We have noticed what appears to be an error with the CAESAR II graphics when modelling vertical skewed pipe supports:

Scenario

Model a 42" line 100,000m long running along the Z-axis, with the Y-axis vertical.
Place an anchor at each end of the model and place a skewed "+Y" support every 10,000m along the line as follows:
+Y (0.3,0.9539,0).

Using the 3-D graphics view the pipe end on, (ie in the +X, +Y plane). The pipe support is located on the RHS (+X) of the pipe, hence one would expect the pipeline displacement under gravity to be in the -X, -Y direction.

Now analyse the model using the recommended load cases and view the "W + P1" loadcase displacement report.

The results show the deflections of the pipeline to be in the +X, +Y direction.

After much double checking of the cosine vectors defining the skewed pipe support we have finally decided that the CAESAR II graphics appear to be showing the pipe support on the wrong side of the pipe.

This error only seems to effect the X-Cosine. We retested the system with the pipe running along the X-Axis and define the "+Y" vector as "+Y(0,.9539,0.3)" and the skewed pipe support is shown correctly. We have also double checked the system with the Z axis vertical, again the problem occurs when there is an X-Cosine defined with a +Z support.

While I appreciate that not many people may model skewed vertical pipe supports, we are using CAESAR II to model cross country steam lines. The design of the pipe supports and the slope of the pipeline results in us modelling the vertical supports such they are perpendicular to the pipe at all times hence the use of skewed pipe supports.

When the pipe slope is small this graphical error is not too noticeable, however as the slope gets steeper the error becomes more and more apparent. While we are happy that we have modelled the pipe supports correctly our client would take one look at our model and say we have made a mistake.

Is there any patch available to fix this? Has this error been fixed in the next release of CAESAR II?


Thanks

This problem was discovered about 3 weeks ago. It has been fixed in Version 4.50, which is currently at the duplicators.

This is just a graphical representation that is misleading for skewed +Y type; the calculation is correct. In addition, when using cosines for skewed restraints in CAESAR II, it does not matter what particular restraint type to use (X, Y, or Z). Suggestion: use +X(0.3, 0.9539, 0) instead of +Y(...) to acquire the correct graphics...