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We have many ways to classify ball valves. When it comes to the body style, ball valves can often be divided into side entry ball valve, top entry ball valve and fully welded ball valve. In this article, we will discuss about the differences among these three types. Side entry ball valves are the most common type we use in different industries. The valve is assembled from sides through bolts and n...
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(1) Soft sealing material A. Nitrile rubber (NBR). Nitrile rubber has excellent oil resistance; heat resistance is superior to natural rubber and styrene-butadiene rubber; air tightness and water resistance are better. Nitrile rubber can be divided into butyronitrile-18, butyronitrile-26 and butyronitrile-40. Nitrile rubber is suitable for petroleum products with a temperature of -60 ° C ~ +120 ° ...
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Before we select an appropriate ball valve, there are many factors we need to take into consideration. Seat type is one of important perspectives. Soft Seated Ball Valve The seat ring in contact with the ball part is made of soft material, such as PTFE, RPTFE, Nylon, Devlon, Peek and so on. For floating ball valve, there is only one soft seat ring for one side seat. But for trunnion ball valve, th...
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The factors affecting the sealing performance of the c are as below: A. sealing surface quality; b. sealing surface width; c. pressure difference; d. sealing surface material and its processing state; e. medium properties; f. surface hydrophilicity; g. the existence of sealing oil film ; h. the solid and structural characteristics of the closure. 1) Influence of sealing surface quality on valve se...
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Most of ball valves own the sealant injection system. In this article, we will explain why ball valve is installed with sealant injection fittings. Generally speaking, each ball valve has two sealant injection fittings. One is located at the stem area and the other seat area, like the picture shown below. The sealant injection system of ball valve plays a part as the emergency sealing or backup se...
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3. The influence of pressure difference before and after valve on sealing performance Theoretically, the pre- and post-valve pressure difference and leakage are proportional. However, the test proved that, under the same conditions, the increase in leakage is more than the increase in pressure difference. 4. The influence of sealing surface material and its treatment state on sealing performance T...
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