2.1 Shell-and-Tube Exchangers 1 More than 65% of the market share (in the late 1990s) in process and petrochemical industry heat exchangers is held by the shell-and-tube heat exchanger, for the following reasons: its versatility for handling a wide range of operating conditions with a variety of materials, design experience of about 100 years. proven design methods and design practice with codes and standards. The selection of an appropriate shell and-tube heat exchanger is achieved by a judicious choice of exchanger configura- tion. geometrical parameters, materials, and the right" design. Next we summarize some guidelines on all these considerations qualitatively to provide the feel for the right design for a given application. The major components of a shell-and-tube exchanger are tubes, battles, sh front-end head, read-end head, and tubesheets Depending on the applications, a specific combination of geometrical variables or types associated with each component is selected. Some guidelines are provided below. For further details on geometrical dimensions and additional guidelines, refer to TEMA (1999)