Suggest you go to www.aft.com. Consider their Fathom and Impulse software. The cost of this software will be saved in the time you will spend deriving solutions for the work you have in mind.

If you want to do stress analysis then go to www.pipepak.com. this package is so user freindly I use it for clod pipe systems to determine loading on supports.

For support design go to www.lisega.de and download their Licad software for free. great for spring hangar/snubber/constant load support design.

Control and relief valve selction I use Valtek/Fisher/Tyco/Farris software that is also freely available.

I am a one man operation that works for many major customers throughout SE Asia and I find this arsenal of software beats writing your own. I also use Mathcad but am thinking of going back to TK Solver as the way that works is more in tune with an engineers brain. Mathcad is more for the mathmatician.

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Mathematica is a program I tried hard with. It has  a very steep learning curve. I gave up.

MathCad I have used since version 1 (well I actually started with the demo which was a bit earlier).

In my opinion it has become slightly too complex for its own good these days - the extra features are fantastic, but the user interface has got worse. You may find that if your users haven't used earlier versions that they are happy with the latest user interface, I suspect most of my problems in adapting come from years of using v3.1

I still think that its output is the best I have seen - a non-user can follow the logic and read the equations directly.

Matlab and its freeware equivalents - Scilab, Maxima and Octave, are all very powerful, not as hard to learn as Mathematica, but still pretty inscrutable to the novice.

For general purpose engineering calculations I really think you'll find MathCad hard to beat.

Cheers

Greg Locock

I've used Mathcad since v3, I haven't noticed any obvious degradation in the user interface.  I think that used as intended, which is a graphical math scribble pad, it's unparalleled and unequaled.

You can do some fairly complex calculations, but as the first poster indicates, there is some NRE involved if someone hasn't already done the work.

In some cases, we use Mathcad to augment other more specialized programs.  I've got a program that does sensor predictions, but the output interface sucks and doesn't have the resolution that I want, so I export the data to Mathcad and postprocess it.

Mathcad's graph outputs are somewhat limited, so we use Excel or other graphing programs for final output.

For quick and dirty calculations, particularly involving units and conversions, Mathcad is excellent.  We use m/s, mph, kt, km/hr in our work, sometimes simultaneously, so having a program that works the units transparently is a great time and headache saver.

I think that you'll find that no single package will do everything you need.  The best you can hope for is to use a relatively small suite of tools to do the job.

TTFN

Thanks for your replies and for sharing your experiences.
In fact, we do use several tools to performing the tasks I mentioned earlier, ranging from Excel & VB to specific applications for valves.
The problem we normally have to cope with is that we must document all steps involved in the calculations and present the results in a way every mortal could understand, so, in many cases, I am forced to transfer
- hypotheses
- equations
- results
- graphs
from any other application (mainly Excel ) to MS Word to have a neat output .
Working with an old 2.5 version of MathCad I realized that all the process from the problem formulation to the graphs showing results could be performed within an only application and formulated in a natural (mathematical) language. Reusability, not only integration, is also the key here.  
In fact, I still keep many files from engineerig calculations I developed some years ago.
But, when thinking (finally) in an upgrade, I found no prices differences between Mathematica and MathCad, that's why I posted the question.
According to your comments, think that staying in a new version of MathCad will be the best choice.
Thanks

I think you will find that TK solver has the ability to provide Mathcad like presentations and allow you to do the engineering equations in the background. The beauty of TK Solver is that if you have twenty variables and now any of the nineteen you find the twentieth. Its great for backsolving.

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