Why we use U-type or hairpin construction in double pipe heat Exchanger? Why do not we use straight double pipe heat exchanger?

Most common are U-type or hairpin constructions. Due to the need of a removable bundle construction and the need for the ability to handle differential thermal expansions the exchanger is implemented in two parts. In figure 2 the fluids enter and leave the exchanger by the four nozzles on the right while the exchanger can freely expand to the left which makes the of expansion joints to the other machinery superfluous and makes demounting much easier.

 

U-type or hairpin construction for a double pipe heat exchanger

 

Advantages, disadvantages and applications of Double pipe heat Exchangers?(Click Here)