ROHR2 is used internationally and includes a large number of standards like ASME, EN, ISO14692, KTA, CODETI and RCCM.  ROHR2 automatically creates the load cases necessary to ensure that your analysis is code compliant.

ROHR2 has more and better standard interfaces than other stress programs we’ve seen.  Sigma is also able to create custom interfaces on an as-needed basis.

Yes, ROHR2 can read – and also write – Caesar II files in the *.cii neutral format.

Unlimited.  ROHR2’s architecture does not limit load cases or load case combinations.

ROHR2 includes an integrated tool (that can also be used as a stand-alone program) to dimension piping components or entire pipe classes.  This includes ASME evaluations of straight pipe, bends and elbows, tees and nozzles.

Yes and yes.  ROHR2 can evaluate nozzle loadings as per various codes (API, NEMA, etc) or to custom allowables.  A flange design tool is also included.

The material database that comes with ROHR2 is more comprehensive than any other we’ve seen.  This saves a lot of time without adding unwanted complexity since one can create a subset of the database for each user.  In this way, the selection set is not overwhelming and materials being used can be easily managed.

ROHR2’s views are customizable in every regard and can be stored for later recall, printing or automatic inclusion into reports.  Most users create stress isos showing node locations in this manner.  There is also an HPGL plot tool included where stress isos are generated automatically without overlapping information.  With the module ROHR2iso, users can also add dimensions and a bill of materials.

One of the features that distinguishes ROHR2 is the template-driven report generation capabilities.  Users can use templates provided with ROHR2 or create new ones where a report is generated in Rich Text Format.  As revisions are made to the model, a revised report is one click away.

We have found that most stress engineers not using ROHR2 prefer building the stress model from scratch.  This matches our experience that in most of the software (besides ROHR2), building the model from scratch seems to be preferable to avoid the clutter, disorganization, or in some cases mechanical discontinuities.  ROHR2’s tools are so unique in being able to “clean up” even messy imports that we save our clients over 50% for jobs done in ROHR2 compared to other pipe stress programs.

In most pipe stress programs, the loads are all applied at once to the stress model.  But in so doing, one misses important loads that occur.  Take, for example, the resistance forces to friction.  They are applied as static forces resisting the movement from ambient to operating temperature.  But what about the resistances from operating to ambient?  A follow-up load case takes any other load case as a starting point to which new loads can then be applied.  In this way, what actually happens in real life is correctly represented by the stress model, identifying problems in the design stage.

A linear boundary condition would be a support or restraint that provides a linear relationship between force and movement.  For example, a spring hanger or rigid rod hanger would provide such a boundary condition.  Gaps and/or friction are non-linearities that provide certain challenges in the stress analysis.  The static analysis is incomplete without “follow-up” load cases that ROHR2 can create to properly bracket the effects of the non-linearities.  For the dynamic analyses (when using modal / time-history methods), the non-linearities must be linearized since the mathematics driving these methods is linear.  This can lead to a significant divergence between calculated (linear) results and actual (non-linear) behavior.  ROHR2 includes two dynamic modules seamlessly integrated offering both the linear methods as well as an advanced numerical method to properly model the non-linear boundary conditions.

Mechanical discontinuities after importing is generally the result of improper modeling in the design software but is no problem to fix if you use ROHR2.  By displaying the node numbers for the “end points” only you will be able to quickly visually identify end points where there should be none.  Using the move command, the one endpoint is moved to the other which connects the two elements that were previously not connected.  There is also a setting to automatically merge nodes that are closer than a set distance if that option is desired.

ROHR2fesu is a module that is seamlessly integrated into ROHR2 where finite element models can be incorporated into the beam-theory analysis.  Components can be modeled for which flexibility and stress intensification factors are not readily available in the code.  For nozzles, where one would otherwise assume overly conservative stiffnesses, a more realistic stiffness can be calculated.

ROHR2’s automatic revision management does it all for you – seamlessly.  This has been another feature that has really stood out to us in the increasingly complex world of QA/QC requirements.

As soon as you click “File / Save As”, ROHR2 automatically creates a new subdirectory for the next revision – if there is a check mark next to “Enable revision management” (which is the default).  By describing the revision the available space, all revisions are properly documented avoiding potential for future confusion.

Sigma acquired the ROHR2 license rights in 2000 from EDS Software and continues to develop and maintain ROHR2.  (Ingenieurgesellschaft means engineering company.)

ROHR2 was developed in the late 1960’s by one of the most reputable software vendors in Europe – “mbp” in Germany.  (ROHR means PIPE in German.)  It was first commercially available in 1970.

PSI is Sigma’s sales partner for the US and Canada offering a full line-up of sales, support and training.  PSI was a user of ROHR2 for 20 years before becoming the US dealer and continues to use ROHR2 in their engineering work.

Yes, PSI has deep roots in engineering services and has extensive experience with many of the pipe stress programs on the market.  We can speak to specific strengths and weaknesses as well as offer practical engineering support along with specific software support.