Threaded pipe fittings are not the same as socket weld pipe fittings. They are two distinct types of fittings used for different types of connections.

Threaded pipe fitting

A threaded pipe fitting is a type of pipe fitting that has threaded ends, allowing it to be connected to other fittings or pipes by screwing them together. Threaded fittings typically have male threads on the exterior of the fitting that mate with female threads on the pipe or other fittings.

Threaded pipe fittings are commonly used for smaller pipe sizes, typically up to 4 inches in diameter. They are often used in low-pressure applications, such as residential plumbing, irrigation systems, and certain industrial processes.

These fittings are available in various shapes and configurations to accommodate different piping needs. Some common types of threaded fittings include elbows, tees, couplings, unions, caps, and plugs. These fittings can be made from a variety of materials, including metals like stainless steel, brass, or carbon steel, as well as non-metallic materials like PVC (polyvinyl chloride) or CPVC (chlorinated polyvinyl chloride).

When installing threaded fittings, it's important to ensure a proper seal to prevent leaks. This is typically achieved by applying thread sealants or using PTFE (polytetrafluoroethylene) tape on the male threads before connecting the fittings. These sealants help fill any gaps between the threads and create a tight and leak-free joint.

Threaded fittings offer several advantages, including ease of installation, versatility, and the ability to disassemble and reassemble the connections when needed for maintenance or repairs. However, they may not be suitable for high-pressure applications or systems that require exceptionally tight seals, as threaded connections can be prone to gradual loosening over time.

It's important to follow proper installation practices, such as using appropriate thread sealants, tightening the fittings to the recommended torque, and ensuring proper alignment to achieve reliable and leak-free connections with threaded pipe fittings.

BS standard plastic pipe fittings female threaded pvc reducing coupling F/F

ISO1452 Pressure Pipe Fittings PVC Female Threaded Straight Tee inserted brass

SCH40 ASTM D2466 PVC 90 Degree Female Threaded Reduced Elbows Long

Socket weld pipe fitting

A socket weld pipe fitting is a type of pipe fitting that is used for connecting pipes by inserting the pipe into a recessed area (socket) of the fitting and then welding the pipe to the fitting. The joint is made by welding the pipe to the fitting from the outside.

Socket weld fittings are commonly used for larger pipe sizes and in high-pressure applications, such as in industrial piping systems, oil and gas pipelines, and chemical plants. They provide a strong and permanent connection that is resistant to leakage and vibration.

The socket weld fitting has a socket or internal recess that allows for the insertion of the pipe end. The pipe is inserted into the socket, and then the joint is welded using a fillet weld around the outer circumference of the fitting where it meets the pipe. This welding process creates a robust and reliable joint that can withstand high pressures and temperatures.

Socket weld fittings are available in various configurations to suit different piping needs, including elbows, tees, crosses, couplings, unions, and reducers. They can be made from materials like carbon steel, stainless steel, alloy steel, or other metals suitable for welding.

It's important to note that socket weld fittings require welding skills and equipment for proper installation. The welding process involves using appropriate welding techniques, such as shielded metal arc welding (SMAW) or gas tungsten arc welding (GTAW), to create a strong and secure weld joint. Professional assistance or qualified welders are often required for socket weld installations to ensure the welding is done correctly and meets industry standards.

Socket weld fittings offer several advantages, including high strength, durability, and resistance to leakage. They are commonly used in applications where a reliable and permanent joint is required, particularly in high-pressure and high-temperature systems. However, they are not easily disassembled, so socket weld connections are considered more permanent compared to threaded connections.

Proper welding procedures, adherence to applicable codes and standards, and regular inspection and maintenance are important for ensuring the integrity and performance of socket weld pipe fittings.

Threaded pipe fitting vs Socket weld pipe fitting

The main difference between threaded and socket weld pipe fittings lies in their method of connection. Here's a breakdown of the two types:

Threaded Pipe Fittings:

Threaded pipe fittings, as the name suggests, have threads on their interior or exterior surfaces, allowing them to be connected by screwing them together.

They typically have male threads on the exterior of the fitting that mate with female threads on the pipe or other fittings.

Threaded fittings are commonly used for smaller pipe sizes (usually up to 4 inches) and in low-pressure applications.

They are relatively easy to install and disassemble, making them convenient for maintenance and repairs.

Threaded connections may require the use of thread sealants or tape to ensure a tight and leak-free joint.

Socket Weld Pipe Fittings:

Socket weld pipe fittings involve inserting the pipe into the fitting's socket or recessed area and then welding the pipe to the fitting.

The socket weld fittings have a socket or internal recess that allows for the insertion of the pipe end.

The joint is then welded from the outside of the fitting to secure the connection.

Socket weld fittings are commonly used for larger pipe sizes and in high-pressure applications.

They offer excellent strength and leak resistance, making them suitable for critical and demanding systems.

Socket weld connections require welding skills and equipment, making the installation process more involved and potentially requiring professional assistance.

In summary, threaded fittings use threads to create a mechanical connection, while socket weld fittings involve welding the pipe to the fitting for a strong and permanent joint. The choice between the two depends on factors such as pipe size, pressure requirements, ease of installation, and the need for disassembly or maintenance.