Procedure 5-1 Design of Internal Support Beds

This procedure can be used to design aU the various components of a support structure consisting of the 

Beams should never be welded directly to the vessel wall because of the restraint they would impose on vessel growth. All of the methods listed above will allow for the radial expansion of the vessel due to temperature and pressure. Slotted holes in the clip or for the bolting attaching the beam to a beam seat, allow for expansion. 

Beam seats and clips allow the top flange, or top of beam, to be level with the top of the support ring. This is a very convenient feature for this type of support. In effect, it creates a level surface to support the grating or tray plates. Conversely, if the beams are supported by the support ring, then the bottom flange of the beam will sit on top of the support ring. For most applications this would be unacceptable. In order to make the 

There is really no limit to the number of cross beams that may he utilized, however this procedure only illustrates the use of up to eight beams. If access through the center of the vessel is a concern, then only an even number of beams can be used. A center beam would impede access. Beams can be solid members, welded I-Beam t5rpe, welded T-type, or open, lattice type structures. 

Lattice beams are desirable, if possible, due to their light weight. Where internals are stainless steel to prevent or minimize corrosion, they will also reduce cost. Unlike solid or built-up beams, the top and bottom members of a lattice beam have distinct functions. The bottom chord is the tension only member. The top chord is a compression only member. This is for beams above the line of support. For beams below the line of support, the reverse would be true. 

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