Branch Connections / WEL
Weldolet - Butt Weld Outlet
Butt-weld outlet covering a wide size range; the most common outlet solution.
Technical Specifications
Key Features
- Butt-weld connection
- Wide size range
- High strength
- Standards compliant
- Weld-friendly
- Cost-effective
Applications
- General piping
- Medium-pressure systems
- Industrial plants
- Petrochemicals
- Water lines
- HVAC
Design Features
- Butt-weld bevel
- Reinforced body
- Standard dimensions
- High mechanical integrity
- Welding compatibility
- Type-tested
Connection Performance
Dimension Table
| Branch Size | Run Size | Outside Diameter (mm) | Height (mm) | Wall Thickness (mm) | Weight (kg) |
|---|---|---|---|---|---|
| 1/2" | 2" | 21.3 | 38 | 3.7 | 0.15 |
| 1" | 4" | 33.4 | 51 | 4.3 | 0.32 |
| 2" | 6" | 60.3 | 64 | 5.5 | 0.75 |
| 4" | 12" | 114.3 | 102 | 7.1 | 2.85 |
| 6" | 16" | 168.3 | 127 | 8.6 | 5.92 |
| 8" | 20" | 219.1 | 152 | 10.3 | 10.45 |
Technical Notes
- 01Most common outlet type.
- 02Weld quality is critical.
- 03Operates across a wide temperature range.
- 04A reliable and economical solution.
What are branch connection (olet) fittings?
Olet-type branch connection fittings are forged components that create a reinforced branch outlet from a run pipe without using a tee. Made to MSS SP-97, the most common types are the weldolet (butt-weld), sockolet (socket-weld) and threadolet (threaded). They are used from 1/2" to 24" under the ASME B31.1/B31.3 piping codes.
Olet types: weldolet, sockolet, threadolet, latrolet, elbolet
An olet body is integrally reinforced: its own wall section compensates the opening cut into the run pipe, so no reinforcing pad is needed. The type follows the branch pipe connection: the weldolet takes butt-welded larger branches; the sockolet (socket-weld) and threadolet (threaded) serve small branches, typically below 2". The latrolet makes a 45° lateral branch and the elbolet takes a branch off an elbow. For branches much smaller than the run — say a 1" outlet on an 8" line — an olet is faster and more economical than a reducing tee: the run stays uncut and one weld gives a reinforced outlet. Materials: forged carbon steel A105N, A350 LF2 for low temperature, A182 F304/F316 for stainless. Delivered with 3.1 certificates.
Frequently Asked Questions
Weldolet vs sockolet vs threadolet — what is the difference?+
The branch pipe connection: a weldolet is butt-welded (larger branches); a sockolet is socket-welded and a threadolet threaded (both typically for branches below 2").
When is an olet preferred over a reducing tee?+
When the branch is much smaller than the run (e.g. a 1" outlet on an 8" line): the run pipe stays uncut and a single weld gives a reinforced outlet, whereas a tee needs two run welds.
What are elbolets and latrolets for?+
A latrolet takes a 45° lateral branch off the run; an elbolet sits on the back of an elbow, usually for drain, vent or instrument connections.
Which standards cover olet fittings?+
Dimensions per MSS SP-97; branch end details per ASME B16.11 (socket/threaded) or B16.25 (weld bevel); system design follows the ASME B31.1/B31.3 piping codes.
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