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I’ve already searched, and there are no duplicate posts; if any exist, please have the moderators remove them. Chemical process pumps refer to the various types of pumps used in chemical production processes. There are a great variety of chemical process pumps, which can be classified into vane pumps, positive displacement pumps, rotary pumps, etc., based on their working principles. Based on the production process or product characteristics, they can be classified into high-pressure methamine pumps, cryogenic pumps, phosphate slurry pumps, etc. In recent years, with economic development, the variety of chemical products has increased, which has led to new requirements regarding the performance and quality of pump products. In the pump industry, Harbin Pump Factory was the first to introduce the liquefied petroleum pump production technology from the Japanese company Ebara. Subsequently, companies such as Haibogerman Mechanical Seal Company and Shenyang Pizhu Seal Company also brought in advanced manufacturing processes and product production technologies from countries like Germany, the United States, and Australia, thereby solving the problems of leakage in chemical equipment and gaining popularity among users. Phosphoric acid slurry pumps have been largely localized in production. The media that need to be transported during phosphate fertilizer production include phosphorus ore slurry, phosphoric acid slurry, various filtrates, concentrated and dilute phosphoric acids, concentrated and dilute sulfuric acids, as well as fluorosilicic acid; pumps are highly susceptible to corrosion by these media, or to both corrosion and abrasive wear. Phosphoric acid slurry pumps are a general term for various pumps used in the production of phosphate fertilizers; they represent a type of pump that is highly resistant to corrosion and wear. In the early stages of the development of the phosphate fertilizer industry, the chemical corrosion-resistant pumps that were commonly used had a lifespan of only one week. As a result, experts in the pump industry both domestically and internationally conducted extensive research and development work on aspects such as the structural design of phosphate slurry pumps, material testing, and seal technology. In the design of phosphate slurry pumps, the first issue to address is corrosion resistance, or the combination of corrosion and erosion wear. Therefore, special consideration should be given to the structural design as well as the fit between the pump casing and the impeller. The metal materials used for phosphate slurry pumps abroad are selected from different series depending on the properties of the medium. Domestic manufacturers and research institutions have also conducted studies on the corrosion resistance and wear resistance of various materials, developing their own series of materials such as ferritic stainless steels, duplex steels, and austenitic stainless steels. There are many specialized manufacturers of phosphate slurry pumps in China, and institutions such as the Chinese Academy of Sciences, universities, design institutes, and research centers are also involved in research and development. The issue of local production of phosphate slurry pumps has now been largely resolved. Among the large, medium, and small phosphorus compound fertilizer production facilities that have been built in the country to date, large and medium-sized facilities are equipped with approximately 30–40 various types of slurry pumps, while medium and small-sized facilities have around 20–30 such pumps. Assuming an average service life of 6 months per pump, there is considerable market potential. In addition, there are still some large phosphate fertilizer manufacturers in the country whose facilities have just been built or whose construction is still in progress. Coupled with a number of medium and small-scale projects for the renovation and expansion of phosphate ammonium plants, this creates a broad market opportunity for pumps used in phosphate fertilizer production in China. High-pressure methamine pumps rely mainly on imports. High-pressure methamine pumps and high-pressure liquid ammonia pumps are the types of pumps in urea plants that are subject to severe corrosion and represent the greatest technical challenges. Reciprocating piston structures are commonly used in medium and small urea plants, while multi-stage centrifugal and high-speed partial-flow types are often used in large urea plants. In recent years, reciprocating piston structure pumps have also emerged. Reciprocating pump units are large in size, complex in structure, and difficult to maintain; their pump bodies are prone to fatigue cracking, but they operate reliably and with high efficiency. High-speed partial-flow pumps use two-stage radial impellers, with rotation speeds of over 14,000 revolutions per minute. They have a compact design and operate smoothly, but issues related to sealing and wear are quite prominent and difficult to resolve. Multi-stage centrifugal pumps fall between the two; they are relatively easier to manufacture, have a better sealing structure, and are more reliable. High-pressure methylamine pumps of these three structural types have been developed in China, and there are no major issues regarding their manufacturing and operational reliability; however, at present these products are still mainly imported. Domestic products have competitive advantages. It is understood that for the three main categories of equipment used in China’s chemical industry – pumps, fans, and valves – over 85% are domestically produced, with only a small portion being imported. The main reason for importing is that domestic products cannot meet the technical requirements; as long as domestic products can satisfy these requirements, they remain the users’ first choice ； Secondly, the batch sizes are insufficient; most are single units, developed from scratch in China, which is not profitable. There are also some users who are unaware of or hold prejudices against domestic equipment; they fail to conduct a thorough analysis and subjectively assume that foreign equipment is more advanced and reliable, leading to blind adoption of such equipment. This represents an unnecessary obstacle in the process of localizing equipment production. Apart from these special reasons, chemical companies mainly rely on the domestic market when purchasing products. Since domestic equipment has a significant price advantage, especially in terms of the cost of spare parts and the timeliness of service, it offers a stronger competitive edge over foreign-made equipment; therefore, the cost-performance ratio becomes the main factor that determines whether users choose imported or domestic equipment. Generally, the price of domestic pump equipment is only 50% of that of similar imported equipment, while the price difference for spare parts is even greater. The biggest drawbacks of imported products are the difficulty in obtaining replacement parts and their high cost. As long as the products don’t break, it’s fine; but once they do, it can cause the entire production line of the company to come to a halt. Users prefer products that are of high quality at affordable prices. The equipment selected by Guangdong Jiantao Chemical Company and Guangdong Rongtai Group, two major chemical enterprises, covers all types of corrosion-resistant pumps, making them representative of the chemical industry. To this end, the author conducted a survey on the main factors they consider when selecting pump equipment. According to surveys, chemical companies currently do not use open bidding when purchasing pump products; instead, they employ a comparison approach, and sometimes even invite designers and manufacturers for face-to-face technical discussions, with the end user deciding which company’s product to buy. In addition, the chemical industry considers quality as the primary factor when purchasing products, price as the secondary factor, and after-sales service as the third factor.