear Power Plants Against the Effects of Postulated Pipe Rupture".

    According to ANSI/ANS-58.2-1988 G-Frc code considers for the following types of breaks:
  • Circumferential break with full separation (guillotine rupture);
  • Circumferential break with limited separation;
  • Longitudinal break;
  • Through-Wall Crack.
    For the case of circumferential break with limited separation two possible options exist:
  • pipe ends limited separation at the rupture is provided by the manner of the pipe fixing at the vicinity of the rupture;
  • pipe ends limited separation at the rupture is provided by the special flow limiter installation on the place of the pipe potential rupture intended for the medium flow rate reducing out of the rupture.
    The code can operate with the following mediums:
  • Saturated water steam;
  • Superheated water steam;
  • Pressurized water with the temperature less than saturation temperature but higher than 100oC;
  • Pressurized water with the temperature less than 100oC.

Two last-mentioned types differ by their ability to flash just at the rupture area.

    Jet impact on the target (civil structures, equipment, etc.) is evaluated under the following assumptions:
  • the target is located normally to the jet axis;
  • the target surface is significantly larger than the jet cross-section at the area of the jet impinging on the target, that is the jet impinging spot is totally disposed inside the target surface.

G-FRC can be used independently or being incorporated in dPIPE software.

Use of the program requires the protection key.

Demo version is limited only by one piping cross-section 620x25:

PIPE3DV: fixed a bug with visualization of concentrated forces.

1. Fixed a bug in the version of dPIPE 5.26: correction of the reduction coefficient of the circumferential weld strength. Applicable for stress calculations according to the Russian Boiler Code (Code = ‘RD’)

2. The parameters of standard tees are specified in database file “pipe.dbs”: changes are applicable for low-pressure carbon steel piping, CODE = 'PNAE', OST 34-42-XXX-84

PIPE3DV: fixed a bug with visualization of constant spring hangers

SINTEZ-M: Fixed a bug when program "falling asleep" during execution

Analysis capacities:

1. A postprocessing option has been added allowing to analyze High Energy Lines Breaks (HELB): stress-based calculation of the postulated rupture locations (command POST_HELB):

This analysis is available only under nuclear codes: PNAE or ASME NC/NB. Activation of this option requires special licensing.

2. A code-based strength analysis of NPP piping with a WWER type reactor has been realized in accordance with the Czech Codes «NTD A.S.I. Sekce III, Hodnocení pevnosti zařízení a potrubí jaderných elektráren typu VVER» (CODE=’NTD_ASI’):

Activation of this option requires special licensing.

3. Stress analysis (σ)1 has been added for analyses in compliance with PNAE:

Since PNAE Codes do not contain a formula to determine general reduced membrane stresses (σ)1 in various piping elements, dPIPE offers an engineering assessment of such stresses: calculations are performed only for elements “straight pipe”, “bend” and “pipe reducer” in accordance with the formulae applied to stress group (σ)2 taking into account only internal pressure and axial force.

Each entry for LS with a calculation specification for (σ)1 stresses shall immediately follow an analogous entry for (σ)2 stresses: allowable stresses for σ1 are determined depending on the previous set of results for σ2. For instance, for S1 and LS4 permissible values are assigned for a combination of a normal operating load + OBE, that is 1.2[σ]:

4. Command POST_REP now includes option ECOLD, which indicates cancellation of internal forces reduction to the “cold” (reference) elasticity modulus. When ECOLD = 'YES', the scaling of internal forces, which are used to determine stress ranges (amplitudes), to coefficient (Eref/Eh) is cancelled. The value of parameter E_MOD is hereby ignored. Parameter entry is available only in the text mode.

5. Command POST_REP now includes option SRK_RMT, which indicates accounting for tensile stress when calculating allowable SRK stresses in accordance with PNAE, p. 5.4.7 (is actualized when SRK_RMT = ‘YES’):

Parameter entry is available only in the text mode.

6. Procedure for fatigue analysis of tees has been adjusted in accordance with ASME NB-3600: summation of internal forces has been corrected taking into account reduction to the cold modulus.

7. Determination of stress intensification factors has been corrected for tees in equations (10) and (11) in analyses according to ASME NC-3600 (1992).

8. An error in stress calculation in a branch pipe connection has been corrected (Tee TYPE = ‘BRC’). The error (overrated stresses) appeared only in calculations complying to EN Code or ASME NC (2010) Code.

