In its simplest form, the double pipe heat exchanger, (also known as a concentric pipe, hairpin, jacked pipe and jacketed U-tube heat exchangers), consists of a single tube mounted inside another. One fluid flows in the inner pipe, while a second fluid flows in the outer pipe annuals.
Double pipe heat exchangers come into their own when a conventional shell and tube heat exchanger would be uneconomical. They are suited for applications where either low flow rates, large temperature cross or small duties with high flow rates are involved.
Their size makes them particularly suitable for applications where space is at a premium. Multiple units can be set up in either series or parallel and mounted vertically.
Their small diameter allows high pressure units to be built with thinner walls than would be achievable with conventional shell and tube heat exchangers.
A double tube heat exchanger is able to achieve pure counter current flow thus allowing for a temperature cross to be achieved whereby the cold fluid can be heated above the exit temperature of the hot fluid.
The use of flanged connections allows double pipe heat exchangers to be completely stripped down for cleaning and maintenance.
Graham Hart (Process Technology) Ltd. can supply a full range of services from thermal and mechanical design through to complete manufacture.