With the wide application of LED, the problem of LED heat dissipation has been paid more and more attention. The heat dissipation performance of LED will directly affect the life of LED products. First, the LED heat dissipation misunderstanding analysis LED heat dissipation misunderstanding is mainly reflected in the following aspects: 1. Internal quantum efficiency is not high. That is, when electrons and holes recombine, photons cannot be generated in 100, and it is generally called a current leakage to lower the recombination rate of carriers in the PN region. The leakage current multiplied by the voltage is the power of this part, that is, it is converted into heat energy, but this part does not occupy the main component, because the internal photon efficiency is now close to 90. 2. The internally generated photons cannot be completely emitted to the outside of the chip and finally converted into Heat. This part is the main one, because the current external quantum efficiency is only about 30, and most of it is converted into heat. 3. Over-reliance on thermally conductive materials. Because of the high-tech materials used, the heat can be dissipated. Its practical ordinary aluminum heat dissipation, after repeated tests, the temperature of the heat sink is only 3-5 degrees Celsius higher than the bottom of the radiator. That is to say, if a material with excellent thermal conductivity can be used, the temperature can be lowered by 3-5 degrees Celsius when the thermal resistance is zero. 4. Superstition heat pipe. The heat pipe has a good thermal conductivity, which is beyond doubt. But the heat that is derived from the heat sink eventually needs to go tropical through air convection. If there are no fins that dissipate heat, the heat pipe will soon reach thermal equilibrium and the temperature will rise with the heat sink. If you add heat sink fins to the heat pipe, you will eventually use fins to dissipate heat. Moreover, the contact points of the fins and the heat pipes are not as good as other methods. The result is a high cost and no improvement in heat dissipation. However, it is useful to use heat pipes on integrated LEDs, but it must be structurally sound! 5. Believe in the nano-radiation materials promoted by some manufacturers. Radiation heat dissipation is negligible in the current temperature of LED lamps at around 50 degrees Celsius. The radiation coatings promoted by the manufacturers have a good radiation effect even if they are advertised, even if they reach the radiation capacity of black body radiation, the heat dissipation proportion is only a few percent. Moreover, the coating itself hinders the heat transfer, which affects the heat dissipation of the convection.
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Second, the LED heat dissipation problem, we will take a look at the LED heat dissipation problem. Method 1. Aluminum heat sink fins This is the most common heat dissipation method. Aluminum heat sink fins are used as part of the outer casing to increase the heat dissipation area. Method 2, the heat-conductive plastic shell uses LED insulation heat-dissipating plastic instead of aluminum alloy to make a heat sink, which can greatly improve the heat radiation capability. Method 3, air hydrodynamics uses the shape of the lamp housing to create convective air, which is the lowest cost way to enhance heat dissipation. Method 4: The liquid bulb is filled with a transparent liquid having a high thermal conductivity into the bulb of the lamp body by using a liquid bulb encapsulation technique. This is the only technology that uses the light-emitting surface of the LED chip to conduct heat and dissipate heat in addition to the principle of reflection. Method 5, the use of the lamp cap in the household type of less power LED lamp, often using the inner space of the lamp cap, part or all of the heating drive circuit is placed. This makes it possible to dissipate heat from a lamp cap having a large metal surface such as a screw cap because the lamp cap is in close contact with the metal electrode of the lamp holder and the power cord. Therefore, a part of the heat can be derived from heat dissipation. Method 6, the insulating heat-dissipating plastic replaces the aluminum alloy insulating heat-dissipating plastic instead of the aluminum alloy to make the heat-dissipating body. The LED-insulated heat-dissipating plastic improves the heat radiation capability by 4-8 times while maintaining the heat-dissipating ability and the aluminum alloy. The LED heat sink made of this heat dissipating material can greatly improve the overall heat dissipation effect. Method 7, heat conduction and heat dissipation integrated high thermal conductivity ceramics The purpose of heat dissipation of the lamp housing is to reduce the operating temperature of the LED chip. Since the expansion coefficient of the LED chip and the commonly used metal heat conduction and heat dissipation material have large expansion coefficients, the LED chip cannot be directly used. Soldering to prevent high and low temperature thermal stress from damaging the LED chip. The latest high thermal conductivity ceramic material, the thermal conductivity is close to aluminum, and the expansion system can be adjusted to synchronize with the LED chip. In this way, heat conduction and heat dissipation can be integrated to reduce the intermediate part of heat conduction.
