How much pressure can pvc hold after its been drilled and tapped?

[1320wrx]

I am making a resivoir for a auto top off out of pvc. I plan on using 4 inch pvc, on one end of the pipe I plan on capping off the pipe. In the cap I want to drill a 1/4" hole, tap in threads, and install a 1/4 male John Guest fitting wrapped in teflon tape. I will be pressurizing the pipe with 10-20psi of air. Will the joint between the PVC end cap and the JG fitting be strong enough to hold that much PSI for long periods of time?
Steve

 

[wattsupdoc]

Probably at 10-20 psi, it will hold. Be sure to get a good seal with the Teflon. If you have any large pieces with threaded connection, like a 4" female to a 4" male cap, that will be a weak point. The larger threads can be more difficult to seal than the smaller/finer threads, make sense?

 

[1320wrx]

yea that does makes sense, thanks for the help