A studding outlet is a flange shaped connection welded to a vessel or pipe surface on one side and drilled with tapped holes on the other. Unlike a standard flange the holes do not pass through; the studs thread into the body.
Where it is used
- Manway and nozzle connections on pressure vessels and tanks
- Branch outlets on large bore lines
- Connection points on heat exchanger shells
- Tight locations where a short neck is required
Its advantage is that no separate nozzle pipe is needed: the part is welded straight to the shell, which makes the connection short and rigid.
Flat bottom and radius back
- Flat bottom: The underside is flat and suits flat surfaces or large diameter vessels. It is the most common type.
- Radius back: The underside is machined to the curvature of the shell it sits on. It is preferred on smaller vessels and at high pressure so the weld preparation seats evenly all round. Machining adds cost, but improves weld quality and stress distribution.
When ordering
These parts are usually made to order. The information needed:
- Flange size, pressure class and face form
- Diameter and radius of the surface it will be welded to (for radius back)
- Thread size, thread depth and hole count
- Material grade and certificate level
- Weld preparation form where required
Thread depth matters: the stud must engage the full thread, otherwise the joint cannot carry the calculated load.
See our services page for our fabrication scope and send dimensions through the enquiry form.
FAQ
How does a studding outlet differ from a normal flange?
Its holes are tapped rather than through drilled, and it welds directly to the vessel or pipe without a separate nozzle.
Why choose radius back?
On smaller vessels it makes the weld preparation seat evenly all round and improves stress distribution.
Is it available from stock?
Usually made to order; lead time is given with dimensions and pressure data.
Send us your material list; we reply with price and lead time the same day.
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