Air Compressor Piping Layout Questions

[JMarsa]

I'm completing the piping for my compressor and I have a few questions. I already have a auto tank drain at the bottom of the tank. At the end of the run there will be a water/oil separator and a regulator.

Given the not to scale diagram below:





1. Is there any benefit to sloping the line from the tank? I am planning to install a petcock at the bottom of stub 1 to drain any water/sludge.

2. Should I keep stub 1? I'm not sure if they work in air systems like they do for natural gas.

3. Is there any benefit to stub 2? (I'm not planning a petcock here) Should I keep it?

Thanks in advance,

--JMarsa