Silicon carbide nozzles are a new type of ceramic material characterized by high-temperature resistance, oxidation resistance, high strength, resistance to extreme cold and heat, excellent thermal shock resistance, minimal high-temperature deformation, good thermal conductivity, wear resistance, and corrosion resistance. So, how much do you know about the structure of silicon carbide nozzles? Different structures of silicon carbide result in variations in processing efficiency and nozzle lifespan. A reasonable nozzle structure is essential for achieving high abrasive velocity, thereby improving processing efficiency and reducing costs. From the inception of nozzles until a long period afterward, cylindrical nozzle structures were predominantly used. To date, a variety of nozzle structural forms have been developed both domestically and internationally. 1. Cylindrical Straight-Hole Nozzle Structure The cylindrical straight-hole silicon carbide nozzle combines the functions of both a spray gun and a nozzle. It has a simple structure and can be directly replaced with seamless steel tubes or obtained by drilling holes in materials. However, its lifespan is relatively short, and it is mostly used in applications where sandblasting requirements are not stringent. 2. Tapered Nozzle Structure This nozzle structure features a conical inlet for flow guidance and a straight section for focusing. Abrasives enter the nozzle more easily, and the distribution of abrasives across the nozzle cross-section is more uniform compared to cylindrical nozzles. 3. Venturi Nozzle Structure The Venturi nozzle structure consists of a Venturi-shaped throat and a slightly conical outlet with a slightly larger diameter. The airflow reaches sonic speed in the throat section and can achieve supersonic speeds exceeding 355 m/s at the nozzle outlet (whereas the exit velocity of abrasives in a typical cylindrical straight-hole nozzle is low, only about 97 m/s). This nozzle is primarily used to achieve very high abrasive velocities, improving cleaning efficiency by 15%-25% compared to ordinary nozzles. To prevent rapid wear, the nozzle liner can be made of hard alloys or ceramic materials. To avoid clogging, the nozzle diameter should be 3-4 times the size of the abrasive particles. 4. Special Nozzles Special sandblasting nozzles have complex structures and are generally used in specific applications, such as sandblasting the inner walls of pipelines. 5. Combined Nozzle Structure Materials with different properties are designed for the inlet, outlet, and middle sections of the nozzle, and these parts are assembled mechanically to form the nozzle. In the combined nozzle, the inlet and outlet sections are designed with high-hardness ceramics or other wear-resistant materials, while the middle section can be designed with high-toughness metals or other materials. The combined nozzle meets the varying requirements for erosion and wear resistance at different sections, thereby enhancing the nozzle's overall resistance to erosion and wear to some extent. However, compared to monolithic nozzles, it requires the preparation of two or more materials and involves additional processes such as assembly.