H₂W United Testimony for ROHR2

H2W United is a specialist engineering company with proven track record providing cost-effective solutions for more complex projects in hydrocarbon processing. There is a fair amount of the piping that we design or modify for which a piping stress analysis is required to ensure that the stresses and loads on equipment connections do not exceed the allowable.

We are always looking at ways to improve our work flow in our effort to provide cost-effective solutions for our clients. There was clearly a significant task that was being performed twice: that is, building the geometry of the piping that was being evaluated for pipe stress. First our designers model the piping in 3D design software; then it is re-modeled in the stress program. For simple geometry, importing the piping information to the stress program seemed to work alright but the savings was not significant. Importing larger, branched piping systems resulted in unsatisfactory results and we kept reverting to re-building the geometry in the pipe stress program.

Some years back we were introduced to ROHR2 as the pipe stress program to end our importing frustrations. At first we were reluctant to switch from a program that was considered by many to be the “gold standard”, but since ROHR2 could also export files in the other program’s format, the risk seemed containable. In fact, we first used ROHR2 only as an import/export “bridge” between the design and stress software – which already saved a lot of time as we gained confidence in ROHR2. When we looked into the history of ROHR2, we were surprised to find it has existed for nearly 50 years with continual development and impressive credentials.

For years now, ROHR2 has been our program of choice and has continued to prove its value by giving us the ability to import the geometry of very large complex piping systems with minimal effort. On many systems, this ability has cut the cost of analysis in half compared to building and checking a second model, not to mention eliminating a potential error source.

Last year we needed to model vessel nozzles in finite elements as part of the pipe stress evaluation to determine nozzle stiffnesses and shell stresses. For this analysis, we used ROHR2fesu along with ROHR2, where the beam model (the piping in ROHR2) and the finite element model (the nozzle and vessel in ROHR2fesu) were connected and calculated in the same run. This experience underscored our growing awareness that the developers of ROHR2 are tuned into the practical, relevant issues that engineering businesses face in this competitive marketplace.

— Mike Hegarty, PE, Partner, H2W United