Hello, I am Shenzhen Chenmei Pigment Masterbatch Co., Ltd., engaged in the production of masterbatch, toner and other pigments. I have a certain understanding of pps. The following is my answer:
Electronic and electrical: Micro electronic component packaging, connectors, connectors, sockets, coil bobbins, trimmer capacitors, and fuse bases.
Mechanical instruments: pump casing, pump impeller, tiles, gears, pulleys, universal heads, seals, flanges, counters, levels, flow meter components.
Automotive field: temperature sensor, carburetor, evolver, carburetion pump, seat base, water tank water chamber.
Household appliances: electric fans, microwave oven stands, clothes dryers, coffee cookers, rice cookers, hot air cylinders, hair irons, air conditioning compressors.
Military field: production of fighter aircraft, missile vertical tails, missile combustion chambers, aviation, aerospace, aircraft connectors, coil frames, instrument panels, and many other components, especially the main components of stealth fighters and bombers. Nuclear radiation-resistant parts of nuclear submarines, guns, helmets, military tents, utensils, astronaut supplies, corrosion-resistant and wear-resistant parts of warships and submarines, new combat vehicles developed by the United States (in the production stage) and plastic tanks developed by the United Kingdom ( In experimental phase) etc….
Fibers and films: PPS fibers are blended with other synthetic fibers to make high-performance industrial filter cloths and radiation-resistant aerospace cloths. PPS film is the best insulating material reaching Class F. It can be used to make capacitors, impedance electronic components, flat coil bobbins, wire coverings, covers, vaporizer diaphragms, thermal printing materials, flexible disks, photosensitive tapes for electronic photography, etc. .
The working principle and purpose of the cooling tower
The function and working process of the cooling tower
Let’s talk about the function of the cooling tower , we need to talk about the workflow of thermal power plants first.
After the fuel is sent to the power plant, it is filtered and transported to the boiler for combustion. After the boiler is heated, the water in the boiler turns into high-temperature steam. The water vapor is transported to the steam turbine through the pipeline, pushing the steam turbine to rotate and produce work. The generator and the steam turbine are connected through a coupling, thereby driving the generator to generate electricity. The water vapor that has done work through the steam turbine is sent to the condenser, where it is cooled by the cooling water and condensed into water. Part of it is pressurized and transported to nearby communities for heating. Thermal power plants require large amounts of cooling water to cool down the units. The cooling tower provides cooling water for this purpose.
Power plant workflow
Thermal power plant workflow
The bottom diameter of the cooling tower is generally 65 to 120 meters, and the height is 75 to 150 meters. It consists of three parts, namely the lower ring beam, the cylinder wall, and the tower top rigid ring. The lower beam ring is at the lower part of the air duct, and all loads are transferred to the diagonal support through the lower beam ring. The cylinder wall is the main part of the cooling tower, and its shape and wall thickness are determined through optimization calculations. The rigid ring at the top of the tower is the reinforcing hoop of the cylinder shell. There is a collection tank about 2 meters deep at the bottom of the tower. on the tube wallThe lower part is equipped with water distribution tank and sprinkler device.
The working process of the hyperbolic cooling tower
The cooling tower body is relatively high and is easy to form a smoke window effect(Smoke window effect: indoor air moves along a space with a vertical slope Rise or fall, causing the air to strengthen convection. When the chimney becomes narrower, the air flow will accelerate. Due to the difference in air pressure between the upper and lower air, wind will flow from the bottom of the tower into the top of the tower. The hot water from the condenser is transported to the water distribution tank in the middle of the cooling tower, where it is sprayed into droplets. As the water droplets fall, cold air rises, cooling the hot water in the process. The rising water vapor emerges from the upper mouth, which is the white mist we see. The cooling water falls into the water collection tank and is re-transported to the condenser for recycling.
Why is it hyperbolic?
