Last Changes dPIPE 5.27

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: