1. The structure features
There are obvious differences between the category A butterfly valve and category B butterfly valve in structure.
1.1 Category A butterfly valves are "concentric" type, it usually has a simple structure, consisting of the valve body, valve disk, valve seat, valve shaft and a transmission device. The valve disc is disc-shaped and rotates around the valve shaft to control the flowing of fluid.
1.2 In contrast, category B butterfly valves are “offset” type, meaning the shaft is offset from the disc, they are more complex and may contain additional seals, supports, or other functional components to provide greater sealing performance and stability.
2. Applications in different working conditions
Due to the differences in structure, category A butterfly valve and category B butterfly valve are also applied in different working conditions.
2.1 Category A butterfly valves are widely used in low pressure, large diameter pipeline system, such as drainage, ventilation and other industries, because of its simple structure, small size, light weight and other features.
2.2 Category B butterfly valve is more suitable for the working application with high sealing performance requirements and large medium pressure, such as chemical, petrol, natural gas and other industries.
3. Performance advantage comparison
3.1 Sealing performance: category B butterfly valves are generally better than category A butterfly valves in sealing performance, thanks to their more complex structure and additional seal design. This enables the category B butterfly valve to maintain a good sealing effect in harsh environments such as high pressure and high temperature.
3.2 Flow capacity: The flow capacity of category A butterfly valve is strong, because the valve disk design is relatively simple, the resistance of fluid passing is small. The category B butterfly valve may affect the flow efficiency of the fluid to a certain extent due to its complex structure.
3.3 Durability: The durability of category B butterfly valves is usually higher, because its structural design and material selection pay more attention to long-term stability and corrosion resistance. Although the category A butterfly valve is simple in structure, it may be more vulnerable to destroy in some harsh environments.
4. Purchasing precautions
When purchasing category A and category B butterfly valves, the following factors need to be considered:
4.1 Working conditions: Select the appropriate category of butterfly valve according to their working pressure, temperature, medium and other conditions of the pipeline system. For example, category B butterfly valves should be given priority in high pressure and high temperature environments.
4.2 Operation requirements: Clear operation requirements, such as required for quick opening and closing, frequent operation etc., to select the suitable butterfly valve structure and transmission mode.
4.3 Economy: Under the premise of meeting the requirements of operation, consider the economy of the butterfly valve, including purchase costs, maintenance costs, etc., category A butterfly valves are usually lower in price, while category B butterfly valves, although better in performance, may also be relatively high in price.