Inspection method and inspection device

1. A method for inspecting an interior of a conduit and for determining abnormality associated with the conduit, comprising:

supplying water from a tank to an interior of the conduit through a hose connected to the conduit at a first end of the conduit;

while the supplying of the water continues:

releasing air at a second end of the conduit from the interior of the conduit to an outside of the conduit through an air vent tube of an air vent portion placed at the second end of the conduit, wherein the second end is distinct from the first end, wherein the releasing of air continues until water is released through the air vent tube;

determining whether water that does not contain air is drained from the air vent tube placed at the second end of the conduit; and

when it is determined in the determining that water that does not contain air is drained from the air vent tube, stopping the supplying of the water to the interior of the conduit, closing an air vent valve of the air vent portion, and, when the air vent valve is closed, the closed air vent valve of the air vent portion prevents the air from being released to outside the conduit;

resume supplying the water into the interior of the conduit at the first end of the conduit while both the first and second ends of the conduit are blocked, thereby increasing a pressure of the interior of the conduit whose interior is filled with water; and

when the pressure of the interior of the conduit reaches a predetermined pressure value, stopping the resumed supplying of the water;

measuring a pressure value of the interior of the conduit when a predetermined period of time elapses since stopping the resumed supplying of the water, 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

determine, based on a change in the measured pressure value of the interior of the conduit, the abnormality associated with the conduit.

2. The method according to claim 1 , further comprising:

determining that the conduit has the abnormality when the pressure value of the interior of the conduit when the predetermined period of time elapses drops from the pressure value of the interior of the conduit when the pressurization ends, and that the conduit has no abnormality when the pressure value of the interior of the conduit when the predetermined period of time elapses does not drop from the pressure value of the interior of the conduit when the pressurization ends.

3. The method according to claim 1 ,

wherein the performing of the pressurization includes:

determining whether or not the pressure value of the interior of the conduit reaches the predetermined pressure value, and

supplying the water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

4. The method according to claim 2 ,

wherein the performing of the pressurization includes:

determining whether or not the pressure value of the interior of the conduit reaches the predetermined pressure value, and

supplying the water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

5. An inspection apparatus for inspecting an interior of a conduit and for determining abnormality associated with the conduit, comprising:

a water supplier configured to supply water from a tank to an interior of the conduit through a hose provided at a first end of the conduit;

an air releaser configured to release air at a second end of the conduit from the interior of the conduit to an outside 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, the air vent portion includes an air vent valve, and when the air vent valve of the air vent portion is closed the closed air vent valve prevents the air from being released to outside the conduit;

a pressurizer configured to increase a pressure of the interior of the conduit whose both ends are blocked at the first end and the second end by supplying the water and whose interior is filled with water; and

a pressure measurer configured to measure 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 detecting 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.

6. The inspection apparatus according to claim 5 , further comprising:

an abnormality determiner configured to, when the pressure value of the interior of the conduit when the predetermined period of time elapses drops from the pressure value of the interior of the conduit when the pressurization ends, determine that the conduit has the abnormality.

7. The inspection apparatus according to claim 5 , further comprising:

an abnormality determiner configured to, when the pressure value of the interior of the conduit when the predetermined period of time elapses does not drop from the pressure value of the interior of the conduit when the pressurization ends, determine that the conduit has no abnormality.

8. The inspection apparatus according to claim 5 , wherein the pressurizer determines whether or not the pressure value of the interior of the conduit reaches a predetermined pressure value, and supplies water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

9. The inspection apparatus according to claim 6 , wherein the pressurizer determines whether or not the pressure value of the interior of the conduit reaches a predetermined pressure value, and wherein the pressurizer supplies water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

10. The inspection apparatus according to claim 7 , wherein the pressurizer determines whether or not the pressure value of the interior of the conduit reaches a predetermined pressure value, and wherein the pressurizer supplies water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

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.

12. The method according to claim 11 , further comprising:

when the pressure value of the interior of the conduit when the predetermined period of time elapses drops from the pressure value of the interior of the conduit when the pressurization ends, determining, by an abnormality determiner, that the conduit has the abnormality.

13. The method according to claim 11 ,

when the pressure value of the interior of the conduit when the predetermined period of time elapses does not drop from the pressure value of the interior of the conduit when the pressurization ends, determining, by an abnormality determiner, that the conduit has no abnormality.

14. The method according to claim 11 ,

wherein the pressurizer determines whether or not the pressure value of the interior of the conduit reaches a predetermined pressure value, and supplies water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

15. The method according to claim 12 ,

wherein the pressurizer determines whether or not the pressure value of the interior of the conduit reaches a predetermined pressure value, and wherein the pressurizer supplies water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.

16. The method according to claim 13 ,

wherein the pressurizer determines whether or not the pressure value of the interior of the conduit reaches a predetermined pressure value, and wherein the pressurizer supplies water to the interior of the conduit when the pressure value of the interior of the conduit does not reach the predetermined pressure value.