Patent ID: 9719618
Date: 2017-08-01
CPC Classifications: F16L

Claim:
1. A pipe joint in which a spigot formed at an end of one pipe is inserted into a socket formed at an end of another pipe, the pipes being joined to each other, the pipe joint comprising: an annular sealing material interposed and compressed between an inner circumferential surface of the socket and an outer peripheral surface of the spigot to exhibit desired sealing properties; a push ring fastened to the socket to keep the sealing material in a compressed state in which the sealing material is interposed between the inner circumferential surface of the socket and the outer peripheral surface of the spigot, the push ring having a stepped concave surface formed thereon, the stepped concave surface having a bottom surface and being configured to prevent an end of the sealing material fitted into the stepped concave surface from moving in a diameter expansion direction, the push ring being configured to push the sealing material into a gap between the inner circumferential surface of the socket and the outer peripheral surface of the spigot; a centering mechanism configured to guide the push ring in a pipe diameter direction such that a center of the push ring is aligned with a pipe axis when the push ring pushes the sealing material into the socket, the centering mechanism comprising a first tapered surface formed on the push ring and being in contact with an outer periphery of the end of the sealing material, the first tapered surface being formed in a vicinity of the bottom surface of the stepped concave surface and gradually expanded in diameter towards the socket; an annular lock ring fitted in a lock ring accommodating area defined between the inner circumferential surface of the socket and the outer peripheral surface of the spigot; and a projection formed on the spigot and engaged with the annular lock ring to secure the annular lock ring within the lock ring accommodating area, wherein the first tapered surface and the bottom surface are separate surfaces.