Seeking expert help to calculate valve leakage rate

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The customer is inquiring about electric cut-off valves. The valve is required to achieve a leakage rate of grade VI according to GB/T4213-92~~I checked the relevant standards. I really can’t calculate the specific amount of leakage. I need an expert to help with the calculation. Thank you~~ The pressure of the valve is 16 kilograms. The diameters are DN100, DN150, DN200, DN250, and DN300 respectively. The medium temperature is 20 degrees Celsius, and the media involved are diesel and gasoline. The following are the provisions specified in the standard – GB/T4213-92, which defines six levels for leakage; the specific details are shown in the table below. The lowest level is Grade I, for which no specific requirements apply; the highest level is Grade VI, also known as the bubble level. When the leakage rate exceeds 0.5% of the KV value, testing can be waived. Leakage level, test medium, test procedure, maximum valve seat leakage rate: Ⅰ to be determined by the user and the manufacturer; Ⅱ L or G15×10-3×valve rated capacity, 1/h; Ⅲ L or G110-3×valve rated capacity, 1/h; Ⅳ L1 or 210-4×valve rated capacity, 1/h; G1 Ⅳ－S1 L1 or 25×10-4×valve rated capacity, 1/h; G1 Ⅳ－S2 G12×10-4×△P×D, 1/h; Ⅴ L21.8×10-7×△P×D, 1/h; Ⅵ G13×10-3×△P×(leakage rate specified in the table below). Note: ① △P is in KPa. ②D is the valve seat diameter, in mm. ③It refers to the measured value of the volumetric flow rate of a compressible fluid under standard conditions of an absolute pressure of 101.325 KPa and an absolute temperature of 273 K. ④ Test procedure “1” indicates △P = 0.35 MPa, with water as the medium ； Test procedure “2” indicates that △P is equal to the operating pressure difference, and the medium is water or gas. Valve seat diameter (mm), Leakage volume (mL/min), Number of bubbles per minute: 25, 40, 50, 65, 80, 100, 150, 200, 250, 300, 350, 400. Values: 0.15, 0.30, 0.45, 0.60, 0.90, 1.70, 4.00, 6.75, 11.1, 16.0, 21.6, 28.4. Number of bubbles per minute: 1, 2, 3, 4, 6, 11, 27, 45. – – – – – Note: ① The number of bubbles per minute is measured with a tube having an outer diameter of 6 mm and a wall thickness of 1 mm, submerged vertically at a depth of 5–10 mm underwater; the surface of the tube end must be smooth, without any chamfers or burrs. ②If the valve seat diameter differs by more than 2 mm from one of the values listed, the leakage coefficient can be determined by analogy, assuming that the leakage amount is proportional to the square of the valve seat diameter. The rated capacity is determined using the following formula:
△P＜http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image002.gif·P1 → …;
△P≥http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image002.gif·P1 → …
For liquids: http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image006.gif; for gases: Qg＝4.73Kvhttp://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image008.gif http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image010.gif.

In the table:
Q1 – Liquid flow rate, in m3/h;
Qg – Gas flow rate under standard conditions, in m3/h;
KV – Rated flow coefficient;
Pm＝http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image002_0000.gif, in KPa;
P1 – Absolute pressure before the valve, in KPa;
P2 – Absolute pressure after the valve, in KPa;
△P – Pressure difference before and after the valve, in KPa;
t – Temperature of the test medium, taken as 20℃;
G – Specific gravity of the gas; for air, it is 1 http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image004_0000.gif. Relative density (for water within a specified temperature range, it is http://www.china-tjf.com//shu/images/shuM2/shu-1-6_clip_image005.gif = 1)