For a pressure vessel at normal pressure that contains Class A flammable materials, are there any special procedures required for such a vessel?
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The pressure vessel has a capacity of 10 cubic meters and is used to hold Class A flammable material (dichloroethane). Are there any special procedures required for this vessel? Are there any special requirements for container inspection and pressure testing? Is it necessary to inspect and pressure-test it as a pressure vessel?
The boiling point of dichloroethane is 83–84°C, with a saturated vapor pressure of 13.33 kPa at 29.4°C. According to the \"Design Code for Storage Tanks in Petrochemical Storage and Transportation Systems\" SH/T 3007-2014, section 4.2.5, for storing liquids of categories A and B whose boiling point is 45°C or higher, or whose saturated vapor pressure is not greater than 88 kPa at 37.8°C, floating roof tanks or internal floating roof tanks should be used. For other liquid chemical products of Class A-B and Class B-A that require special storage conditions, fixed-roof storage tanks, low-pressure storage tanks, or horizontal storage tanks with a capacity of 100 m3 or less can be used; however, one of the following measures must be taken: install a nitrogen or other inert gas sealing system to capture and handle the gases released from the tank, or install a nitrogen or other inert gas sealing system to keep the storage temperature 5 °C or lower than the liquid’s flash point. Dichloroethane can be stored in atmospheric or low-pressure storage tanks such as fixed-roof tanks, low-pressure tanks, and horizontal tanks with a capacity of 100 m3 or less; however, a nitrogen or other inert gas sealing system must be installed. Atmospheric or low-pressure tanks are not subject to the regulations applicable to pressure vessels.
What about pressure testing after manufacturing? Is just a water retention leak test sufficient?