Fig.1: Gasket Insertion
The inside of sockets and the outside of spigots should be cleaned up to the insertion depth. Gaskets should be wiped clean and inspected for damage. The gasket should then be placed into the socket groove, rounded end entering first. Seating the gasket is made easier by forming the gasket into a loop during insertion. The heel of the gasket should fit uniformly into the retainer seat. On pipes larger than 12”, additional loops may help in placing the gasket in the seating.
Fig.2: Lubrication
Ensure that the spigot end is properly chamfered or rounded to avoid tearing of the gasket. Clean away all foreign matters from the contact area of the pipe. Apply a thin film of recommended lubricant to the mating surface of the gasket. Avoid spray-on lubricants as these may not provide enough lubrication. Avoid petroleum-based lubricant as it may damage the gaskets. Once lubricated, do not let the lubricated area touch the ground or other contaminants, the compromised seal could result.
Fig.3: Pipe and Fitting and Assembly
Spigot should be inserted in the socket. If the socket is pushed, the gasket may be displaced. Align and center the spigot in the socket and keep it in this position. Now gently push the spigot into the socket by suitable mechanical means, maintaining the alignment and level. A suitable gap should be left between the spigot end and the bottom of the socket to take care of any axial movement, deflection or temperature variation. To ensure this, two band marks are made near the spigot end. These bands act as a ‘Go’ and ‘No-Go’ gauge. After jointing, the end of the socket must end between these two bands. If moderate force does not result in a solid seal, remove the pipe and inspect for foreign matters, improper lubrication or misaligned gasket. Once you are certain of a solid seal, joint deflection can be applied within the permissible limits.
Fig.4: Inspection of Joint
Verification of the gasket’s position is easily accomplished with a feeler gauge. Insert the gauge into the joint until it touches the gasket. Check the gasket position all around the joint, making note of the depth required to contact the gasket. Any changes in depth indicate the gasket has slipped out of place. If this is the case, disassemble joint and clean all pipe contact areas and gasket. Once inspected for the fault, reassemble using the guidelines above.
