Tham khảo tài liệu 'gas station construction and maintenance, petroleum systems contractor nevada and arizona_6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Simpo PDF Merge and Split Unregistered Version - http UFC 3-460-03 21 JANUARY 2003 . During the fueling operation the operator must continuously verify the operating tank fuel level to ensure the tank does not drop below the tank low level. Verify by checking the liquid level gauge at the tank. . Night Shutdown. At some locations it is common practice to shut down the system at night. This may cause the system pressure to drop into the vacuum range especially during hot weather where warm fuel cools in underground piping. Air can get into the system through hydrant pit valves and the HSV check-out stand valves. This can be prevented by leaving the system on or by using airtight covers on the valves. . Leak Detection. A rapid method of checking for leaks in the hydrant system is to leave the system in the automatic idle mode and count the number of times it must be re-pressurized in a given period of time. Experience will tell how many times is too many. Such a problem could indicate an internal leak through a system automatic or manual valve pressure relief air eliminator or drain line or an external leak through the system piping or components. 71 Simpo PDF Merge and Split Unregistered Version - http UFC 3-460-03 21 JANUARY 2003 Chapter 7 FUEL STORAGE TANKS . General Information. The majority of the aboveground storage tanks used for Air Force petroleum products are built according to API Std 650 Welded Steel Tanks for Oil Storage API Std 653 and Air Force standard designs. See Figure . Figure . Air Force Standard Tank. New belowground horizontal cylindrical storage tanks must be constructed in accordance with UL 58 Steel Underground Tanks for Flammable and Combustible Liquids and conform to environmental requirements of 40 CFR 280 Technical Standards and Corrective Action Requirements for Owners and Operators of Underground Storage Tanks UST current edition and typically should be double-walled Type II .
