An analysis can become more complicated than it
needs to be when the model is composed of multiple 
bodies interacting with each other.

Simplifications discussed:
	1) Symmetry
	2) Bonding Bolt Heads
	3) Mesh Control
	4) Gasket Space
	5) Classical Calcs

1) Symmetry - As with many analyses, the following valve by Stainless Valve Co can be simplified by cuts along the two planes of symmetry as shown.

2) Bonding Bolt Heads - In many cases, the interaction between components can be considered "bonded" instead of using sliding contracts, which reduces calculation time. For this example, the bolt heads were considered bonded to their mating surface. Artificial stresses are generated by the method of preload approximation, and these stresses should be neglected. (See Preload Article.)

3) Mesh Control - A smaller mesh size was only used in the areas requiring greater calculation refinements (bolts). This improves calculation time while maintaining accuracy. The weldneck flange and its bolts have a coarser mesh because they are covered by classical calculations, as noted in section 5 below.

4) Gasket Space - This model contains a gasketted flange, which has been approximated in the FEA by a representative space between the flange and plate. To simulate the flange loads, the Appendix-2 forces were applied to both the flange and the plate. Since the bolts are bonded to the outer surface of the flange, one continuous mesh was created.

5) Classical Calcs - The weldneck flange and its attachment bolts are covered by Appendix 2 calculations and do no require a detailed FEA analysis. They are included to simulate the interactions with the valve, but are hidden in this view for clarity.