Teflon tape is a thread lubricant, not sealant. Using the sch 80 nipple will work fine as long as you apply pipe sealant when you replace it. If you are getting enough vibratioin to have a fitting come loose it's time to do some pump maintenance.
Vibration?
1.5" female outlet out the top of a lake pump. Mounted tight, plumbed tight., taped heavily. Why does the nipple go loose every now and again? Note the dirty spray on the elbow from the gap. Sch80 nipp.
![Blue Fluid Wood Gas Pipeline transport]()
