Tubular Heat Exchangers
We supply from Hipex, an innovative Australian company that provides a full range of corrugated tubular heat exchangers.
These models include the polytube (shell and tube with corrugated tubes), double tube exchangers, and specialised units (mixchanger and regenerator) that are ideal for handling viscous and heat sensitive materials.
In a tubular heat exchanger, one set of tubes within the shell (called a tube bundle) carries one fluid, while the other runs through the shell, which is then able to transfer energy (heat) between them. Heat can flow in either direction.
Their construction means that tubular heat exchangers are especially suitable for duties involving viscous products, and potentially fouling liquids, and are also ideal as cleaning in place (CIP) heaters.
They are the most common type of heat exchanger in oil refineries and other large chemical processes, and are suited for higher-pressure applications.
Polytube (shell and tube with corrugated tubes)
A polytube heat exchanger is an array of tubes welded or bolted into a compact bundle within a shell (hence the name “shell and tube” heat exchangers).
Polytube heat exchangers are one of the most common heat exchangers, and are available in a range of sizes and styles to suit any heating or cooling application. From smaller units ideal for industrial food processing, or larger units used as oil heat exchangers, Heat Transfer can source the Hipex products you need.
In Hipex polytube heat exchangers the tubes are expanded and welded into the tube plates at the end of the heat exchanger. Units usually have corrugated shells. There are no gaskets to replace, meaning maintenance is minimised. What is created is a tube path that is more suitable for food products.
Polytube heat exchangers are versatile, and can be used for cooling, heating or steam heating where the corrugations give a stronger construction against thermal stresses. Tube plates can be built with a variety of different termination types.
Double tube exchangers
Double tube heat exchangers are one of the most simple and maintenance free forms of heat exchange equipment. They consist of two concentric tubes that form an inner path and an outer (annular) path between the two tubes.
As in most Hipex heat exchangers, the two tubes can be corrugated to promote better heat or energy transfer and to reduce stress on the machine.
These machines are ideal for steam heating and can handle large or fibrous products without blocking.
Some typical applications include:
- Effluent water
- Pet food
- Tomato salsa
- Vegetable soup
- Wine must
The double tube heat exchanger is available in a strippable version (most are fully welded). The inner tube can be removed from the outer jacket allowing visual inspection of all heat transfer surfaces.
The unit can therefore be used in regeneration applications with products on both sides of the heat exchanger.
Specialised units (such as mixchanger and regenerator)
The mixchanger heat exchanger is ideally suited for heating and cooling viscous food and chemical products. The unique design of the heat exchanger delivers performance unrivalled by conventional tubular heat exchangers.
The clearance within the mixchanger enables large particulates to be handled without blocking or a significant loss in efficiency. The heat exchanger’s distinctive continuous mixing capability provides a much greater rate of heat transfer than can be achieved with other types of heat exchanger.
Continuous mixing improves heat transfer and reduces pressure loss. When heating viscous products this achieves high heat transfer coefficients, where traditional methods of promoting turbulence have become inefficient.
There are no moving parts. The central mixing element of the heat exchanger ensures continuous mixing, improving heat transfer and reducing pressure loss. Because maintenance is minimal there are fewer production hold ups. A single product channel improves flow distribution, product uniformity and means it is easier to clean. This product has been thoroughly tested and proven.
Typical applications for the mixchanger include:
- Tomato paste, orange concentrate, jam, yoghurt fruit, chocolate spread
- Dairy desserts, custard, vegetable puree, milk concentrate, rice puddings
- Pasta sauce, mango puree, pet food
Regenerator / triple tube heat exchanger
Economically it makes sense to recover heat from a hot product stream and to pass it to an incoming cold stream. There are many methods of recovering heat from non-particulate fluids, but those containing particulates such as pulpy juice from fruit and vegetables pose a problem.
The regenerator (or triple tube) efficiently reuses heat by providing two opposing fluid paths which are wider than in conventional annular or wide gap heat exchangers, minimising blockages with difficult products.
The tubes are sealed into the special headers with the use of two o-ring seals. An external weep detection port is present between these two o-rings allowing for the detection of a seal failure.
Hipex heat regenerators offer an ecofriendly solution with superior energy efficiency. They will maximise savings while maintaining the performance required in your regeneration applications.
Heat Transfer examples of applications in the market
Bowl liquor heaters for wool scouring plants. Units are made to order to fit the exact dimensions of the unit they will replace. Generally these units have steam heating wool scour liquor circulating around the washing bowls. They are normally double tube units with steam in the outer layer and liquor in the inner tube.
Special units manufactured for packaging companies which specialise in bag-in-box type solutions. These are double tube units (DT type) with inner tubes in SAF 2205 to give higher resistance to corrosion.
Polytube (PT) model units supplied for paua processing facilities, using duplex stainless tubes to cope with the salty environment. Steam / salty water heaters.
PT models typically supplied for steam / water heating duties as an alternative to plate type heat exchangers. These are all supplied with an expansion bellows to cope with the thermal stresses with steam. This is a much better solution than a plate type – there are no gaskets to replace. Gaskets can deteriorate with steam temperatures and can cause failure.
PT models supplied for crate wash applications in meat processing facilities. Water is heated to the correct temperature to wash crates that are then used to hold product. It is important to achieve the correct level of sterilisation to satisfy MPI requirements.
Heat recovery units of DT design to recover heat from a waste stream in meat processing facilities. The DT type is necessary because of particles in the waste product and having a single flow channel ensures no chance of channelling and blockage. The recovered heat preheats water for use in factories.
A specially designed PT unit for a dairy product development factory, chilling milk products with glycol. This plant has been exported to the northern hemisphere.
Heat Transfer are able to source all of these Hipex heat exchangers in a range of sizes and lengths. Contact us for a custom designed product perfect for your needs.