Why were combined sealing rings developed?

Composite sealing rings were developed to combine the advantages of different materials, while overcoming the shortcomings of using a single material in terms of cost, processing, or performance. The following explains why this design was chosen: 1. Material property requirements: The sealing ring must withstand harsh conditions such as high pressure, high temperature, and corrosion during operation, and it is required to have high hardness and wear resistance. Cemented carbide materials such as tungsten carbide perform exceptionally well in these areas. 2. Cost considerations: Although hard alloys such as tungsten carbide have excellent properties, they are expensive and not suitable for large-scale or cost-sensitive applications. To reduce costs, cemented carbide can be used only in the critical parts of the sealing ring, namely the sealing end face. 3. Machining difficulty: Materials such as cemented carbide are difficult to machine, and they also require sophisticated machining equipment, which increases manufacturing costs and technical challenges. To simplify manufacturing, complex parts can be designed to be made from materials that are easier to work with. 4. Design flexibility: By combining different materials, sealing rings can be customized to meet specific application requirements; for example, different materials can be used in various areas to achieve an optimal balance between performance and cost. 5. Connection method: Considering the issue of connecting the cemented carbide to the ring seat, various solutions have been developed. For example: – Hot-fit type: By utilizing the principle of thermal expansion and contraction, the hard alloy ring that expands when heated is inserted into a pre-made ring seat; upon cooling, a tight fit is achieved. - Sealed type: An elastic or plastic seal ring is used to ensure sealing between the cemented carbide ring and the ring seat. - Welding and brazing: The cemented carbide ring is fixedly connected to the ring seat using welding or brazing techniques; this method is suitable for environments subject to high temperatures and pressures. In summary, the design of composite sealing rings is aimed at addressing the issues of high cost and difficulty in processing pure cemented carbide materials. It ensures that the sealing rings exhibit excellent performance in critical areas, while using materials that are less expensive and easier to process in other areas, thereby reducing overall costs and improving production efficiency. The materials and design are optimized to meet the requirements of different application environments. .