Natural gas tank car parking braking system

The utility model discloses a natural gas tank car parking braking system. The natural gas tank car parking braking system comprises a gas pump, a gas storage barrel, a parking braking valve and a braking branch pump; the gas pump is connected with the gas storage barrel through a gas tube, and the parking braking valve is connected to a pipe for connecting the gas storage barrel to the braking branch pump in series, wherein the parking braking valve comprises a braking valve body and a brake handle, the braking valve body is used for controlling a gas path from the gas storage barrel to the braking branch pump to be opened and closed when being opened and closed, and the brake handle is used for controlling the braking valve body to be opened/closed in a one-direction mode. Compared with the prior art, the natural gas tank car parking braking system has the advantages that when the braking handle is switched into the opening state, parking braking takes effects, a gas adding connector is exposed out, and charging work can be done; when the brake handle is switched into the closing state, the charging work cannot be done. Meanwhile, a quick coupler is adopted as a pipe connector, so that the natural gas tank car parking braking system is rapid and convenient to connect and high in reliability.