Heat exchangers, in the broadest sense, devices that provide heat transfer from the heated carrier to carrier with a lower temperature. Varieties of heat exchangers there are so many. For example, in surface heat exchangers heating medium and coolant separated himself very thin wall. An example is the automobile radiator, where the water engine cooling system and cold air separated on different sides of the walls of the grid of thin copper or brass radiator tubes. Flows of heating and heated materials are in direct contact with each other in the mixing heat exchangers. Here as example, you can use the jet condenser, where condensation of water vapor for use sprayed water. In the flue heat exchangers after combustion of the fuel flow of hot gases appears.
A typical example – in steam boilers and domestic hot water heating boilers are considered. There is also a classification of heat exchangers based on differences in their structures. Very common heat exchangers tubular type. Equally popular with advanced surface heat exchangers: plate-like or ribbed. Heat exchange surface area is greatly increased by the use of transverse ribs. Nevertheless, surface edges are less efficient with respect to heat than the surface of the pipe itself. But well-designed ribbed heat exchanger is more compact than the same machine without transverse ribs.
Thus, it has a higher heat transfer rate per unit volume. Depending on the purpose, stand types of heat exchangers: shell and tube heat exchangers (main elements of their tube bundles are collected in the tube sheet and placed in the body, pipes and tube ends are attached to the flare tube sheets, welding, soldering), plate heat exchangers (made up of individual plates delimited by rubber pads, two end cameras, frame and mounting screws), Twisted (surface heating comes from a series of concentric coils, encased and contained within certain heads, fluids move in tube and annulus), spiral (the heating surface is formed by two thin metal plates welded to the separator (cores) and rolled in a spiral) Air, water heat exchangers are made even pool-type heat exchangers. The choice of heat transfer equipment by highly individual, in accordance with the requirements of the technological chain of production customer, depending on how, what media will work machine, in which seismic and climatic conditions, it should work, as will be maintained in operation. Since most popular today are the collapsible-type heat exchangers, characterized by small hydraulic resistance, ease of installation, compactness, ease of manufacture, intense heat transfer and decontamination. Oil, gas and petrochemical production is impossible without a spiral, twisted, shell and tube heat exchangers and high conductivity, heat exchangers, so-called "pipe in pipe". Unbelievable, but fact: the largest production volume and weight of devices for gas, chemical, petroleum is not a mass, plants produce them on request only, at several instances in accordance with the contract. There are of course approved projects of manufacturing heat exchangers, but every single order begins his journey in the design bureau of the plant, which prepares all project documentation. Experienced engineers are preparing necessary drawings and diagrams of production, which in future is the creation of each individual unit.
