Device for judging air leakage degree of small coal pillar by using tracer gas and application method

The invention discloses a device for judging the air leakage degree of a small coal pillar by using a tracer gas, which comprises a tracer gas steel cylinder, a pressure reducing valve, a pressure stabilizing valve, a flow stabilizing valve, a flowmeter, a four-way pipe, a ball valve I, a ball valve II, a ball valve III, a connecting guide pipe, an external guide pipe, a shell and an external guide pipe connector, wherein the four-way pipe comprises a pipe arm I, a pipe arm II, a pipe arm III and a pipe arm IV, the top part of the gas tracer steel cylinder is provided with the pressure reducing valve, the pressure reducing valve, the pressure stabilizing valve, the flow stabilizing valve, the flow meter and an interface of the pipe arm I are sequentially connected through the conducting guide pipe, the ball valve I is arranged inside the ball arm I, the ball valve II is arranged inside the pipe arm II, the ball valve III is arranged inside the pipe arm III, interfaces of the pipe arm II and the pipe arm III are fixedly connected with two sides of the shell respectively, and the shell is provided with an opening I and an opening II at parts corresponding to the interfaces of the pipe arm II and the pipe arm III. The device disclosed by the invention is a miniaturized device, simple and portable, low in cost and easy to operate. The invention further provides an application method of the device.