ORB Adapter Fittings

[JohnUlaszek]

At least once a week we get asked about o-ring boss adapters on tech calls. I wrote a blog post about this, but was wondering if folks here had any insight on this, oddly, confusing topic. What do you call them?
https://www.iimuch.com/blogs/news/what-is-an-orb-fitting

[572Camaro]

John!
Thanks for the call last week.

My two cents here regarding your O-ring boss question:

O - ring boss..,

In the nuclear industry,
We refer to your fitting as an “SAE/MS Straight thread (ST)”

I refer to SAE J1926/1 and ISO 11926-1 regarding straight thread boss fittings.

P.S. it’s confusing

P.S.2: The only reason an o-ring boss will fail is if you don’t lubricate the o-ring during installation.., but you already know that.