The invention relates to a large
train crane
pipe loading metering
system which comprises a
naphtha flowmeter, a
gasoline flowmeter and a diesel oil flowmeter, a large loading valve, a small loading valve, a stop valve and a crane
pipe. The loading valves and the stop valve are located on an oil conveying header
pipe, a
naphtha pipeline and a
gasoline pipeline are connected in parallel to be used in common, and the valves are arranged for loading
type selection. The
gasoline flowmeter is installed on the ground, the backpressure of the flowmeter is improved, oil product
vaporization is prevented, oil product metering accuracy and the automatic metering level are improved, and the loading metering
system is controlled by a DCS
control unit. Flowmeter on-line calibration ports are reserved in the oil conveying header pipe. According to the large
train crane pipe loading metering
system, high-precision
mass flowmeter on-line calibration is utilized, the problems of inaccurate metering caused by off-line
verification of the flowmeters are solved, single
train loading metering is achieved after the system is implemented, the largest error is smaller than 200 kg, the accuracy of the whole train is larger than 0.2, and a trade custody transfer metering method and the calibration method are accepted by oil product clients.