Condenser floating head

The last bleeder to dry up completely was, of course, the one that had always been overlooked on the condenser floating head. 

Product column condenser shell and tube, floating head, heat transfer area 15 m2, design pressure 2 bar, materials stainless steel. 

Provision for thermal expansion. Because of the differences in temperature existing in condensers, expansion strains may be set up that are sufficiently severe to buckle the tubes or pull them loose from the tube sheets. The most common method of avoiding damage from expansion is the use of the floating-head construction, in which one of the tube sheets (and therefore one end of the tubes) is structurally independent of the shell. This principle is used in the condenser of Fig. 15.8. The figure shows how the tubes may expand or contract, independent of the shell. A perforated plate is set over the vapor inlet to prevent cutting of the tubes by drops of liquid that may be carried by the vapor. 

A program which will rate condensers, vaporizers and exchangers with two-phase flow in several different types of equipment is quite complex. The program presented here will be a relatively simple one which can be modified to include these refinements. Also, it is limited to a floating-head type exchanger with two or more tube passes and a single-pass shell. 

Other mappings can be altered in a similar fashion. For example, for the condenser, the mapping is altered from a shell-and-tube heat exchanger with a fixed tube sheet to one with a floating head. When the desired changes are completed, press OK to continue and wait for the equipment mapping and sizing to be completed. 

Process simulation units (that is, blocks, modules, or subroutines) are mapped into more descriptive models of process equipment (e.g., mapping a HEATX simulation unit into a floating-head, shell-and-tube heat exchanger mapping a RADFRAC simulation unit into a tray tower, complete with reboiler, condenser, reflux accumulator, etc.) and associated plant bulks, which include installation items, such as piping, instrumentation, insulation, paint, etc. 

A sketch was made of the bleeders (i.e., small drain valves) that were to be opened to check for water (Fig. 20-1). Note the location of the bleeder on the floating head of the overhead condenser. This particular drain valve had been overlooked in all previous attempts to dry out the tower. 

Install floating head pressure condenser controls. 

Figure 2.10 Floating head condenser. (1) Vapour inlet, (2) outlet for the not condensed vapour and condensate, (3) coolant inlet, and (4) coolant outlet.

Type Double Pipe Float. Head Reboiler Fixed TS Condenser Oi>ublc Pipe Dtiublc Pipe... 

What would happen to a steam reboiler if the float in the steam trap became stuck in a partly closed position, or if the steam trap were too small Water—that is, steam condensate—would start to back up into the channel head of the reboiler, as shown in Fig. 8.3. The bottom tubes of the reboiler bundle would become covered with water. The number of tubes exposed to the condensing steam would decrease. This would reduce the rate of steam condensation, and also the reboiler heat duty. 

Operators who have problems with loss of reboiler capacity often attribute these problems to condensate backup. This is usually true. To drop the level of water out of channel head, either the steam trap or the condensate drum is bypassed by putting the condensate to the sewer. Sometimes the float of the trap is sticking, but mostly the difficulty is an erratically high pressure in the condensate collection... 

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