In order to implement the important instructions put forward by the 20th National Congress of the Communist Party of China to “accelerate the realization of high-level scientific and technological self-reliance and self-reliance” and “resolutely win the battle against key core technologies”. On April 26, China Chemical News Co., Ltd. and China Machinery Maintenance Association Valve Maintenance and Remanufacturing Branch held a forum on the localization and remanufacturing industry of high-end petrochemical valves in Hangzhou. Discussion and exchange on new industrial service models of “replacement” and “high-end valve in-service remanufacturing”. Dr. Qi Huan, Chairman of Huirui, gave a special report as an invited guest. Huirui appeared at the forum as a provider of surface repair and remanufacturing of workpieces in the valve industry.

At the meeting, Dr. Qi Huan delivered a special report on “Research Status and Development Trends of Advanced Surface Engineering and Additive Manufacturing Technology at Home and Abroad”. Dr. Qi Huan used laser metal direct deposition technology as a guide to show everyone the mobile laser cladding equipment, environmental chamber laser additive system, laser cladding components, and intelligent systems independently developed by Huirui, fully demonstrating the metal additive technology Development and Prospects of Manufacturing Technology. In the report, Dr. Qi Huan shared Huirui and the industry’s advanced valve cladding cases, demonstrating Huirui’s mature process technology level. The wonderful report delivered by Dr. Qi Huan was highly recognized by the guests and the audience. Participating business leaders, technicians, and experts from research institutions all said that Huirui’s advanced surface engineering and additive manufacturing technology will inject new vitality into the valve industry and make greater contributions to the localization and remanufacturing of valves.

After the meeting, the guests and company representatives stopped at Huirui’s booth one after another to visit Huirui’s cladding samples in the valve field and watch the video of the valve cladding process. They became very interested in Huirui’s advanced laser cladding process technology. During the heated exchange, the participating representatives also agreed to go to Huirui for further technical discussions and visits.

This forum aims to promote the localization process of petrochemical valves through independent innovation and focus on “dual carbon” valve remanufacturing to lead to green development. It brings together valve business leaders, senior technicians, and experts from research institutions across the country to discuss the localization of high-end valve manufacturing. Conduct in-depth discussions and research on valve remanufacturing technical standards, market structure, and development trends. This has laid a solid foundation for the rapid development of localization of high-end valve manufacturing and valve remanufacturing and promoted the sustainable development of the valve industry.

In recent years, the localization rate of large-scale chemical plants such as large-scale refining and new coal chemicals in my country has increased year by year, and the manufacturing, design, and research and development levels of key components such as valves have continued to improve. However, some key core equipment still relies on foreign imports. In the future, Huirui will use more than ten years of professional experience in laser metal additive manufacturing technology to continue to explore and deepen the field of valve remanufacturing and repair, promote the localization process of high-end valves for the petrochemical industry, help the valve industry chain safely break through bottlenecks, and contribute to the valve industry. The localization of high-end valves contributes to Huirui’s strength.

Application of laser cladding process in the valve industry

Application background

The sealing part of the valve frequently undergoes friction, extrusion, erosion, corrosion, etc. during the opening and closing process. The sealing surface is quickly worn and corroded. Therefore, existing valves basically use seals made of different materials from the valve body in the sealing part. parts to extend the service life of the valve. A common combination is that the valve body is made of ductile iron or cast steel, and the sealing surface is made of copper or stainless steel. The traditional combination method is that the valve body and the seal are connected through threads or interference extrusion. The disadvantage is that there is a risk of leakage at the joint part. The second combination method is to overlay the sealing part on the valve body. The disadvantage is that the welding layer It is loose, has many defects, and has a large heat-affected zone in the matrix. Laser cladding can improve the above two shortcomings.

Advantages of laser cladding compared to traditional process technology

1. Increase service life
Laser-strengthened valves have better resistance to friction, wear, erosion, and corrosion, which reduces production shutdown losses caused by valve-sealing surface accidents and improves the safety and reliability of the production line.

2. Meet working conditions requirements
The cladding layer forms a metallurgical bond with the base material. The cladding layer is uniform and dense, and the structure has no defects such as cracks, pores, unfusion, inclusions, and undercuts.

3. On-site partial repair
For large-diameter pipeline valves, traditional repair welding and surfacing repair methods have large heat-affected zones, causing thermal deformation of the sealing parts; laser cladding technology can directly repair local damaged parts of the valve on the pipeline.

Laser cladding case of desulfurization and denitrification centerline butterfly valve in a factory

1. All exposed surfaces of the butterfly plate must be added, and the sealing surface roughness should reach 0.8;

2. Operating temperature -35℃~135℃, no leakage after opening and closing 45,000 times;

3. The material is ductile iron substrate surface cladding, 2205, 2507, 1.4469, 1.4529, and other duplex stainless steel materials;

4. Common size specifications are DN40-DN1200, cladding thickness: sealing surface 1.5~2mm, other surfaces 0.8~1mm;

5. The cladding layer forms a metallurgical bond with the base material, and the structure is free of defects such as cracks, pores, lack of fusion, inclusions, and undercuts.