Heat exchangers have played their unique role in heat exchange in household air conditioners, multi-connections, central air conditioners, cold storage and other products, and have become a topic of common concern in the industry.
Effectiveness, energy saving, and environmental protection have become the mainstream trend of the whole machine market. Based on the existing heat exchanger products, the future development of the heat exchanger will follow the development trend of the whole machine. What technological breakthroughs and market breakthroughs are ushered in?
According to statistics, in the modern chemical industry, the investment of heat exchanger equipment manufacturers accounts for about 40% of the total equipment investment, and it accounts for about 47% of all process equipment in the refinery. Almost all seawater desalination process devices are replaced by Heater. A survey of foreign heat exchanger markets shows that although the competitiveness of various plate heat exchangers is increasing, tube and shell heat exchangers still dominate about 74%.
In recent years, with the rapid development of petrochemical, steel and other industries, the demand level of heat exchangers has risen sharply, but the limited supply capacity of domestic enterprises has led to a market situation where the heat exchanger industry is in short supply. Imports are needed to make up for the huge supply gap . A heat exchanger is a device that transfers the heat of a higher temperature fluid to a lower temperature fluid in a certain heat transfer manner. Among them, at least two fluids with different temperatures participate in the heat transfer. The fluid with a higher temperature emits heat, and the fluid with a lower temperature absorbs heat.
It is widely used in energy and power, refrigeration, chemical, metallurgy, petroleum and other industries. It is an indispensable and important part in various production fields. For example, superheaters, economizers, air preheaters, high-pressure heaters and low-pressure heaters, deaerators, and cold water towers of boiler equipment in the process of thermal power; in the modern petrochemical industry, the investment of heat exchangers is even more It accounts for 30% to 40% of the total investment. In addition, according to China's basic energy policy of "giving equal priority to energy development and conservation, and putting energy conservation first", based on the fundamental approach of "saving first, efficiency first", the application of heat exchangers is closely linked to development and energy conservation.
The heat exchanger synthetic rubber can change its shape like a fluid. Of course, it cannot flow. When the compression force that compresses the deformation disappears, it can return to its original shape. It should have sufficient strength to withstand the deformation. It enters the squeeze force of the sealed state and withstands high pressure fluid media.
The heat exchanger adjusts the formula so that it can not only achieve sufficient strength suitable for use, but also sufficient plasticity, so that it can closely adhere to the metal surface under appropriate pressure, thereby producing a sealing function. The polymer three-dimensional network structure of synthetic rubber in the heat exchanger can resist the penetration of any different chemical quality liquids. The rubber in polymer materials has a disadvantage, which is that all synthetic rubber materials can only be resistant to temperature. Suitable for a relatively narrow temperature range, so it is very important to carefully choose the material formula according to the temperature required for use.
Many new synthetic materials have a longer service life compared to the old models. This is due to the use of new additives to extend the service life. In this regard, it is very important for the heat exchanger to properly choose a synthetic material formula. All rubber-based synthetic materials will experience stress relaxation. During the use process, due to chemical changes inside the synthetic material, the initial sealing function will gradually decline, and when When the sealing performance is below a relatively low limit, leakage will inevitably occur.
According to the specific structural conditions of the heat exchanger, the relative sizes of the components, and the dangerous working conditions, the relatively large values of the stresses of the tube sheet, tube, or shell may all exceed the respective strong (rigidity) check conditions first. Therefore, when designing the heat exchanger, whether it is a tube sheet, tube or shell, the relatively large stress value that may occur from each dangerous working condition should be obtained and verified to meet the requirements. It cannot be verified with a stress value that is not relatively large. Not to mention that the strength of the pipe or shell can not be considered as a problem because the stress of the pipe or shell can be lower, or even not calculated.
In the cleaning of heat exchangers, no matter they are mechanical methods, high-pressure water methods, or chemical methods, these are not optimal. They all have such problems. For example:
1. The scale inside the heat exchanger cannot be thoroughly cleaned;
2. The sediment inside the heat exchanger cannot be completely eliminated;
3. Chemical cleaning will cause corrosion to the heat exchanger equipment; and if these chemical solvents are not removed, the remaining materials will cause secondary corrosion to the equipment, and in severe cases, the equipment will be scrapped;
4. In addition, the waste cleaning liquid contains a lot of bad substances, and its discharge will definitely cause pollution to the environment.
At present, the market has developed and produced cleaning agents that are non-corrosive to heat exchangers and that are safe and environmentally friendly. Due to the special ingredients added to this cleaning agent, it can effectively remove scale during use, and it will not have any impact on the heat exchanger. It can ensure the life of the heat exchanger. It is important that No emissions are safe for humans and the environment.