Fixed tube Sheet heat exchangers are the one that are very much
used in process chemical industries and refinery services, as there
is absolutely no chance for intermixing of fluids. This type of
heat exchanger is employed where even slightest intermixing of
fluids cannot be tolerated. A fixed-tubesheet heat exchanger has
straight tubes that are secured at both ends to tube sheets welded
to the shell. The construction may have removable channel covers ,
bonnet-type channel covers , or integral tube sheets. The principal
advantage of the fixedtubesheet construction is its low cost because
of its simple construction. In fact, the fixed tube sheet is the
least expensive construction type, as long as no expansion joints
required. Specifications : The Fixed Tube sheet
design consists of two stationary tube sheets attached to the
shell. The bundle of straight tubes is connected between the tube
sheets and contain baffles to direct the flow around the tubes in
order to generate the required heat transfer. A head assembly is
attached to each tube sheet.
The U-tube design consists of straight length
tubes bent into a U-shape with both ends terminating at the tube
sheet. The tube bundle is fitted with supports or flow baffles. The
tube sheet/tube bundle is placed in the shell and bolted between
the head flange and body flange. A head assembly is required to
direct the fluid into and out of the tube bundle. This
configuration allows for the entire tube bundle to be
removable.
