Let's take a look at the brief introduction of chemical anti-corrosion equipment!
1. Causes of equipment corrosion
Both metal and alloy materials are prone to corrosion problems. Some are caused by human factors and some are caused by natural causes. Natural causes are inevitable, but human factors can be avoided. Generally, the condition that can cause metal corrosion is contact with external medium, which is related to gas and liquid medium.
At present, many chemical enterprises have many problems, but for their equipment, corrosion is always a big hidden danger.
Corrosion occurs on the metal surface, which is really shown by a large number of spots evenly distributed on the surface. Moreover, over time, the thickness of the equipment will be reduced, and some will form a large pit, causing parts to be perforated. Some are invisible, and the specific location is between metal grains. When the corrosion reaches a certain degree, the metal can not bear it completely, and it will collapse, which is particularly dangerous. Corrosion will also weaken the metal properties, especially the ductility of the metal. These mechanical properties generally decrease at a slow speed, which we will not notice at all.
Corrosion is a very destructive process for materials. The degree of metal corrosion is determined by many specific factors, such as metal nature, medium properties, operating conditions, etc. Generally speaking, the rise of temperature and pressure is the key factor affecting metal corrosion.
2. Hazards of chemical equipment corrosion
General chemical equipment is easy to corrode. For the research of chemical equipment, the problem of corrosion should be considered from the beginning of its design stage, otherwise it will cause great difficulties for future equipment construction. At the same time, the chemical equipment is also vulnerable to the corrosion of chemical raw materials during operation, which affects some mechanical properties, other functions and performance of the equipment.
If there are loopholes in the design scheme, it will be difficult to solve them again. Usually, the design unit will make mistakes in the work, resulting in defects in the design scheme. In order to put the equipment into use as soon as possible, the designer will reduce the design standard of chemical equipment, which will reduce the corrosion resistance of chemical equipment. This has a great impact on the life of the equipment, virtually also brings a great burden to the production cost, and has a negative impact on labor productivity.
3 Anticorrosion problems in chemical equipment design
The common types of electrochemical corrosion in chemical equipment include pitting corrosion, crevice corrosion, galvanic corrosion, intergranular corrosion, stress corrosion cracking, etc.
3.1 Structural design
During the design of chemical equipment, the designer did not accurately estimate the corrosion resistance of the designed products or did not know enough about the corrosion resistance of chemical products, which caused many problems in the equipment structure in the design results, leading to unreasonable structural design, causing or aggravating corrosion.
Therefore, the structure of chemical equipment is the key factor affecting corrosion. When many units are designing, they are trying to solve the problem of convenient use of the equipment. Their design purpose and design focus directly turn to the installation point of view. As a result, there are many problems in the design scheme, which will also lead to hidden dangers and vulnerabilities. There will be a lot of residual liquid or solid residues in the gaps and dead corners of the equipment, which is the root of the problem. The equipment needs to work for a long time because of the endless liquid discharge. If these substances are not treated accordingly, local liquid will be enriched or enriched, causing corrosion. In order to effectively prevent the occurrence of such problems, we must take some practical measures and means, and follow the principle of eliminating cracks as much as possible and avoiding cracks corrosion when designing structures. Make a choice between the design scheme and the installation scheme, consider which situation is closer to reality and more practical, and choose which solution. The first problem to be solved is the quality and performance of the product. On this basis, the installation and use of equipment should be fully considered.
3.2 Medium analysis
In the early stage of chemical equipment design, the composition, concentration and temperature of solution, gas, steam and other media should be analyzed in detail. If the designer of the pressure vessel does not know the nature of the medium, then it is difficult for the manufacturer or department to make a decision on its quality and corrosion resistance. At the same time, different choices should be made for the content of different media and the reaction between chemical substances. In addition, the content of mixed acid, mixed liquid and impurities, as well as the corrosion and wear of containers and equipment caused by solids mixed in liquid, should be understood in advance as much as possible. For the specific chemical reaction in the equipment, a special corrosion analysis is carried out to thoroughly consider each corrosion factor, and some effective solutions are proposed. The reasonable structure design should also be adopted to effectively avoid the vessel wall thinning caused by cavitation, flashing, scouring, abrasion, abrasion and other reasons, and reduce the probability of hidden trouble.
The corrosion prevention of chemical equipment is indeed a very difficult problem to solve in the chemical industry, which is complex and multifaceted. In the current market economy, some inevitable problems will also arise in the design of chemical equipment. If these problems cannot be solved in time, they will cause considerable losses to production and costs, and even become the fundamental factor leading to serious accidents. Among many chemical production problems, the corrosion problem of equipment is undoubtedly The key problem is the first problem to be solved, which needs to be arranged in detail and designed according to the actual situation. Relevant designers should also raise enough awareness, closely link with reality, and pay attention to it in a timely manner.
The above is a brief overview of anti-corrosion of chemical equipment. I believe you have a certain understanding of this. If you have any other questions, you are welcome to consult.
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