Tubes in tube heat exchangers are perfect for heat transfer between two fluids with different temperatures and pressure. They are mostly used in manufacturing industries where the heat treatment is exposed to fluids with high viscosity, fiber, density or solid particle contamination.
A tube-in-tube heat exchanger is also known as a double-tube heat exchanger, consisting of two concentric tubes. These heat exchangers are specifically designed for cooling or heating products with low-medium viscosity. Same as the shell and tube heat exchanger, tube in tube heat exchanger processes products without the risk of clogging. Follow this blog to learn everything you need to about this heat exchanger.
What Is Tube In Tube Heat Exchanger?
This is a type of heat exchanger designed with two concentric tubes. One of the tubes has a larger diameter than the other tube in tube heat exchanger. This allows unrestricted flow of products, making it the perfect type of heat exchanger for viscous fluids. As the fluids flow through the inner tube, the service fluid flows through the space between the two tubes in the surrounding shell.
These heat exchangers can successfully process the products with particles without worrying about clogging. The tubes have larger diameters which allow for a free flow. Furthermore, this double tube heat exchanger is dismountable, making it easy for mechanical cleaning. It also has a prolonged service life due to its corrosion-resistant construction materials.
The Working Principle Of Tube In Tube Heat Exchanger
This heat exchanger design can easily achieve counter current flow. This allows for a temperature switch, so the cold fluid is heated above the hot fluid outlet temperature. As a result, the cooled or heated fluid never gets into contact with the fluid it’s cooling or heating.
Moreover, the inner and outer tubes carry the cooled or heated fluid, a method known as an indirect heat transfer method. The outer tube’s fluid enters the tube from the opposite side to the fluid in the internal tube. This process is known as contraflow or counterflow.
A tube in a tube heat exchanger is mostly used in a manufacturing company in the preheating and cooling sections with the need for a direct steam injection heat exchanger. Heat exchangers use the indirect heat transfer method in the cooling and preheat sections. However, the final heating is through steam injection directly into the product. This process is also known as the direct steam infusion or injection.
Double Tube Heat Exchanger Design
The tube-in-tube heat exchanger has a reduced overall size, increased efficiency, and can prevent thermal fatigue due to its compact design. As a result, it’s the best heat exchanger equipment for low flow applications, high pressure and temperature. One major advantage of the tube-in-tube heat exchanger is that it’s highly customizable to fit any available installation footprint or any custom request the company might need.
Moreover, it also has a flanged connection, allowing this heat exchanger to be easily disassembled for easier cleaning and maintenance. Its design makes it one of the most used heat exchangers in several manufacturing companies for the ever-expanding wholesale replacement market.
Types Of Tubes In Tube Heat Exchanger
The double tube heat exchanger has three major types which can be used in various applications. These are as follows:
- Industrial Tube In Tube Heat Exchangers
This double tube heat exchanger has a corrugated inner tube to help increase heat transfer while reducing fouling. It’s the best type for industrial applications.
- Industrial Tube In Tube Heat Exchangers with a Removable Tube
This type has a removable inner tube that allows easier cleaning and faster inspection and reduces operational downtime for the high fouling products. It also has a concentric geometry, making it easy to work with fluids with particles without the problem of blockages. It also has a smooth, similar design to tube heat exchanger designs, making it more efficient.
- Sanitary Tube In Tube Heat Exchanger
This double tube heat exchanger has inner and outer coiled tubes. These designs meet the pharmaceutical industry’s high-quality hygienic standards and requirements. In addition, they don’t have any cross-contamination risks between their working fluids and the product.
These facts should give a clear understanding of what tube-in-tube heat exchangers are. It also has several applications and benefits, which makes it one of the most preferred tube heat exchangers. They also work great in environmental applications like sewage treatment, pasteurizing sludge, and more.
