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I. Design specifications stipulate that 1. Steel valves shall be used on oil pipelines. 2. Butterfly valves should not be used. 3. The nominal pressure must be greater than the design operating pressure. When the nominal diameter is ≥50mm, the nominal pressure should be 1.6 MPa higher ； For a nominal diameter of <50 mm, the nominal pressure should be greater than 1.0 MPa. 4. For the quantitative filling of oils and fuels, electro-hydraulic valves can be used as control valves that do not solidify at the operating temperature during filling into barrels ； Electro-hydraulic valves should not be used as they may solidify. 5. For those with a nominal diameter of ≥250 mm and that are operated frequently, worm drive or electric valves with a manual opening function can be used. II. Factor 1: Medium: The corrosion resistance of the material must be taken into consideration; gray cast iron and carbon steel are commonly used. The inlet and outlet valves as well as the drain valve must not be made of gray cast iron. 2. Flow characteristics: ① Gate valves, globe valves, plunger valves, etc. are commonly used to shut off or open fluids, and are suitable for situations with low flow resistance. ②Control valves and throttle valves are commonly used to control flow. ③Plug valves and ball valves are commonly used for direction reversal and flow diversion. Note: Gate valves and stop valves cannot be used to regulate flow. III. Pressure and Temperature Valve Names Gray cast iron valves Malleable cast iron valves Ball-milled cast iron valves Carbon steel valves Operating temperature/°C -15~250 -15~250 -30~350 -29~450 Operating pressure/MPa 1.0 2.5 4.0 32.0 IV. Flow rate and velocity Under a constant flow rate, the velocity determines the efficiency level. Due to the risk of static electricity generation caused by high flow rates, the flow rate of light oils should be less than 4.5 m/s, while that of lubricating oils should be kept below 2 m/s. V. Connection types: 1. Threaded connection, suitable for valves with a diameter of DN50mm or less. 2. Flange connection, suitable for various diameters and pressures; leakage may occur at the flange joint when the temperature exceeds 350°C or high forces are applied. 3. Welded connections are more reliable than flanged connections under similar conditions; however, they are difficult to disassemble and reinstall, and are rarely used in oil depots. If you have any questions, feel free to leave a message!