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Analysis of the differences between apparent density and specific gravity: Since the relative error between the mass calculated from specific gravity and the standard density is less than 50,000 parts per million, this value is far smaller than the measurement errors that occur during the transfer of oil products. China’s petroleum industry stipulates that in daily transfer and measurement operations, the specific gravity is used instead of the standard density for calculations. And what is directly obtained through on-site measurement is apparent density ； apparent temperature ； Three oil temperature values. It is impossible to obtain the weight density directly. The standard density must be calculated by referring to Table 59B, \"Standard Density Table for Petroleum Products\", in GB/T1885—1998 \"Petroleum Measurement Tables\", based on the apparent density and apparent temperature. The specific gravity is then calculated by using the converted standard density and oil temperature, with reference to the \"Specific Gravity Table for Petroleum Products\". At a standard temperature of 20°C, apparent density = standard density ； Weight density = Standard density – 1.1 kg/m3. 1.1 kg/m3 is the air buoyancy value of the oil product. In other words, at the standard temperature of 20°C, the specific weight is less than the apparent density. When converting the volume of varnish, the volume calculated using the weight density is greater than that calculated using the apparent density. ' `0 k3 D: c% f# X 1: Apparent density ； Relationship between standard density and weight-based density 2 i) G8 I: \$ _!W: m6 e- ]/ k 1. Apparent density ； The apparent temperature and standard density are specified in GB/T 1885—1998, Petroleum Measurement Tables, Section 59B, Standard Density Table for Petroleum Products. The temperature interval in this table is 0.1°C, the specific density values are odd integers, and the density interval is 2 kg/m3. The standard density intervals identified varied between 1.9 and 2.1 kg/m3. It can be seen from this table that the specific gravity is… ； Apparent temperature is linearly proportional to standard density. In other words, the apparent density increases, the apparent temperature increases, and its standard density increases as well. An increase of 0.1°C in temperature results in an increase of 0.1 kg/m3 in standard density ； Apparent density increases by 0.1 kg/m3, while standard density increases by 0.095~0.105 kg/m3. Conversely, the apparent density decreases, the apparent temperature decreases, and its standard density decreases. 2. Standard density ； Oil temperature and specific gravity are specified in the \"Table of Specific Gravities for Petroleum Products\" established by the petroleum industry. The temperature interval in this table is 0.1°C, the standard density values are even integers, and the density interval is 2 kg/m3. The measured bulk density ranged from 1.9 to 2.1 kg/m3. At a standard temperature of 20°C, the specific weight = standard density – 1.1 kg/m3. It can be seen from this table that the specific gravity is… ； Apparent temperature is linearly inversely proportional to standard density. In other words, as the standard density increases and the oil temperature rises, its specific gravity decreases. For every 0.1°C increase in oil temperature, the specific gravity decreases by 0.1 kg/m3 ； The standard density increases by 0.1 kg/m3, while the weight density increases or decreases by 0.095~0.105 kg/m3. Conversely, as the standard density decreases and the oil temperature drops, its specific gravity increases. 3. Apparent density ； apparent temperature ； The relationship between oil temperature and specific gravity can be seen from the above two points; to increase the specific gravity. It depends on whether the apparent density increases or the apparent temperature increases ； Oil temperature decreases. Conversely, the weight density decreases. It depends on whether the apparent density decreases or the apparent temperature decreases ； Oil temperature increases. II: Differences between apparent density and weight density in practical applications. # k3 K( ~# I3 y% o6 n( e$ g For example, according to the regulations of the petroleum industry, areas classified as Category A experience spring and winter seasons from January to March and from October to December each year ； April to September is summer and autumn. During spring and winter, the temperature changes little each day. Therefore, the change in the specific gravity of gasoline is not significant either. Therefore, it is sufficient to measure the density twice, in the morning and evening. During summer and autumn, the temperature changes significantly throughout the day. The maximum change can reach 5°C. Therefore, measuring the density only twice in the morning and evening is not sufficient; it is necessary to take another measurement at noon as well. It protected the interests of a large number of customers. It also helps to maintain the company’s image and reputation. Since apparent density and bulk density are affected by temperature. Seasonal variations in regional temperatures are very pronounced. From 0°C at the bottom to 40°C at the top. Therefore, the difference between the apparent density and the specific gravity of gasoline is related to temperature: 7 J7 ^: Z# P8 N N `# `; D: i Temperature Difference between apparent density and specific gravity (kg/m3) % ‘H8 e 30℃~40℃ 1.5~~3.0 The relationship between the apparent density and specific gravity of diesel and temperature is not as significant as that of gasoline; it remains relatively stable, varying basically within the range of 1.0~~2.0 kg/m3. III: Apparent density and specific gravity – the volume of oil delivered) ~" C" Y# ^" R5 L$ S2 ` From the above analysis, it can be seen that the specific gravity is lower than the apparent density; therefore, the volume of oil delivered based on specific gravity is greater than that delivered based on apparent density. The difference in volume between the two methods is related to the difference in weight and density of the oil: the lower the density, the greater the volume difference ； The greater the oil weight, the larger the volume difference. For gasoline, when the weight per ten tons is considered and the density difference is 1 kg/m3, the apparent density is 17 to 20 liters less than the volume corresponding to the actual weight density. For example: if the weight of the hair oil is 10 tons, its mass density is 709 kg/m3, and its apparent density is 710 kg/m3. The volume of the oil at specific gravity is 14,104 liters, while the volume at apparent density is 14,085 liters; the difference in volume is 19 liters. The weight of the hair oil is 20 tons. The volume of the oil at specific gravity is 28,208 liters, while the volume at apparent density is 28,169 liters; the difference in volume is 39 liters. For diesel fuel, per 10 tons, when the density difference is 1 kg/m3, the apparent density results in a volume that is 15–18 liters less than the actual density volume. IV. Oil dispatch from storage facilities and oil receipt at gas stations: In accordance with relevant regulations, the volume of oil dispatched from a storage facility is determined by dividing the weight by the specific gravity; the actual amount of oil delivered is then calculated using a flow meter that has been verified as accurate by the provincial technical supervision authority. Since the weight density is determined only after conversion by a meterologist in accordance with relevant regulations, and flow meters are valid measuring instruments, the oil dispensing from the oil depot complies with these regulations, ensuring that the quantity delivered is accurate. There is no valid basis for using scales to measure the weight of fuel at certain gas stations: 1. It is not clear whether the scales in use have been tested and are still within their valid period ； 2. Is the scale it was used with within its valid range? ； When using a 100-ton scale to weigh a 30-ton vehicle, is the accuracy within 10 kilograms? ； 5 @3 P- `6 D! @3B; S4 @ 3: Whether the location where the vehicle is parked and the surrounding area of the scale are appropriate. $