双关双断旋塞阀 说明书.pdf.pdf

www.3ZV TWIN SLIP PLUG VALVE Double Block Bleed Critical Drop Tight Sealing For use in oil, Refined Products Petrochemical Application Table of Contents Page *Design 3 *Operation 4 *DTR Bleed System 5 *Exploded View 6 *Standards 7 *Cv Torque Data 8 *Bleed System 9,10,11 *Application 12 *Operator Locking Devices 14 *Dimension 15,16,17 *How to Order 18 2 Design Features ● Zero Leakage Valve selection is very important in the petroleum industry. An incorrect valve selection causes the decrease of income, the pollution of product, and the increase of product line maintenance cost., Multi product system valves should be designed to withstand frequent cycling and drop tight seal shut off up stream and down as required. The double block and bleed was developed for satisfying the demand of metering station, tank farms, marine loading docks and blending plants, etc. ● No Abrasion The 3Z Twin Slip (D.B.B) plug valve can do complete isolation without leakage in a design pressure. The design of valve is such that the seals do not come in contact with the valve body at any time during opening or closing of the valve. Only at the last moment of closing do the seals come in contact with the body, the force consists of only a pressure force. This pressure force is perpendicular to the seating area and a shearing force is thereby eliminated. When the valve is In the opening position, the seal are separated from the body, and maintained at this state during plug rotation. This eliminates abrasion forces from the seals and extends seal life. ● Double block bleed With the 3Z Twin Slip (D.B.B) plug valve, there is an up-stream and down-stream seal, and bleed point in between. This one valve substitutes for two valves, and one spool (drain). The spool sends any leaking fluid from the valve to the tank. The bleed system on the 3Z double block and bleed is installed for proving zero leakage. This ensure that if any leakage were to occur it would be eliminat