9. Calculation of nominal stresses for analyses complying to ASME NB-3600 has been adjusted.

10. Calculation of stress amplitudes in accordance with ASME NB-3600, equation (11), has been adjusted.

DDE Spreadsheet:

1. Indication of detecting a security key has been added to the interface:

In case the software has “lost” the security key, a double-click on the icon makes it search for the security key again. Button “Find security key” in dialogue window “About software” works in a similar way:

2. A message about the end of software maintenance when working with the later software versions has been added:

3. An option for auto-save of the input data file has been added:

4. Automatic restoring of input data in case of an abnormal end of a task has been added:

5. Item “Properties” has been added to the “File menu” allowing to access information on the input data file location. The path can be copied to the clipboard.

6. The case, when tee body elements belong to different load groups, has been reclassified from errors to warnings;

7. A drag and drop technology for transferring spectra/accelerograms from SINTEZ-M and CVSPEC utilities to dPIPE has been added.




8. A drag and drop technology for transferring input data files in the dPIPE format from explorer to DDE has been added.




9. It is now possible to export from a *.dp5 response spectra file into separate files with a consequent substitute of text to links:




10. Input and visual representation of static forces and moments have been altered (see Help):

11. Visual representation of tied and gimbal expansion joints has been altered: tie rods in accordance with the assigned angle BETA are displayed in the 3D mode. When drawn in line, expansion joint types are provided:

12. A summary spreadsheet for standard tees has been added:

13. Direct and reverse operations have been added in order to change the type of elements “straight pipe” <-> “rigid element”:




14. Option for inserting rows in the spreadsheet with analysis specification and result postprocessing has been added:




15. The dialogue window and spreadsheet for welds have been changed. New types of welds have been added (for analyses in accordance with ASME and EN):

BWELDGirth Butt Weld
SOCKSocket Weld

16. Printout of Kis, As coefficients has been added for standard tees:

Visualizing of calculation model analysis results (PIPE3DV)

New version of the Pipe3DV software has been released. The software code has been significantly reengineered: irrelevant options have been deleted, while the user interface has been improved:

1. Hotkey combination <CTRL-SHFT>-<TAB> has been added in order to switch between result viewing modes:




2. A language switch function has been added into the user’s interface:

When starting the programme, it is possible to regulate the interface language from the command line:

Russian interface:

 		Pipe3DV -l ru-RU <file name>

English interface:

 		Pipe3DV -l en-EN  <file name>

3. The “Apply” button has been added to the dialogue windows “Settings” and “Show notation”:

It is now possible to move “legends” across the screen using hotkey combination <CTRL-SHFT>+<arrows>:




4. Symbol for Tee has been added in the 3D mode:

5. Features have been added when displaying element local axes.




6. A reset option for default values has been added.

7. It is now possible to edit figure captions without accessing the respective dialogue.




dPIPE utilities:

SINTEZ-M: Minor interface errors have been corrected;


1. An option for reducing the number of points in the accelerogram has been added.




2. It is now possible to calculate time functions for displacements and velocities from accelerograms with a consequent application of a low-frequency filter.




3. An option to show ZPA (zero period acceleration) when displaying response spectra has been added.




4. It is now possible to save projects as XML files.

5. It is now possible to rename a group of files in the project entries (<CTRL>-<H>).




6. Dot-and-dash styles have been added to the line properties.

7. Project page templates have been added. Line properties, legend location, axis parameters can be kept in such templates. They can be either saved within the project or imported/exported through files.




8. It is now possible to drag objects in between two projects.




9. A function of creating an automatic report based on the project has been added (for further details, see Help).

Updates Software dPIPE 5.25

1. Functionality to keep current folder added for entering response spectra or accelerograms:

2. Pasting response spectra data from clipboard:




3. Interface for entering data depending on lifetime has been added (allowable stresses SA and creep-rupture strength SR, command MAT):

Starting from this release, window with materials data becomes read only. For editing/entering data use direct editing of text in *.dp5 file

Corresponding information for lifetime should be also entered in Operating Modes window (OPVAL command):

Described above options are applicable for the analyses performed according to the following Codes: «RD», «EN» and «PNAE_T».

