Advantages of Hairpin Heat Exchangers
It has a better thermal performance than a multi-pass heat exchanger, even for processes having very low EMTD (effective mean temperature difference).
As it is a U-tube design, metallic expansion joints are not required to absorb the differential expansion between the service channel and the product channel.
The U-radius of the hairpin itself is also an effective transfer length, unlike the elbow that would be needed to interconnect in series two shell and tube heat exchangers.
It allows a design with removable U-tube bundle but also completely welded.
The pressure drop in the product channel is lower than the one achieved in an equivalent multipass design.
It is a compact design, with low maintenance cost.