BLANKING-OFF REFORMER TUBES DURING PLANT OPERATION

Abstract

This chapter presents the results of experiments conducted to study blanking-off reformer tubes during plant operation. When a reformer tube splits during service, the loss of gas through the leak is not necessarily intolerable but the leaking gas ignites inside the furnace and causes overheating of the surroundings. To prevent damage to the refractories and to the neighboring tubes, it is necessary to isolate the failed tube. To achieve this, either the design must make provision for shutting off any individual tube or, if simple welded up connections are used, the whole unit must be shutdown and cooled so that the failed tube can be cut out and replaced, or the connections plugged by welding. The commercially available devices for low-temperature service are hydraulically operated that is an advantage, but their frames have to be dismantled and then reassembled on the pipe to be squeezed. The results show that blanking-off failed reformer tubes without having to shut the plant down, by squeezing the inlet and outlet pigtails at temperature and under pressure is possible.