Socket Weld Fittings insert the pipe diagonally into the groove of the fitting and seal the connection using an angle weld, is a key component in piping systems for small-diameter pipe connections. How are socket weld fittings properly sized? Which of the different materials of socket weld fittings is better? Keep reading to help you learn more about this information and knowledge.
Socket Weld Fittings
Basic Performance and Size Chart
- Scope of application: Piping systems with nominal diameters ≤ NPS 2
- Application scope: chemical industry, energy, ships and other fields.
- Material: carbon steel: Q235, A105; stainless steel: 304, 316L, 321; alloy steel: 15CrMo, nickel-based alloys, etc.
- Standard: Comply with ASME B16.11.
- Advantage: high sealing, strong structure
Comprehensive Table of Core Dimension Parameters for Socket Weld Fittings in ASME B16.11 and GB/T14383-2021 Standards
| Parameter/Specification | DN15 (1/2″) | DN20 (3/4″) | DN25 (1″) | DN50 (2″) | Notes |
| Socket Depth (Jmin) | 21.9mm | 24.1mm | 26.4mm | 31.8mm | Minimum value, actual value must be ≥ standard value |
| Socket OD (Bmin) | 22.2mm (3000LB) | 27.7mm (3000LB) | 34.5mm (3000LB) | 51.7mm (3000LB) | OD increases with pressure rating (e.g. 6000LB DN50 Bmin≥53.1mm) |
| Bore Diameter (Dmin) | 14.2mm | 19.3mm | 25.4mm | 42.1mm | Must match pipe wall thickness (e.g. Sch80 DN25 Dmin≥23.8mm) |
| Wall Thickness (Cmin) | 3.7mm (Sch40) | 4.2mm (Sch40) | 5.2mm (Sch80) | 6.0mm (Sch80) | SS material thickness can be reduced by 10%-15% |
| Facing Type | RF/FF/MF/TG/OSG/RJ | RF/FF/MF/TG/OSG/RJ | RF/FF/MF/TG/OSG/RJ | RF/FF/MF/TG/OSG/RJ | RF most common, RJ for high pressure applications |
| Concentricity Tolerance | ≤0.5mm | ≤0.6mm | ≤0.7mm | ≤0.8mm | CS fittings require normalizing to maintain tolerance |
| Applicable Standard | ASME B16.11/GB14383 | ASME B16.11/GB14383 | ASME B16.11/GB14383 | ASME B16.11/GB14383 | GB/T14383-2021 adds internal/external threaded elbow types |
Types of Socket Weld Fittings
Bends
There are a variety of elbows such as 90° elbow and 45° elbow, which can change the direction of the pipeline, and the design of the elbow can reduce the space occupied by the pipeline and make the pipeline system more rationalized.
Tee
Divided into equal diameter tee and reducer tee, to realize the pipeline diversion and merging. It is usually applied to the scene of multi-fluid control.
socket weld cross
Divided into equal and opposite diameter crosses, used for diverting and combining the flow of pipelines.
socket weld coupling
Socket Weld Coupling is a kind of forged pipe fittings connecting pipelines by socket welding, which is suitable for small diameter (usually ≤NPS 2/DN50) high-pressure system with high sealing, structural strength and flexibility of adaptation.
American socket weld boss
Connects branch pipes vertically to the main pipe, providing a high-strength, low-risk leakage branch connection for high-pressure fluid distribution systems.
cap
socket weld cap used to seal pipe ends or branch connections for NPS 1/8″~4″ small diameter high pressure piping systems in accordance with ASME B16.11.
45° Y-branch
For connecting branches at a 45° angle to the main line to divert or merge fluids, suitable for high pressure, small diameter piping systems.
How To Correctly Describe The Socket Weld Fittings Dimensions
Accurately expressing the size of Socket Weld pipe fittings is a central step in ensuring that your piping system and fittings are compatible.
Socket weld fittings with unsuitable specification size will lead to no way to install the pipe, and it can’t run smoothly in serious cases, which will lead to the occurrence of safety accidents. Therefore, the dimensions of socket weld fittings need to be clearly grasped at the time of procurement and design.
- Outside Diameter (Outside Diameter, OD): The outside diameter of socket weld fittings is an important parameter that describes the size of the fittings. socket weld fittings are usually manufactured in accordance with ASME B16.11 or ASTM A234. socket weld fittings are required by the standards. The Socket Weld Fitting Standard requires that outside diameters be expressed in millimeters (mm) or inches (inch). For example, a 2-inch OD carbon steel pipe would require a SW elbow with the same OD specification. A pipe with a nominal outside diameter of 2 1/2 inches requires a Class 3000 45-Deg Elbow Socket Weld Fitting Pipe with the same outside diameter specification.
- Pressure Class: Socket weld fittings pressure class is generally divided into Class 3000, Class 6000, Class 9000, and the choice of pressure class and female thread to socket weld fittings and other connectors to keep matching.
- Wall thickness (Schedule): Use “Schedule (e.g. SCH10, SCH40, SCH80) for labeling. High-pressure steam piping systems require fittings with SCH80 or higher wall thicknesses. For normal industrial water piping, SCH40 is sufficient.
Socket Weld Fittings Carbon Steel Pipe
- Carbon Steel Socket Weld Fittings: Carbon Steel Socket Weld Fittings are the most commonly used material for industrial applications. Carbon Steel Socket Weld Fittings are available in a wide range of sizes including, but not limited to, Socket Weld 45° Elbow, Socket Weld 90° Elbow, Carbon Steel Socket Weld Tee, Carbon Steel Socket Weld Flange, Carbon Steel Socket Weld Reducer, and other types with a variety of functions and shapes. Socket Weld fittings have excellent tensile strength and can withstand high temperature and pressure environments. Good weldability makes them ideal for pipe systems with socket weld connections. They are economical, low cost and suitable for large areas.
- Stainless Steel Socket Weld Fittings: Beautiful appearance, corrosion resistance.
- Alloy Steel Socket Weld Fittings: Wear-resistant and oxidation-resistant.
- Other special materials: Covering Duplex Steel, titanium alloy and nickel alloy and other special materials.
