APPARATUS FOR TESTING MULTIPLE PIPE AND METHOD FOR TESTING MULTIPLE PIPE

PURPOSE: A multiple pipe inspection device and an inspecting method for multiple pipe are provided to measure the concentration of the tracer gas and to inspect a defect site with a non-destruction method. CONSTITUTION: A multiple pipe inspection device comprises a pair of couplings(21,23), a tracer gas spray unit(30), a vacuum pump(32) and a tracer gas detection unit(34). The couplings are respectively combined in both ends of multiple pipe. The couplings seal a first space(26) and a second space(28). The first space is between the outer wall of an first pipe(12) and the inner wall of a second pipe(14). The second space is divided with an inner area of the first pipe. The tracer gas spray unit sprays the tracer gas to one of the first space and the second space. The vacuum pump inhales the gas remaining in the first space and the second space. The tracer gas detection unit detects the tracer gas from the inhaled gas.