What is a double tube heat exchanger?
A double tube, or tube within a tube, heat exchanger is used for efficient heat transfer between two fluids. Double tube heat exchangers are designed whereby one tube is concentrically positioned within a larger tube. The product flows through the inner tube and the service fluid flows through the surrounding shell.
How many tubes can be plugged in a heat exchanger?
Roughly 9% of the tubes can be plugged in. If more than 10% of tubes are to be plugged, one can do some calculations to see if the required heat transfer is achieved.
What is the difference between double pipe and shell and tube heat exchanger?
Double pipe heat exchanger consists of two concentric pipes of different diameters. One pipe is for hot fluid and another is for cold fluid. Shell and tube heat exchanger consists of a shell in which large number of parallel tubes are present. One fluid hot or cold flow in shell and other hot or cold flow in the tubes.
What is the most efficient heat exchanger?
Plate exchanger is the most efficient due to turbulent flow on both sides. High heat-transfer coefficient and high turbulence due to even flow distribution are important. However, a plate heat exchanger regenerator is restricted to low viscosities. Plate exchangers fulfill these requirements best.
What is tube in tube heat exchanger?
The equipment consists of a single tube mounted inside an outer shell tube, so that the product medium flows counter-current through the inner tube, with the service medium around it. The unit features a fully welded construction with a bellow-on-shell tube to absorb thermal expansion.
What are shell and tube heat exchangers used for?
Shell and tube heat exchangers are widely used in applications, which require cooling, or heating large volume of process fluids or gases. There are a number of different types of shell and tube heat exchanger designs to meet several process needs in virtually every industry.
How many tubes can I plug in my shell and tube heat exchanger?
A question I am asked frequently is: “How many tubes can I plug in my heat exchanger?” The general consensus of most plant engineers and maintenance personnel is that 10% of the unit ( heat exchanger) can be plugged without losing efficiency.
What is tube plugging in heat exchanger?
Heat exchanger tube plugs are used to seal leaking heat exchanger tubes, thus preventing damage to adjacent tubes, and keeping the efficiency on an aging exchanger as high as possible. Torq N’ Seal® Heat Exchanger Tube Plugs offer a fast, simple, and effective way to seal leaking heat exchangers up to 7,000 psi.
Which is better double pipe or shell and tube?
When to use double pipe heat exchanger and shell and tube heat exchanger? Double pipe heat exchangers are used when the heat transfer area is small say up to 14 m2. As the numbers of tubes are more in a shell and tube HE, we can expect a higher turbulence which will result in higher heat transfer rates.
What is the main disadvantage of double pipe heat exchanger over the shell & tube heat exchanger?
The disadvantage of the double-pipe heat exchanger is that it covers a large area. At the same time, the metal consumption per unit heat transfer area is much, about 5 times that of the shell-and-tube heat exchanger. There are many pipe joints, which are easy to leak and large flow resistance.
What are the 3 types of heat exchangers?
Types of Heat Exchangers
- Shell and tube heat exchangers.
- Double pipe heat exchangers.
- Plate heat exchangers.
- Condensers, evaporators, and boilers.
How do I choose a good heat exchanger?
Smaller footprint and greater scalability make plate heat exchangers the best choice in applications where space is limited or scale flexibility is required.
- Energy use. Plate heat exchangers are up to five times more efficient than shell-and-tube designs.
- Footprint.
- Ease of maintenance.
- Capacity adjustment.
- Capital expense.
How does fluid flow in a double pipe heat exchanger?
One fluid flows through the inner of a small pipe, and another fluid is between the two pipes, and that is how the inner pipe acts as a conductive barrier. The outside or shell side includes fluid flow passing on the inner side or tube side.
How are the tubes connected in a double tube sheet exchanger?
The conventional double-tube-sheet exchanger has two tube-sheets at both ends of the tubes. In general, adjacent tube-sheets are connected to each other with the help of the tubes. Alternatively, shroud shells can be used to cover the gap between two tube-sheets. In this case, leaked fluid from either side is collected in the shroud shell.
When do you expand the tube in a heat exchanger?
In general, tube expansion within the tube-sheet shall always be done after welding of tube-to-tube-sheet joints. This is mainly due to the following reasons: ■ Tube expansion (rolling) before welding may leave lubricant from the tube expander in the tube holes.
How is go gauge used in double tube sheet heat exchanger?
The GO gauge is used to ensure free entry of tubes in tube holes of both tube-sheets. Before tubing the assembly, check randomly in each quadrant of the tube-sheet layout to verify that the gauge enters freely, which confirms concentricity of holes.