4. The following error fixed: under pressing RESET button templates will be exposed by default corresponding to the selected interface language:

5. The error that caused the program failure during editing of extra data has been fixed

6. Functionality for the import of results for spring hangers has been recovered

7. The error that caused the program failure during selection of supports to assign seismic groups has been fixed.

8. The meaning of the «rigid» stiffness for the Expansion Joints is clarified over the program: interface, printouts and help file:

9. Loss of comments in the data for “standard” tees has been fixed.

10. Time dependent data for the allowable stresses have been added in the file mat.dbs (section for CODE = ‘RD’).

11. File "solv.dbs" has been complemented by specification for analysis of piping with low and high temperature parts (analysis according to Russian Boiler Code RD).

12. Option for preview of accelerograms has been added:

13. PIPE3DV has been equipped with option for export of compact GIF files with animation of free and forced vibration and piping deflections

«CVSpec» Program:

14. Bugs that occurred during "grouping" operations with spectra have been fixed

15. The Peak broadening operation has been added for the group of spectra

16. The options for the processing of time history records have been added (import, export, storing in Project file, preview, etc.):

«Sintez-M» Program:

17. Fixed various bugs related to the program interface.

1. Processing of the parameters for the “standard tee” element has been fixed: in the previous release instead of references to the attached pipes there were references to the pipe sections used for modeling of RUN and BRANCH pipes (tee reinforcing). This inaccuracy could affect the results of calculations according to the codes ASME and EN, if the standard tees were used in the models.

2. Additional data are introduced for the material properties: allowable stresses under the proof test conditions. Applicable for code EN 13480 "Metallic Industrial Piping":

3. Check of stresses due to sustained loads under Test conditions is added for code EN 13480 "Metallic Industrial Piping" (SGM1T):

4. Additional set of pre-defined specifications for analyses and post-processing is added to the file SOLV.DBS (calculations according to EN 13480 "Metallic Industrial Piping")

5. Check of model’s misalignments is added for the Flexible Joint element (FJ)

6. Additional functionality is added in the “Group operations with supports”: setting of uniform movements for all selected supports:

7. 3D representation of 6-component support is changer in PIPE3DV:

8. CVSpec can import group of spectra now:

Since this version the procedure of dPIPE licensing has changed: we move to Sentinel software for software protection. That requires updating of existing HASP keys.

New options for analyses:

1. The time required for calculation of eigenfrequencies and eigen modes has significantly reduced (DP5D module)
2. The limitation for number of various types of elements used for stiffness matrix assembling has removed
3. Procedure for consideration of welds in the region of tee/branch connections is specified
4. Parameter RD_E0330 is introduced for CTRL section (calculation of allowable stresses according to document RD EO “Lifetime Extension Guideline for the strength calculations of piping and equipment of RBMK, VVER and EGP reactor facilities”). Applicable for PNAE code only
5. Database for materials (file mat.dbs) has supplemented with fatigue curves from RD EO

6. Functionality of Seismic Anchor Movement (SAM) accounting has extended: options added to extract SAM response from total seismic demand (see in HELP: RULE = ‘SAM’, POST section).
7. Algorithm for calculation model optimization has improved.
8. Changes relevant to 2012 Edition has implemented in European Norms (EN 13480 "Metallic Industrial Piping").


1. Printout of Cumulated Usage Factor for standard tees in models with option SKIP_STR has fixed.
2. Calculation of SRK stresses when using LS reference has fixed
3. Minor bugs in results printout have fixed
4. Use of LS has added for SAF stresses (PNAE code)

DDE table:

1. Operations with standard tees have corrected (work with database, deleting of unused data, etc.)
2. Correspondence between parameters BEND_CODE, BEND_PRES and E_MOD entered in dp5 file and their representation in the “Options/Piping Code” dialogue has fixed
3. An option to save relative paths for files with data bases has implemented.
4. New menu item “Utilities” has introduced:

dPIPE Utilities:

1. Performance and stability of SINTEZ-M Software (generating of acceleration time histories) are significantly improved
2. Functionality of CVSPEC (Program for Response Spectra processing) has extended
3. Software for browsing viscous damper characteristics DmpView got new function for reporting
4. dPIPE Utilities (SINTEZ-M and CVSPEC) have been introduced in dPIPE interface

Visualization of the calculational model and results of analyses (PIPE3DV)

1. PIPE3DV has been equipped with functionality for showing and partial viewing of the calculation model according to piping outside diameter
2. Work with putting dimensions on the sketch has been improved