Abstract: In order to provide a supply and exhaust pipe comprising a drop-off prevention mechanism, particularly effective for pipes with a large diameter, to increase bending strength and sealing efficiency, formation of a hemmed section A at an top edge of an insert portion 4 can eliminate the occurrence of buckling and increase bending strength. Furthermore, an O-ring for sealing can improve sealing efficiency and also can make itself follow a deformation of the pipe by forming it into a mushroom shape to establish close contacts to the pipe at two points, namely a neck 8b and a part of the circumference 8c of a cap 8a. Furthermore, a drop-off prevention mechanism of the pipe has a wide sliding piece 12, and an arc 17 with a curvature adapted to the curvature of the pipe is formed on the lower surface of the sliding piece 12, to stabilize its sliding.

Abstract: In order to provide a supply and exhaust pipe comprising a drop-off prevention mechanism, particularly effective for pipes with a large diameter, to increase bending strength and sealing efficiency, formation of a hemmed section A at an top edge of an insert portion 4 can eliminate the occurrence of buckling and increase bending strength. Furthermore, an O-ring for sealing can improve sealing efficiency and also can make itself follow a deformation of the pipe by forming it into a mushroom shape to establish close contacts to the pipe at two points, namely a neck 8b and a part of the circumference 8c of a cap 8a. Furthermore, a drop-off prevention mechanism of the pipe has a wide sliding piece 12, and an arc 17 with a curvature adapted to the curvature of the pipe is formed on the lower surface of the sliding piece 12, to stabilize its sliding.