The plastic drums have two bungs on them. One is a coarse thread which I have found is called a 2" buttress thread, and from what I read, the other is supposed to be a 2" NPT (taper). The problem is that I believe that it is actually a 2" NPS (straight).
If I try to install a 2" NPT PVC fitting, it only threads in about two turns before getting really tight where the plug that came with the drum threads in 4 or 5 turns and seals on the gasket, not on the threads.
I was hoping to be able to use 2" NPT PVC fittings to hook up to the 2" fine thread bung.
What have other people done that are using drums for cutting fluid storage? Coat the PVC fitting in silicone/sealant and crank it in... or is there a proper adapter for the fine thread hole?
I did quite a bit of Google searching and didn't turn up anything. There are plenty of adapters from the 2" buttress thread to 2" PVC, but none from the 2" fine thread to 2" PVC.
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