Socket-Fusion Welding For PP
In this method, fusion joining is carried out using heated tools with the fitting overlapping the pipe. No additional materials are used. The pipe end and socket fitting are heated to fusion temperature using a heating bush and heating spigot respectively and then pushed together.
• Set up welding shelter if required.
• Heat tool to welding temperature.
• Clean heating device with lint-free cloth using clean water or clear spirits.
• Check welding temperature. (260°C +/-10°C).
• Machine the square cut pipe end to be welded in accordance to manufacturers recommendations and if necessary, mark depth of entry mark.
• Push fitting and pipe simultaneously onto the spigot and sleeve respectively of the heated tool as far as the stop or depth of entry mark.
• Observe the recommended heating times as per table 8.3.1 (Heating Time).
• Withdraw fitting and pipe from spigot and sleeve and push them together immediately without twisting as far as the stop or depth of entry mark. Table 8.3.1 (Changeover Time).
• Allow joint to cool.
• Table 8.3.1 (Cooling Time).
Table 8.3.1: Recommended Values at Ambient for Heated Tool Socket-Fusion
Socket Fusion Welding Diagram
Socket Fusion Welding
Saddle/Sidewall Fusion Welding For PP
The technique to join a saddle to the sidewall consists of simultaneously heating both the external surface of the pipe and the matching surface of the “saddle” type fitting with concave and convex shaped heating tools until both surfaces reach proper fusion temperature. This may be accomplished by using saddle fusion machine that has been designed for this purpose. Saddle fusion, using a properly designed machine, provides the operator better alignment and force control, which is very important to fusion joint quality. The Plastics Pipe Institute recommends that sidewall-type fusion joints be made only with a mechanical assist tool unless hand fusion is expressly allowed by the pipe and/or fitting manufacturer. If hand saddle fusion must be performed, it should be done only by Polyethylene Joining Procedures.