Structurally speaking, the hyperbolic structure is stronger. Here, we will first talk about the Bernoulli effect, which is the boundary layer surface effect. The scientist Bernoulli has verified through countless experiments and concluded that where the fluid velocity is high, the pressure is low, and where the fluid velocity is low, the pressure is low. powerful. For example, when we are waiting for the train, we have to stand outside the yellow line. Because the closer to the train, the velocity of the gas is greater, while the flow velocity farther away is smaller, which creates a pressure difference. If it is too close, it may be sucked away by the train. Let’s talk about the hyperbolic structure again, because the air flow rate near the cylinder wall is slower than the center, which will produce an inward pulling force. In this way, the barrel body is easily damaged. And curved structures can add structure and strength.
Hyboloid structures are easier to build from an economic perspective. A hyperboloid is actually a ruled surface that is formed by continuous linear motion. Taking advantage of this property, hyperboloid structures can be constructed using only straight beams, which are easier to construct.
Hyperboloid
Cooling tower construction
Effectively, the hyperbolic shape makes it easier to circulate air. The bottom diameter is the largest, allowing maximum cold air to enter. When reaching the smallest part, because the pipe diameter becomes smaller, the air flow speed accelerates, which can take away the heat as quickly as possible. After reaching the top, the diameter of the pipe becomes larger, and the pressure of a large amount of hot gas decreases here, releasing the heat and forming white water vapor.
Basic Principles of Working of Cooling Towers A direct, or open circuit, cooling tower is a means of sealing the interior of the structure by spraying circulating water through the fiberglass fill. superior. The filler provides a larger contact surface and achieves heat exchange through the contact between water and air. Then a fan drives the air flow in the tower to circulate, taking out the hot air flow after exchanging heat with the water, thereby achieving cooling.
Infill may consist of multiple, primarily vertical, wet surfaces over which water spreads (infill) or lateral splash elements creating several layered films that cascade into many small water droplets over a larger surface area(splash).
Indirect or closed circuit cooling towers do not involve direct contact between air and a liquid, usually water or a glycol mixture being cooled. Unlike open cooling towers, indirect cooling towers have two independent fluid circuits. One is an external circuit in which the water is circulated in a second circuit, which is the outer loop of the tube bundle (non-open coil) connected to the hot fluid process to be cooled and returned in a closed circuit.
Air is circulated through cascading water drawn outside the entire heat pipe, providing evaporative cooling similar to an open cooling tower. In operation the heat flows from the internal fluid circuit, through the coil tube walls, to the external circuit and then to the atmosphere, heated by some evaporation of air and water.
The action of an indirect cooling tower is therefore very similar to that of an open cooling tower with one exception. This process cools the liquid in a "closed" circuit and is not directly exposed to the atmosphere or external circulating water.
As air in a counterflow cooling tower moves upward through the fill or tube bundle, the opposing water moves downward. In a cross-flow cooling tower as air moves horizontally through the fill, water moves downward.
Cooling tower uses: Mainly used in air conditioning cooling systems, refrigeration series, injection molding, tanning, foaming, power generation, steam turbines, aluminum profile processing, air compressors, industrial water cooling and other fields, with the most applications For air conditioning cooling, refrigeration, plastic chemical industry.
Extended information
Application scope of cooling tower:
Waste heat generated during industrial production or refrigeration process is generally used Cooling water is directed away. The function of the cooling tower is to exchange heat between the cooling water carrying waste heat and the air in the tower, so that the waste heat is transferred to the air and dispersed into the atmosphere.
For example: In a thermal power plant, the boiler heats water into high-temperature and high-pressure steam, which drives the steam turbine to do work to make the generator generate electricity. The waste steam after the work of the steam turbine is discharged into the condenser, where it exchanges heat with the cooling water and condenses. The water is then pumped back to the boiler for recycling.
In this process, the waste heat of the exhaust steam is transferred to the cooling water, causing the water temperature to rise. The cooling water carrying the waste heat transfers heat to the air in the cooling tower and is discharged from the air duct. in atmospheric environment.
Baidu Encyclopedia-Cooling Tower