What are plate heat exchangers?
A plate heat exchanger is a type of heat exchanger that uses metal plates to transfer heat between two fluids. This has a major advantage over a conventional heat exchanger in that the fluids are exposed to a much larger surface area because the fluids are spread out over the plates.
How do plate heat exchangers work?
Plate heat exchangers stack multiple heat transfer plates inside a rigid frame and compressed them to form an arrangement of parallel flow channels with alternating hot and cold fluid.
The space between two adjacent plates forms the channel in which the fluid flows. Gaskets separate the plates to obstruct fluids from entering the alternating heat transfer plates.
Inlet and outlet holes at the corners of the plates allow hot and cold fluids through alternating channels in the exchanger so that a plate is always in contact on one side with the hot fluid and the other with the cold medium.
There must always be a temperature difference between the mediums. The heat lost from the hot medium equals the heat gained by the cold liquid.
Stainless steel is a commonly used metal for plates because of its ability to endure high temperatures and its high corrosion resistance. The inclination of the plate corrugations has a determining effect on thermal exchange and load losses.
Plates are typically made from steel or titanium, and you can see they have a pattern grooved or stamped into them. These patterns will strengthen the plates and increase the heat transfer surface area by creating a very turbulent flow inside them. Turbulent flow is good because it mixes the fluid, so the heat is distributed or averaged. If it was a smooth flow, the heat would build in some regions more than others.
Why are plate heat exchangers important?
PHEs are essential to the operation of many industries. They help regulate temperatures in food processing plants, chemical plants, and power stations.
Without them, these industries would be unable to function properly.
WHAT ARE THE BENEFITS OF USING PLATE HEAT EXCHANGERS?
There are many benefits to using plate heat exchangers in a heat exchange system.
Some of the most common reasons include the following:
- To transfer heat between two fluids without them coming into direct contact.
- To increase the heat transfer surface area for higher heat transfer.
- To improve the thermal efficiency of a system.
What are the disadvantages of PHEs?
Plate heat exchangers are unsuitable for high-pressure applications because the system pressure would expel the gaskets; this situation is referred to as a ‘gasket blow-out ‘. However, it is possible to get around this problem using a gasket-less design.
These designs usually use brazed or welded plates. Brazed and welded plate heat exchangers are more suitable for higher temperatures and pressure.
How often should plate heat exchangers be serviced?
It is recommended that PHEs should be serviced every 3 to 5 years. However, the replacement and service frequency will depend on many factors, such as the type of plate heat exchanger, the operating conditions, and the plate and gasket material quality.
What are the best plate heat exchangers for my application?
The best plate heat exchanger for your application will depend on many factors, such as the type of fluid, the operating conditions, and the plate, gasket material quality and heat transfer area needed.
Please contact us if you are unsure which plate heat exchanger is best for your application. We have over 100 years of combined experience repairing, designing, manufacturing, and installing PHEs across many industries.
Types of plate heat exchangers
There are four main types pf PHE to consider:
Gasketed plate heat exchangers have gaskets that seal the plates together. This prevents leaks. You can remove plates easily to clean or replace them if needed, saving money on maintenance costs.
Brazed plate heat exchangers are used in many industrial and refrigeration applications. They can be very efficient and compact, which makes them a highly economical choice. Using a stainless steel plate with copper brazing, this dynamic can be highly resistant to corrosion.
Welded plate heat exchangers are similar to gasket heat exchangers, but the plates can be welded together. They are durable and ideal when transferring fluids with high temperatures or corrosive materials. Since the plates are welded together, they cannot be cleaned like other heat exchangers.
Semi-Welded plate heat exchangers have some welded plates and some gasketed plates. The two plates are welded together and gasketed to other pairs within the heat exchanger. This results in an easy-to-service heat exchanger, and you can transfer more fluids throughout the system. Semi-Welded heat exchangers are great for transferring expensive materials because there is a low risk of fluid loss.
Other types of heat exchangers
There are many different heat exchangers, but the most common are plate and frame heat exchangers, shell and tube heat exchangers, and air-cooled heat exchangers.
A tube heat exchanger differs from PHEs because they have a much higher thermal efficiency. They also have a much lower pressure drop, which can be used in more applications.
WHAT MAKES WCRUK LTD DIFFERENT FROM OTHER SUPPLIERS?
We have over 100 years of combined experience repairing, designing, manufacturing, and installing PHEs across many industries.
We can help you with any size project, no matter how big or small.
Contact us today to learn more about our service, repair and new products!