About plate heat exchanger

Plate heat exchanger is a new highly efficient heat exchanger consists of a series of corrugated sheet metal with a certain shape made ​​of stacked. Forming a thin rectangular plate between the various channels through half a slice of heat exchange. Compared with the conventional shell and tube heat exchanger, at the same flow resistance and pump power consumption, much higher heat transfer coefficient has replaced shell and tube heat exchanger within the scope of the trend. Plate for plate heat exchanger is pressed against a metal sheet into a heat exchange plate having a corrugated shape and then stacked, with a splint, bolt made of a heat exchanger. Narrow and tortuous passage of the working fluid between the two plates forming flowing. Hot and cold fluid passes through the flow channel, the middle of a separate fluid compartment plates, and carried by the plate heat exchanger.

Under normal circumstances, we mainly to distinguish the structure of plate heat exchanger, which is based on the shape to distinguish, can be divided into four categories: 1, detachable plate heat exchanger (called with sealing gasket plate heat exchanger) , 2, welded plate heat exchangers, 3, spiral plate heat exchanger, 4, coil heat exchangers (also known as cellular heat exchanger 5).
Plate heat exchanger comprises two main frame and plate components. Thin sheet made ​​from various materials with various forms of pressure abrasive into corrugated shapes, and in the four corners of the opening plate angular aperture for the medium flow path. Perimeter and corner of the plate hole sealed with a rubber gasket. Framework consists of fixed clamping plate, activities pressing plate, the upper and lower guide rod and clamping bolts and the like. Plate heat exchanger is superimposed in the form of plates mounted on the fixed clamping plate, pressing the middle plate activity, and then clamped together with the clamping bolt.

Plate heat exchanger with a heat transfer coefficient, pressure drop is small, compact, light weight, small footprint, easy area and process combinations, parts versatility, choose materials, and easy to implement wide-scale production, etc., have been widely used in food, machinery, metallurgy, petrochemical and shipbuilding, and become the city's leading central heating engineering heat transfer equipment. In order to ensure the normal operation of the plate heat exchanger, extended key components (such as plates, pads) of life, understand the emergence of plate heat exchanger failure and its causes and treatment is very important.
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Fuse switch Introduction

Fuses (fuse) means that when the current exceeds a predetermined value, the heat generated by itself to the melt blown off an electrical circuit. Fuse switch for some time after the value of its self-generated heat so that according to the current exceeds the melt melted, so that the circuit is disconnected; using a current protector made of this principle. Fuse switch are widely used in high and low voltage power distribution and control systems and electrical equipment, as a short-circuit and over-current protection, is one of the most common protection devices. Fuse switch from the base and the cover (load melting device) composed of two parts, fuses generally vertical fuse rail, was a three-phase parallel enclosed structure, positive operation, covered by a transparent cover plate can be fitted directly observed the fuse-rated pieces of data, and indicates the operating state, the switch can be equipped with NH000 or NH00 fuse two kinds of body sizes. Fuse switch has compact, safe, reliable, easy loading and unloading fuse body, feel the operating force is small.
Fuses mainly from the melt, the housing and bearing three parts, which is a key element controlling the melt fusing characteristics. Material, size and shape determine the melt fusing characteristics. Melt material is divided into two types of low melting point and high melting point. Low melting point materials such as lead and lead alloys, its low melting point easily blown, due to its greater resistance, so the larger cross-sectional dimensions made melt and fuse metal vapor produced when more capacity is only applicable to low-scoring off the fuse devices. Refractory material such as copper, silver, and its high melting point, is not easy to fuse, but due to its low resistivity, can be made of a low melting point melt-sectional dimensions smaller than, less metal vapor is generated when the fuse is suitable for high breaking capacity fuses. Melt into filamentous shape and strip two. Changing variable cross-section shape can significantly change the fuse characteristics.
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About laser cutting machine

