Welcome! Here are the website rules, as well as some tips for using this forum.
If you've found help here, check back in to let us know how everything worked out.
It's a great way to thank those who helped you.
What are these test ports?
What are these test ports? No one can give me an answer.
They appear to be 1/8: NPTX (?) Caps. Shrader valves? Or Flare Caps.
They are for testing pressure on a gas train on a large gas burner.
They are the brass fittings screwed into special places that need to have gas pressure checked for testing and adjustments.
In the first picture, there are two. On on a high pressure sensor, the other on the side of a ball valve shut-off. The second picture has the same one on the high pressure cut-out switch. The third picture has one on the line going to the pilot to check the gas pressure.