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Comparison of advantages and disadvantages of ball valve and butterfly valve
First, from the aspect of circulation capacity, the ball valve's circulation capacity is better than the butterfly valve, because the butterfly valve in the middle of the open state, the valve plate and the valve shaft occupy a part of the flow channel, the smaller the caliber they occupy the larger the proportion of the circulation channel.
Second, from the use of temperature, due to the sealing material and structure of the ball valve is not suitable for steam medium, and the butterfly valve can be used for conventional heating with saturated steam medium (350 degrees below).
Third, from the standpoint of the pipe network stress, due to the valve structure, the butterfly valve can withstand higher stress.
Fourth, from the service life point of view, the ball valve and butterfly valve can achieve a longer life (normal use for more than 15 years), but the non-metallic ball valve plays an important role in the sealing structure, while the butterfly valve is a pure metal to metal seal, Therefore, the life of the butterfly valve will generally be longer.
Fifth, from the operating torque, because the butterfly valve for the three eccentric metal seal butterfly valve, so the butterfly valve opening and closing torque is very small, and the ball valve with the increase of the diameter of the sealing surface contact area will also increase with it, random Large-diameter ball valves can have very large opening and closing moments.
Sixth, from the point of view of volume and weight, that is, ease of installation, valves below DN300 are better, and valves above DN300 are smaller and lighter.
Seven, from the sealing performance point of view, the ball valve sealing performance is better than the butterfly valve, ball valve for the two-way zero leakage. The butterfly valve is a two-way ANSI Class V standard (no visible leakage). Therefore, both are sufficient to meet the needs of the heating pipe network and will not affect the normal maintenance and repair of the pipe network.
Eight, from the price point of view, DN250 (inclusive) below the ball valve price will be better, DN300 above the diameter of the butterfly valve will have more advantages.
To sum up, in the centralized heating general pipe network, the ball valve below the DN300 diameter is more cost effective, and the butterfly valve above the DN300 diameter is more cost-effective. This is also the choice of many years of design and user experience.