Moving Beyond WRC & Zick

Finite element technology moves beyond the limitations of  WRC107, WR297 and Zick to allow engineers to design safer equipment more efficiently and cost-effectively. 

Only NozzlePRO allows you to build WRC and Zick geometries with a few clicks of your mouse.  When you consider that  NozzlePRO provides finite element results from the SAME information needed to run a WRC or Zick analysis, the advantage is clear.

Making FEA Work for You

NozzlePRO generates graphical and tabular results that clearly represent your system.  The graphics can be viewed with DirectX and vividly display the results of pressure, moments, temperature and loads.

The interactive toolbox allows the user to direct and manipulate models.

The tabular results give flexibilities and SIFs that can be put back into a piping analysis package, adding greater accuracy and better results.

A primary advantage of NozzlePRO is the automated ASME Code Compliance reports.  There is no need to perform additional post-processing since NozzlePRO reports stresses with comparisons to the ASME Section VIII – Division 2 stress categories.

Nozzles, Saddles, Pipe Shoes & Clips

NozzlePRO is designed to quickly and easily evaluate nozzles, saddles, pipe shoes and clips.  A variety of head types are allowed including spherical, elliptical, ASME, dished, cylindrical and conical.  A minimum number of values must be input to generate the model.

The engineer is able to include thermal, weight, operating, occasional, pressure, wind and earthquake loads.  Within minutes you will be able to generate the following:

Axisymmetric and Brick Models

NozzlePRO offers optional axisymmetric and brick modeling capability for select geometries.

This functionality was added to permit a more accurate analysis of cyclic pressure stresses in thickwalled intersections; and for geometries not directly amenable to shell solutions such as non-integral repads and overturning moments on skirts.  The brick capability also provides a basic steady state and transient heat transfer calculation with the automatic placement of Stress Classification Lines (SCL’s) and ASME Code stress evaluations.

Piping Elements

NozzlePRO permits the user to pipe away from any NozzlePRO piping junction in a head or cylinder to evaluate the effect of the thermal expansion on the nozzle. This capability results in a much more accurate evaluation of loads and displacements on the nozzle and in the piping system. Straight sections, elbows, bends, intersections and linear restraints may be included in the analysis.


When You Need to Use NozzlePRO 

  • When there are multiple thermal or operating loads acting on a nozzle.
  • When the d/D ratio for a loaded nozzle is greater than 0.5 and WRC 107 or 297 is considered for use.
  • When the t/T ratio for a loaded nozzle is less than 1.0 and WRC 107 or 297 is considered for use.
  • When the nozzle is pad reinforced and WRC 107 or 297 is considered for use.
  • When there are loads acting on a nozzle and run pipe simultaneously.
  • When the number of full range pressure cycles is greater than 7000 and the nozzle is subject to external loads.
  • When the D/T ratio is greater than 100 and SIFs or flexibilities are needed for a pipe stress program.
  • When the D/T ratio is greater than 100 and a dynamic analysis including the nozzle is to be performed using a piping program.
  • When a large lug is used in a heavily cyclic service.
  • When pad reinforced lugs, clips or other support are placed on the
  • knuckle radius of a dished head.  WRT 107 simplifications for pad reinforced rectangular lug attachments are fraught with potentially gross errors.
  • When seismic horizontal loads on vessel clips or box supports are to be evaluated.
  • When pad reinforced hillside nozzles subject to pressure and external loads.
  • When evaluating large run moments, but small branch moments in a piping system.
•  When there are overturning moments on skirts.•  When the effect of integral vs. non-integral pad on nozzle in head

should be studied.

•  When there are different thermal expansion coefficients or temperatures between the header and branch.

•  When the loads on nozzles are high because of the assumption that

the nozzle connection at the vessel is a rigid anchor.  Few connections

at vessels are rigid.  Even small rotations can significantly reduce the

calculated moment and stress.  Accurate flexibilities permit the actual

moment on the vessel nozzle to be calculated  and included in design.

•  When there is heat transfer in an axisymmetric model geometry.

•  When the effect of adding a radius to weld geometries on nozzles in

heads should be investigated.

•  When the analyst needs to run various model types, comparing results to determine the stability and accuracy of the solution. 

To verify FEA calculations, NozzlePRO allows nozzles in heads to be analyzed with shell, axisymmetric, or brick finite elements.


•  When horizontal vessels are saddle supported, with or without wear

plates, and including tapered saddles with many design options.

•  When evaluating the effects of axial or transverse loads due to internal

sloshing, wind loads, seismic loads, or general external loads.  Zick’s

methods do not consider either axial or transverse loads.

•  When designing pipe shoes for self-weight, liquid weight and axial