1. Core design differences
Sealing structure
Elastic seat butterfly valve: The valve seat or butterfly plate is covered with non-metallic materials such as rubber and polytetrafluoroethylene, and the elastic deformation is used to compensate for the deviation of the sealing surface to form a soft sealing effect. In the typical structure, the sealing ring is directly embedded in the valve body or the periphery of the butterfly plate, which is suitable for fluids containing impurities but has limited temperature resistance (-40℃~120℃).
High-performance butterfly valve: Based on metal hard seals (such as stainless steel, chrome-molybdenum steel) and multi-eccentric structures (double eccentric, triple eccentric), line contact or surface contact sealing is achieved through precision machining, and the temperature resistance can reach 550℃ and supports high-pressure working conditions. Some models use spring compensation mechanisms to automatically adjust the sealing gap to adapt to medium pressure fluctuations.
Drive and action characteristics
Elastic seat butterfly valves mostly use a midline structure. When opening and closing, the butterfly plate and the valve seat are in direct contact and friction, and the deformation buffer of the elastic material is required. It is suitable for manual or ordinary pneumatic actuators.
The high-performance butterfly valve uses a three-eccentric design to make the butterfly plate rotate after it leaves the valve seat. There is zero friction during the operation. It can be quickly cut off and flow adjustment with high-precision pneumatic/electric actuators.
2. Comparison of performance and application scenarios
Working adaptability
Elastic seat type:
Applicable to water, air, weakly corrosive media and fluids containing suspended particles, with a nominal pressure of ≤PN16.
Typical scenarios: municipal water supply, sewage treatment, food and pharmaceutical pipelines with high sanitation requirements.
High-performance type:
Resistant to extreme temperatures (-100℃~850℃), high pressure (PN40 and above) and particles and viscous media (such as high-temperature oil, steam, gas).
Typical scenarios: harsh industrial environments such as petrochemical refining, power steam systems, and air separation equipment.
Function and reliability
The elastic seat butterfly valve has excellent sealing performance (leakage level up to VI), but frequent opening and closing can easily lead to rubber aging, and the seals need to be replaced regularly.
High-performance butterfly valves have both regulation and cut-off functions, support bidirectional pressure bearing and fireproof design, have an opening and closing life of more than 100,000 times, and are maintenance-free for a long time.
3. Economic efficiency and selection recommendations
Cost comparison
Elastic seat butterfly valves have low manufacturing costs and are suitable for medium and low pressure scenarios with limited budgets, but the operation and maintenance costs increase with the replacement of seals.
High-performance butterfly valves have high initial investment (30%-50% higher than ordinary butterfly valves), but lower life cycle costs, especially suitable for high wear and high frequency conditions.
Selection principles
Preferably choose elastic seat butterfly valves:
Low cleanliness of the medium (including fibers and particles)
Normal temperature and pressure and frequent opening and closing
High requirements for hygiene or corrosion resistance (such as drinking water pipes).
Preferentially choose high-performance butterfly valves:
High temperature/high pressure/strongly corrosive media
Requires bidirectional sealing or fireproof and explosion-proof design
Precise flow regulation requirements (such as chemical reactor feed control).
Through differentiated innovations in material science and mechanical design, the two cover the fluid control needs of conventional civil and cutting-edge industrial fields respectively.