Pipe joint, gland, and method for joining pipes

A pipe joint, wherein:

• a spigot formed in one pipe is inserted into a socket formed in another pipe,
• a first tapered surface that decreases in diameter progressively toward a rear side of the socket is formed on an inner circumference of the socket,
• a seal member insertion space is formed throughout an entire circumference between the first tapered surface and an outer circumference of the spigot,
• an annular seal member which seals between the inner circumference of the socket and the outer circumference of the spigot is inserted into the seal member insertion space,
• a gland for pressing the seal member from an opening end face of the socket into the seal member insertion space is externally fitted to the spigot and faces the opening end face of the socket from outside,
• the gland is attached to the socket through a plurality of fasteners,
• the seal member has, at one end part in an insertion direction, a bulb part that is compressed in a pipe diameter direction and exerts a sealing function,
• a guide part for guiding the bulb part of the seal member from the opening end face of the socket into the seal member insertion space is formed on the inner circumference of the socket,
• the guide part has a second tapered surface which decreases in diameter progressively toward the rear side of the socket,
• the second tapered surface is formed between the opening end face and the first tapered surface of the socket in a pipe axis direction,
• an angle of inclination of the second tapered surface with respect to a pipe central axis is greater than an angle of inclination of the first tapered surface with respect to the pipe central axis,
• a toric first protrusion integrally formed with the gland comes into contact with the opening end face of the socket,
• a fastener insertion hole through which a fastener is inserted is provided in the gland,
• a concave portion that is surrounded by the toric first protrusion is provided in the gland,
• the first toric protrusion is formed further inward than the fastener insertion hole in the pipe diameter direction,
• another end part in the insertion direction of the seal member is fitted into the concave portion of the gland,
• a diameter of an end part of the second tapered surface on the opening end face of the socket is smaller than an internal diameter of the toric first protrusion of the gland,
• in a case where the seal member is inserted into the seal member insertion space in a state in which the seal member is externally fitted to the spigot, a bulb center part between an inner circumference and an outer circumference in the pipe diameter direction of the bulb part of the seal member is located further inward in the pipe diameter direction than the end part of the second tapered surface on an opening end face side of the socket,
• a required space is formed between an end face of the spigot, an outer circumferential face of the spigot connected with the end face of the spigot, an inner circumference face of the socket, and a deep end side face of the socket,
• the spigot is movable in the required space in the pipe diameter direction and the pipe axis direction with respect to the socket,
• the one pipe and the another pipe are configured to be bendable to each other.