Abstract: A seal apparatus provides sufficient sealing and is compact and inexpensive. The seal apparatus includes a thread part screwed to the screw fastening part of a hollow component; a seal part that moves along an axis of the screw part and comes into pressure contact with the screw fastening part of the hollow component; a stopper part fixed to the screw part that restricts the movement of the seal part; a pressed part that moves the seal part into pressure contact with the screw fastening part; a spring disposed between the pressed part and the stopper part; and an accumulator formed between the stopper part and the seal part and into which a test fluid which is introduced into the hollow component for inspection flows.

Abstract: A gas-tight plug is attachable by pressing it against an opening portion of a hollow component, the gas-tight plug being inserted into the opening portion using the force of pressing to be automatically aligned so that if the positions of a plurality of opening portions vary within an allowable tolerance, the axial directions of all the opening portions and the axial directions of the respective gas-tight plugs are automatically caused to coincide. A gas-tight plug includes an end portion, a contact part of a base portion end of the gas-tight plug coming into contact with a base of the pressing mechanism has a circular flat surface coaxial with the end portion, and the circular flat surface has a diameter more than 0.12 times and less than 0.2 times a total length of the gas-tight plug.

Abstract: A seal apparatus provides sufficient sealing and is compact and inexpensive. The seal apparatus includes a thread part screwed to the screw fastening part of a hollow component; a seal part that moves along an axis of the screw part and comes into pressure contact with the screw fastening part of the hollow component; a stopper part fixed to the screw part that restricts the movement of the seal part; a pressed part that moves the seal part into pressure contact with the screw fastening part; a spring disposed between the pressed part and the stopper part; and an accumulator formed between the stopper part and the seal part and into which a test fluid which is introduced into the hollow component for inspection flows.

Abstract: A gas-tight plug is attachable by pressing it against an opening portion of a hollow component, the gas-tight plug being inserted into the opening portion using the force of pressing to be automatically aligned so that if the positions of a plurality of opening portions vary within an allowable tolerance, the axial directions of all the opening portions and the axial directions of the respective gas-tight plugs are automatically caused to coincide. A gas-tight plug includes an end portion, a contact part of a base portion end of the gas-tight plug coming into contact with a base of the pressing mechanism has a circular flat surface coaxial with the end portion, and the circular flat surface has a diameter more than 0.12 times and less than 0.2 times a total length of the gas-tight plug.