Fittings / CPL
Coupling
Used to join two pipes of the same diameter together.
Technical Specifications
Key Features
- Quick installation
- Cost-effective solution
- Compact design
- High sealing performance
- Standard sizes
- Easy fabrication
Applications
- Pipe extension
- Repair joints
- Small-diameter lines
- Plumbing systems
- Ventilation lines
- Instrumentation connections
Dimension Table
| Size | Outside Diameter (mm) | Thickness (mm) | Length (mm) | Thread |
|---|---|---|---|---|
| 1/2" | 21.3 | 3.73 | 35 | NPT |
| 3/4" | 26.7 | 3.91 | 38 | NPT |
| 1" | 33.4 | 4.55 | 41 | NPT |
| 1-1/2" | 48.3 | 5.08 | 48 | NPT |
| 2" | 60.3 | 5.54 | 54 | NPT |
| 3" | 88.9 | 7.14 | 64 | NPT |
Technical Notes
- 01Available in full and half coupling types.
- 02Use thread sealant for threaded couplings.
- 03Socket weld couplings preferred in high-pressure systems.
What are pipe fittings?
Pipe fittings are the components that change direction, branch, reduce or terminate a pipeline: elbows (90°/45°), tees, reducers, caps and crosses. Butt-weld fittings are produced to ASTM A234 / EN 10253 material specs and ASME B16.9 dimensions, in sizes from 1/2" to 48".
Elbow types and connection methods
The most used fitting is the elbow: made in 90° and 45° angles, long radius (LR, radius = 1.5 × diameter) and short radius (SR, radius = 1 × diameter). LR elbows are standard because they give lower pressure drop and turbulence; SR elbows serve tight layouts. By connection method there are three families: butt-weld (ASME B16.9 — larger bores), socket-weld and threaded (ASME B16.11 — typically below 2"). The material range covers carbon steel (A234 WPB), alloy (WP11/WP22/WP91), stainless (A403) and low-temperature (A420) grades. All products ship with 3.1 certificates and full traceability.
Frequently Asked Questions
What does ASTM A234 WPB mean?+
A234 is the material spec for wrought carbon and alloy steel fittings for moderate and elevated temperature service; WPB is the most common carbon steel grade (W=weldable, P=pressure, B=grade B).
Long radius (LR) vs short radius (SR) elbow?+
An LR elbow has a bend radius of 1.5 × diameter, an SR elbow 1 × diameter. LR gives less pressure drop and erosion; SR is chosen only where space is tight.
Where are butt-weld, socket-weld and threaded fittings used?+
Butt-weld (B16.9) on larger-bore main lines; socket-weld and threaded (B16.11) typically below 2", on small-bore, instrument and utility lines.
How do EN 10253 and ASME B16.9 relate?+
Both are butt-weld fitting standards: B16.9 is the American system, EN 10253 the European one. The project specification determines which system sets dimensions and materials.
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