Single-flow double-metering liquefied natural gas filling machine

Abstract

The invention discloses a single-flow double-metering liquefied natural gas filling machine. The single-flow double-metering liquefied natural gas filling machine comprises a shell. A backflow pipeline, a gas return pipeline, a circulation pre-cooling pipeline and a filling pipeline are arranged in the shell. The backflow pipeline is connected to the filling pipeline through the circulation pre-cooling pipeline. The gas return pipeline is connected to the backflow pipeline. One end of a check valve is connected with the circulation pre-cooling pipeline through a temperature sensor, and the other end of the check valve is connected to the filling pipeline. The gas return pipeline comprises a gas filling machine backflow opening, a returned gas detecting and metering device, the check valve and a gas return gun. One end of the returned gas detecting and metering device is connected with the gas return gun through a pipeline after passing the check valve, and the other end of the returned gas detecting and metering device is connected with the gas filling machine backflow opening through a pipeline. Due to the fact that the gas filling machine is provided with only one liquid filling pipeline without any other branch, the possibility of gas filling cheating does not exist, a mass metering meter is replaced with the returned gas detecting and meting device, the metering accuracy of the whole gas filling machine is ensured, the problem that the returned gas metering error of the liquefied natural gas filling machine is large is solved, and the cost is reduced.

Description

technical field [0001] The invention belongs to the technical field of liquefied natural gas filling application, and relates to a single-flow double-metering liquefied natural gas filling machine. Background technique [0002] Liquefied Natural Gas (LNG) is a clean and efficient energy source. With the continuous development of my country's LNG vehicle industry, the demand for LNG filling stations is also increasing, and LNG filling machines are increasingly being used. widely used. [0003] At present, due to the high pressure of the vehicle-mounted bottle in the domestic market, in order to facilitate the filling of LNG, two mass flow meters are generally used in domestic LNG refilling machines, which are used to add liquid to the vehicle-mounted bottle and the vehicle-mounted bottle respectively. Decompression and return gas for metering. Due to the gas-liquid two-phase characteristics of LNG, it is still impossible to accurately measure the return gas volume even if a ...

AI Technical Summary

Problems solved by technology

[0005] Thirdly, in order to achieve the metering accuracy of the gas dispenser in the current domestic LNG dispenser, a branch is added behind the main flow meter, which will provide opportunities for cheating when refueling.

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