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V. Precautions for selecting equipment flanges, pipe flanges, and gaskets 1. Attention should be paid to the allowable stress at the operating temperature of the flanges； 2. The type of seal surface on the pipe flange must match the required pressure class ； 3. Attention should be paid to the applicable range of gaskets – non-metallic gaskets should not be used for internal gaskets ； 4. If it is necessary to make openings in the flange cover, a strength check is usually required; it cannot be handled carelessly ； 5. Note that the notation styles for European and American standards are different ； 6. Note that C2 was not deducted in the calculation of the flange. The C2 on both sides should be deducted for the floating head flange ； 7. Above 300 degrees Celsius, do not use SO for flanges; use WN instead ； 8. The flange for the tube box should be selected to be a slightly larger size, so it won’t be too tight ； 9. Standard gaskets should be used for floating head flanges; no separate drawings are required ； 10. Asbestos rubber gasket pads should not be used ； VI. Pressure Testing 1. When using air pressure in place of water pressure, strict adherence to the relevant regulations is required; no arbitrary actions are permitted ； 2. Used containers holding flammable materials must be thoroughly purged before pressurization testing can be carried out ； 3. Many owners ask the manufacturer questions regarding the water used for pressure testing, mainly concerned about the contents in tap water (which is generally used for this purpose), and those who are more stringent even require a test report. VII. Stainless steel containers: Forming is achieved through cold working; hot working is not recommended. Heat treatment alters the austenite lattice composition. If heat treatment is applied, solution heat treatment or stabilization heat treatment is required. Heat treatment: Austenitic steels generally do not require heat treatment after welding, unless the thickness is 50 mm or more ； If the deformation amount after cold working is greater than 15%, heat treatment is performed. Austenitic steel is non-magnetic and cannot be inspected by magnetic particle testing; RT is recommended, as UT testing is not sensitive enough. Definitions of pickling, passivation, and blue spot testing. See CD130A3-84 Appendix B, D. For welding, the stainless steel casing must be welded using the same material; there must also be a transition layer between stainless steel and carbon steel, such as in the design of cluster seats. For intergranular corrosion testing, CuSO4 cannot be used; however, the oxalic acid test (a screening test) can be employed. It is not suitable for screening austenitic stainless steels containing Mo or Ti using the 65% nitric acid method. 【Measures to prevent intergranular corrosion: 1) Solution treatment 2) Reducing carbon content in steel 3) Adding elements that stabilize carbides (Nb, Ti, Ni)】 VIII. Regarding vertically installed storage tanks manufactured on-site 【Temporarily unavailable; not yet organized】