Heat Exchanger Manufacturers

What are Heat Exchangers?

A heat exchanger is a mechanism used for transferring heat between two or more liquids. A heat exchanger is used for both heating and cooling. The liquids can be separated by a solid wall to avoid forming mixtures, or they can be directly in contact.

They are widely used in refrigeration, space heating, air conditioning, chemical plants, petrochemical plants, power stations, petroleum refineries, sewage treatment, and natural gas processing.

The classic instance of heat exchangers is found in internal combustion engines, in which a circulating liquid called engine coolant flows inside radiator coiling and external air flows outside the coiling, thereby cooling the coolant and heating the incoming external air.

Another instance is heat sinks, which are passive heat exchangers that transfer the heat generated by electronics or mechanical devices to fluid mediums, often liquid or air coolants.

Heat Exchanger Selection Considerations

While there is a huge variety of heat exchangers on the market, the appropriateness of each type in heat transfer between liquids depends on the requirements and specifications of the application. Those factors determine the best design of the required heat exchanger and impact the corresponding sizing and rating calculations.

Some factors that professionals keep in mind while choosing and designing a heat exchanger are:

• The type of liquid, the liquid stream, and its characteristics
• The required thermal outputs
• Size limitations
• Costs

Types of Heat Exchangers

The different types of heat exchangers include:

Finned Tube Heat Exchangers or Air Cooled Heat Exchangers

Finned tube heat exchangers, air cooled heat exchangers, dryers, or coolers work by flowing a fluid into an array of tubes while pumping air or gas over or around the pipes to cool the fluid down.

Sometimes finned tube heat exchangers, dryers, or coolers are hemmed in ductwork, and other times they are fully uncovered with air flowing above them. The efficiency of these devices is derived from their drawn-out surface – the fins protrude into the gas/air flow and increase the heat transfer capability of the structure. They are suitable for gas or air to fluid.

Shell and Tube Heat Exchangers

A shell and tube heat exchanger works by passing a cold or hot gas or fluid through an array of tubing (called a tube bundle) covered in a large metal shell. The counter-flowing cold or hot gas or fluid is pumped into the shell. This is where the heat transfer happens. They are suitable for fluid to gas or fluid to fluid.

Plate Heat Exchangers or Gasket Plate Heat Exchangers

A plate heat exchanger or gasket plate heat exchanger works by passing liquids through an array of plates that are compressed together side by side. They’re suitable for fluid to vapor or fluid to fluid.

Plate and Shell Heat Exchangers

It combines the plate heat exchanger with the shell and tube heat exchanger mechanism. The core of the heat exchanger comprises a wholly welded circular plate package made by compacting and cutting rounded plates, then welding them together. Nozzles carry the flow out and inside of the plate pack.

The wholly welded plate pack is made into an outer shell, which creates a second flow path. The plate and shell mechanism offers high heat transfers, high pressure, high operating temperatures, dense size, reduced fouling, and close-approach temperatures.

Adiabatic Wheel Heat Exchangers

These utilize an intermediate solid store or fluid to hold heat, which is then transferred to the heat exchanger’s other side to be released. Two examples consist of a big wheel with fine threading spinning through the cold and hot fluid and fluid heat exchangers.

Plate Fin Heat Exchangers

They use “sandwiched” channels with fins to improve the efficiency of the unit. The designs include counter-flow and crossflow coupled with different fin configurations like offset fins, wavy fins, and straight fins. They are usually made from aluminum alloys, which offer high heat transfer competence.

Dynamic Scraped Surface Heat Exchanger

This is mainly utilized for cooling or heating with high viscosity yields, crystallization operations, evaporation, and high fouling applications. Long operating times are attained due to continuous scraping of surfaces.

Direct Contact Heat Exchanger

These involve heat transfer between cold and hot flows of two phases without a separating wall. Such heat exchangers may be categorized as gas–liquid, immiscible fluid–fluid, solid–fluid, or solid–gas.

Microchannel Heat Exchangers

It is a multi-pass parallel flow heat exchanger with three major elements: manifolds (outlet and inlet), multiport tubes, and fins.

Pillow Plate Heat Exchangers

Pillow plate heat exchangers are commonly utilized in the dairy industry for milk cooling in large direct-expansion stainless steel tanks. Nearly the whole surface area of a bulk tank may be integrated using this heat exchanger.

Applications of Heat Exchangers

Many types of heat exchangers find application in an extensive range of industries, such as:

• ASME heat exchangers
• Automotive heat exchangers (typically as car radiators)
• Brewery heat exchangers
• Chemical heat exchangers
• Cryogenic heat exchangers
• Marine heat exchangers
• Power generation heat exchangers
• Refrigeration heat exchangers