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Spiral plate heat exchangers feature a special spiral structure; thanks to the effect of the centrifugal force generated by the spiral flow and the impact force from the spacing columns, the fluid can more easily reach a turbulent state, resulting in better thermal efficiency. Additionally, they are compact in size, and are widely used in various industrial sectors such as chemicals, pharmaceuticals, petroleum, and power generation. However, various cracks occur during the welding process. Welding cracks not only pose many difficulties in production but can also lead to catastrophic accidents. According to statistics, among the accidents involving welded structures worldwide, aside from a few cases caused by improper design or unsuitable material selection, the vast majority are failure incidents resulting from welding cracks. It is crucial for spiral plate heat exchangers to provide timely protection once welds appear. Leakage issues occurred at the middle section of the mother liquor feed ends of two spiral plate heat exchangers in a petrochemical company. Since the entire production facility had just been put back into operation following maintenance, and to avoid shutdowns, it was necessary to shut down the heat exchangers and reduce their load in order to keep the facility running. The heat exchanger is made of 316L material; its plate width is 1799 mm, outer diameter is 1700 mm, and overall length is 2766 mm. There is leakage at the middle of the feed end, caused by cracks. To address the aforementioned issues, the manufacturer provided two solutions: (1) TIG welding to repair the leaking areas ； (2) Use Sorey carbon nanopolymer material for leak protection. However, during the actual repair process, it was found that the leakage site in the equipment was too small for TIG welding to be carried out; therefore, it was decided to use Sorex carbon nanopolymer material for the repair. The specific repair steps are as follows: 1. Go to the site, take safety measures and make necessary preparations, and select the appropriate materials and tools based on the condition of the equipment ； 2. Drain all the medium from the spiral plate heat exchanger and identify the location of the leak ； 3. Clean the equipment surface: Use a brush and high-pressure water to remove the scale layer from the metal surface ； 4. Use a 60# sanding belt or power tool to grind the leaking areas of the heat exchanger; after grinding, the metal surface should be rough, clean, free of rust or dirt ； 5. Clean the repair area with anhydrous ethanol until it is clean and dry ； 6. Apply the mixed SD8002D material to the leaking area and wait for it to cure ； 7. After curing, check for any minor leaks; ensure that all leaks have been sealed and verify the effectiveness of the repairs. When using Sorey material for repairs, there is no need to worry about thermal stress; it does not alter the properties of the metal, nor does it cause cracks in the welds of heat exchangers. This is because the material utilizes its adhesive properties for repair, and it boasts excellent comprehensive properties such as high temperature resistance, corrosion resistance, and resistance to strong acids and alkalis. It has advantages such as a convenient repair process, no dependence on environmental conditions, no need for specialized equipment or instruments, ease of use, and low repair costs. During future regular maintenance, protection can also be achieved by using Sorex carbon nanopolymer materials ； Even if leakage occurs later on, it can be repaired promptly using the Sorex technology, preventing prolonged surfacing repairs from disrupting production. It is precisely this level of meticulous management that **reduces the likelihood of leakage problems in heat exchangers**. It not only lowers the costs associated with purchasing such equipment, but also ensures product quality and production efficiency, thereby enhancing the competitiveness of the products.