This Section is concerned with the consequences of tube side failure in shell-and-tube heat exchangers. The tube side carries the high pressure (HP) fluid and the shell side the low pressure (LP) fluid. Failure of the tubes would, therefore, result in passage of tube side fluid into the shell side. What is written below is based closely on a set of Guidelines published by the Institute of Petroleum in 2000 Institute of Petroleum (2000).

The scenario leading to tube failures are described in Section 496A. design and assessment of units in Section 496B and aspects of relief system design are discussed in Section 496C. Finally, in Section 496C, experimental studies aimed at validating the recommended methodology for design are outlined.

A. Tube failure scenarios

There are two tube failure scenarios:

• A bleed leak (perforated tubes). This may form a source of contamination into the low pressure (LP) fluid system or in the worst case might escalate into a serious tube rupture;
• A tube rupture, which is normally assumed as a worst case having an escape route into the LP side equal to twice the area or the bore of one tube.