Patent ID: 11892375
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 10:
11. A method for inspecting an interior of a conduit and for determining abnormality associated with the conduit, the method comprising:
supplying, by a water supplier, water from a tank to the interior of the conduit through a hose connected to the conduit at a first end of the conduit;
releasing, by an air releaser, air from the interior of the conduit to an outside of the conduit at a second end of the conduit through an air vent tube of an air vent portion placed at the second end of the conduit until an air vent valve closes, wherein the second end is distinct from the first end, and, when an air vent valve is closed, the closed air vent valve prevents the air from being released to outside the conduit;
pressurizing, by a pressurizer, the interior of the conduit, wherein the conduit is blocked at the first end and the second end, and whose interior is filled with water; and
determining, by a pressure determiner, a pressure value of the interior of the conduit when pressurization ends and a pressure value of the interior of the conduit when a predetermined period of time elapses since stopping the resumed supplying of the water to detect the abnormality of the conduit,
wherein the water supplier supplies water to the interior of the conduit until water that does not contain air is drained from the air vent tube,
wherein the predetermined period of time elapses while the conduit is blocked at the first end and the second end and without receiving further supply of the water, and
wherein the abnormality of the conduit is associated with a change of the pressure value of the interior of the conduit when the predetermined time lapses.