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Second, the LED heat dissipation problem, we will take a look at the LED heat dissipation problem. Method 1. Aluminum heat sink fins This is the most common heat dissipation method. Aluminum heat sink fins are used as part of the outer casing to increase the heat dissipation area. Method 2, the heat-conductive plastic shell uses LED insulation heat-dissipating plastic instead of aluminum alloy to make a heat sink, which can greatly improve the heat radiation capability. Method 3, air hydrodynamics uses the shape of the lamp housing to create convective air, which is the lowest cost way to enhance heat dissipation. Method 4: The liquid bulb is filled with a transparent liquid having a high thermal conductivity into the bulb of the lamp body by using a liquid bulb encapsulation technique. This is the only technology that uses the light-emitting surface of the LED chip to conduct heat and dissipate heat in addition to the principle of reflection. Method 5, the use of the lamp cap in the household type of less power LED lamp, often using the inner space of the lamp cap, part or all of the heating drive circuit is placed. This makes it possible to dissipate heat from a lamp cap having a large metal surface such as a screw cap because the lamp cap is in close contact with the metal electrode of the lamp holder and the power cord. Therefore, a part of the heat can be derived from heat dissipation. Method 6, the insulating heat-dissipating plastic replaces the aluminum alloy insulating heat-dissipating plastic instead of the aluminum alloy to make the heat-dissipating body. The LED-insulated heat-dissipating plastic improves the heat radiation capability by 4-8 times while maintaining the heat-dissipating ability and the aluminum alloy. The LED heat sink made of this heat dissipating material can greatly improve the overall heat dissipation effect. Method 7, heat conduction and heat dissipation integrated high thermal conductivity ceramics The purpose of heat dissipation of the lamp housing is to reduce the operating temperature of the LED chip. Since the expansion coefficient of the LED chip and the commonly used metal heat conduction and heat dissipation material have large expansion coefficients, the LED chip cannot be directly used. Soldering to prevent high and low temperature thermal stress from damaging the LED chip. The latest high thermal conductivity ceramic material, the thermal conductivity is close to aluminum, and the expansion system can be adjusted to synchronize with the LED chip. In this way, heat conduction and heat dissipation can be integrated to reduce the intermediate part of heat conduction.
Pipe fabrication can be defined as the process of cutting, bevelling, and welding piping components such as pipes, tees, elbows, flanges, reducers, etc., as dictated by the design documents. Various types of plastic tools and equipments are used that helps in process of piping fabrication activities There are three main types of Polyethylene Pipe Fusion Methods: 1.Butt Fusion. Butt fusion is the most common method of fusing HDPE pipes. 2. Electrofusion. Another way to fuse two segments of pipe is electrofusion. 3. Socket Fusion. Socket fusion involves heating the spigot end of one pipe and the socket end of a fitting. So pipe tools of HDPE Fusion Equipments are different. HDPE Pipe Cutter, Inner Debeader, External Debeader, HDPE Pipe Squeezing Tool,Pipe Cutting and Bevelling Equipment etc are used for HDPE/Poly Pipe Butt Fusion Machines; Pipe Scraper and Electrofusion Clamps are used for HDPE Electrofusion Machines. Pipe Depth Gauge, Plastic Pipe Shear and Plastic Pipe Cutters are used for PPR Pipe Socket Fusion Welding Kit. For more Pipe Fabrication tools requirement, you can contact us freely.
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