The invention belongs to the technical field of pipeline detection, and particularly relates to a connecting
pipe air tightness detection device which comprises a supporting plate, a holding
assembly and two detection assemblies. The holding
assembly and the two detection assemblies are arranged on the supporting plate, an air outlet of a detection
electromagnetic valve of each detection
assembly is connected with one opening of a detection tee joint through an air
pipe, and a second opening of the detection tee joint is connected with a
barometer. The detection outer cylinder is connected to a cylinder push rod of the detection cylinder, the detection outer cylinder is provided with a long-strip hole, the detection inner cylinder is provided with an interface, the detection spring and the detection inner cylinder are sequentially installed in the detection outer cylinder, and the detection straight joint penetrates through the long-strip hole in the detection outer cylinder and is connected with the interface in the detection inner cylinder. A long connecting
pipe is arranged at the end, away from the detection spring, of the detection inner cylinder and penetrates through the other end of the detection outer cylinder, and a third opening of the detection tee joint is connected with the detection straight joint through an air pipe. According to the invention, automatic detection of the
air tightness of the connecting pipe is realized, and the detection quality is improved.