Method of manufacturing a joint for connecting a spigot to the bell of a pipe or coupling

The process of manufacturing an improved bell-gasket assembly comprising, wherein the bell having a mouth at the open end thereof and having a central longitudinally-extending axis, the bell carrying an annularly-extending groove securing an annularly-extending gasket, the groove comprising a bottom, a rearward wall joined to the bottom on the end of the bottom remote from the mouth of the bell, the rearward wall extending towards the longitudinally-extending axis and away from the bottom at an angle less than or equal to 90 degrees, the bottom terminating forwardly at an offset forward wall portion offset to the bottom, the forward wall portion being bent over to extend into the bell, and the gasket being annular and comprising a body of resilient, yieldable material having a bottom wall for seating on the bottom of the annularly-extending groove, a rear portion for abutting the rearward wall of the groove, a sealing lip portion on the side of the body portion remote the bottom wall for engaging a spigot inserted into the bell end, and a forward portion of the gasket offset the bottom of the gasket and being further from the sealing lip portion than the bottom of the gasket for being engaged by the bent over offset forward wall portion and being locked thereby when the foward wall portion is bent over to secure the forward portion of the gasket, the steps of inserting the gasket into the bell with the rear portion of the gasket abutting the rearward wall of the groove and the bottom wall of the gasket abutting the bottom of the groove, and bending the offset forward wall portion over the offset forward portion of the gasket and pushing it into the mouth of the bell over the front portion of the gasket, thereby locking the gasket at the leading edge of the bell whereby when the offset forward wall portion, having been bent over the gasket locks the leading edge of the gasket at the mouth of the bell and with the rearward portion of the gasket abutting the rearward wall, when a spigot is inserted into the bell and engages the sealing lip, the sealing lip is permitted to stretch, decreasing the radial thickness of the gasket as the spigot is inserted, thus reducing the required insertion force for inserting the spigot into the bell without compromising the integrity of the seal and thus precluding the entry of foreign matter into the groove behind the gasket.

A process of manufacturing a tubular member-gasket assembly is provided whereby a gasket is secured in the end of a tubular member, the tubular member having a central longitudinal axis, a mouth at its very end and an annular groove axially spaced from said mouth for receiving the gasket, the annular groove presenting a bottom wall, one end of the bottom wall being proximate the mouth and the other end being axially spaced from said mouth, said bottom wall having at said end proximate said mouth a generally radially-extending wall extending generally away from the central longitudinal axis, and said bottom wall having at its other end axially spaced from the said mouth a radially-extending wall extending toward the central longitudinal axis and being angled about 90 degrees to the bottom wall, the wall extending generally radially away from the central longitudinal axis carrying at its end a longitudinally-extending wall extending towards the mouth and being bent over at its end to provide a bent over portion extending into the end of the generally tubular member, the gasket comprising a body of resilient yieldable material carrying an integral sealing lip, the body having a central longitudinal axis and having opposed ends interconnected by a bottom wall substantially parallel to the axis for seating on the bottom wall of the groove, one opposed end of the gasket terminating in a generally radially-extending wall for engaging the radially-extending wall at the end of the bottom of the groove extending towards the central longitudinal axis of the tubular member and spaced from the mouth, the other opposed end of the gasket comprising a portion extending generally angularly away from the body for being engaged between the bent over portion and the generally radially-extending wall extending away from the central longitudinal axis, the integral sealing lip portion being on the side of the body portion of the gasket opposite the bottom and extending angularly away from the body and the mouth of the tubular portion and terminating at an end portion radially spaced from the body on the side of the body closer the central longitudinal axis of the tubular member than the bottom of the groove, the process comprising the steps of:

• (a) placing the gasket in the mouth of the tubular member with the opposed end of the gasket comprising the portion extending generally angularly away from the body away from the central longitudinal axis abutting against the generally radially-extending wall extending away from the central longitudinal axis of the tubular member and the opposed end of the gasket terminating in a generally radially-extending wall extending towards the central longitudinal axis engaging the radially-extending wall at the end of the bottom of the groove extending towards the central longitudinal axis of the tubular member at an angle of about 90 degrees, and
• (b) bending over the longitudinally-extending wall extending towards the mouth to provide a bent-over portion extending into the end portion of the generally tubular member for sandwiching the opposed end of the gasket comprising the portion extending generally angularly away from the body away from the central longitudinal axis between the bent over portion of the longitudinally-extending wall and the generally radially-extending wall extending away from the central longitudinal axis of the tubular member with the generally radially-extending wall of the opposed end of the gasket abutting against the radially-extending wall extending toward the central longitudinal axis and angled about 90 degrees, thereby locking the gasket at the mouth of the tubular member.