Laser cutting machine is called the energy of the laser beam is irradiated to the surface of a workpiece when the workpiece is released and evaporated to melt, in order to achieve cutting and engraving, with high precision, fast cutting, the cutting pattern is not limited to the limit, the automatic layout save material, cut smooth, low processing costs, will gradually improve or replace the traditional metal cutting process equipment. Laser cutting machine as a new tool to use increasingly sophisticated variety of industries, including laser cutting machine, laser engraving machine, laser marking machine, laser welding machine. Metal laser cutting machine is the use of high power density laser beam scans over the surface of the material, the material is heated in a very short time first million to several thousand degrees Celsius, melting or vaporization of the material, and then the high pressure gas from the molten or vaporized material cut seam blown away, to achieve the purpose of cutting material. Laser cutting, since the beam is not visible instead of the traditional mechanical knife, mechanical portion of the laser head without contact with the work, the work will not cause scratches on the surface of the work; Laser cutting speed, smooth incision, usually without subsequent processing; small cut heat-affected zone, the plate deformation is small, narrow kerf (0.1mm ~ 0.3mm); incision without mechanical stress, no cutting burr; high precision, repeatability, does not damage the material surface; CNC programming, processed any plan, you can format the entire board cut great, no open mold, economic saving.
Development of the laser industry, although a preliminary development, but in the international science and technology led to the development leap has been completed, and the same quality with outstanding than a high stage. Laser cutting machine in terms of market demand up to ten million, for a broad market added new vitality. In the development of the laser industry, while laser kits also entered the production of industrial equipment market, get rid of the over-reliance on foreign situation, to solve the domestic laser industry embarrassment. The rapid development of the domestic economy, has become a pillar industry of high laser market, and can reach more than 20% annual growth rate, as a new starting point for the global laser market, according to experts predict that the domestic market is still in laser rapid growth phase, You can double the increase during the next to the largest expansion of laser cutting equipment market, to fill the gaps, the domestic high-end laser equipment to get rid of the troubled state, becoming the mainstay of the international community.
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Aluminum extrusion methods

With the recent rapid development of science and technology as well as the industrial economy, the demand for aluminum welded structure is increasing, so the welding of aluminum also will be in-depth. Aluminum is widely used to promote the development of aluminum welding technology, welding technology while developing and expanding the applications of aluminum, aluminum welding technology is becoming one of the hot research.

Means for forming the profile is extruded. The first product based on the profile section design, manufacture molds, use a good round heated extruder die casting rods from extruding. Shihai in extruded aluminum with an air-cooled artificial aging process and subsequent hardening process to complete heat strengthened. Different grades can be heat strengthened alloys, different heat treatment system. To extend die life science, rational use of molds for production is one aspect can not be ignored. Since the extrusion die is extremely harsh working conditions in the production of extruded aluminum must take reasonable steps to ensure that the organization properties of the mold:
1, to take the appropriate extrusion speed
2, a reasonable choice extrusion temperature

Aluminum extrusion products with high strength, light weight, corrosion resistance, decorative, long life, rich colors and so on. Generally, a good product in 20 years without losing its surface light, not color. Aluminum extrusions is the industry's most widely used class of non-ferrous structural materials have been widely used in aviation, aerospace, automotive, machinery manufacturing, shipbuilding, construction, decoration and chemical industries.
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Maintenances for the TOP WATER CHILLER

The service life for the water chiller unit mostly depend on the good working condition and maintenece for the chiller system. For the Chiller, below points should be noted for the maintenance
1.The refrigerating water pump should not work if there is no water in the water tank; (For the chiller unit above 7.5 HP, there is a built-in water level protector in the water tank. While the water level is too low or the tank is empty, the water pump will be stopped automatically, and it displays the water-level fault code and alarm.)
2. The operating switches should be avoided frequently switching over. Pls turn off the main power when the machine did not work for a long time.
3. While the refrigerated-water temperature reaches to the set temperature, the compressor will stop.
4. In order to prevent the evaporator freezing, do not set temperature below 5℃;( except the low temperature chiller), Pls drain out the chilled medium off the machine when it did not work for a long time.
5. To make sure the best cooling efficiency and best working condition of the unit, please clean the condenser, evaporator and the water filter regularly, and confirm there are no adulterant and other obstruction.
6. Please turn off the chiller while it is alarming. And start chiller after the failures are removed according to the way stated in the Mannual.
7. Good ventilation and clean working condition will be better for the operation of air cooled chiller as along as keeping in high cooling efficiency.
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