Construction
Plate Heat Exchangers consist of a number of very thin corrugated stainless steel/titanium heat transfer plates clamped together in a frame. Every second channel is open to the same fluid. Between each pair of plates there is a nitrile rubber gasket, which prevents the fluids from mixing and from leaking to the surroundings. Heat is thus transferred from the warm fluid to the colder fluid via the thin stainless steel/titanium plate. The corrugations support the plates against differential pressure and create a turbulent flow in the channels. In turn, the turbulent flow provides high heat transfer efficiency, making the plate heat exchanger very compact compared with the traditional shell-and-tube heat exchanger. In most cases the plate type heat exchanger is the most efficient heat exchanger. Generally it offers the best solution to heating and cooling applications since it can better handle the widest pressure and temperature limits.
Advantages
-Plate Heat Exchangers utilize the thinnest material for the heat transfer surface that in turn gives optimum heat transfer, since the heat only has to penetrate thin material.
-High turbulence in the medium that in turn gives a higher convection, which results in efficient heat transfer between the media. The consequence of this higher heat transfer coefficient per unit area is not only a smaller surface area requirement but also a more efficient process.
-Higher turbulence also gives a self-cleaning effect. Therefore, when compared to the traditional shell and tube heat exchanger, the fouling of the heat transfer surfaces is considerably reduced. This means that the plate heat exchanger can remain in service far longer between cleaning intervals.
-The heat exchanger consists of a framework of plates, more plates can easily be added to increase capacity or less plates to decrease capacity.
-Compact construction.
-Plates can be separated for easy cleaning.
-Sock filters on the suction side filter most debris allowing the heat exchanger to run longer without maintenance.
Disadvantages
-High initial cost.
-Do not work well under high pressure rates.
The shield is used to seal the inner ball bearing components. The shield prevents particle and contamination ingress as well as retaining the grease used to fill the free bearing internal spaces.
The rolling-elements of a rolling-element bearing ride on races. The large race that goes into a bore is called the outer race, and the small race that the shaft rides in is called the inner race. Read more ...
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Bearing balls are special highly spherical and smooth balls, most commonly used in ball bearings, but also used as components in things like freewheel mechanisms. The balls come in many different grades. These grades are defined by bodies such as the American Bearing Manufacturers Association (ABMA), a body which sets standards for the precision of bearing balls. They are manufactured in machines designed specially for the job.
In 2008, the United States produced 5.778 billion bearing balls. Read more ...
The rolling-elements of a rolling-element bearing ride on races. The large race that goes into a bore is called the outer race, and the small race that the shaft rides in is called the inner race. Read more ...
The shield is used to seal the inner ball bearing components. The shield prevents particle and contamination ingress as well as retaining the grease used to fill the free bearing internal spaces.
