SOCKOLET

Sockolet MSS SP97

A Sockolet fitting is a type of branch connection used in piping systems to provide an outlet from a larger (main) pipe to a smaller (branch) pipe. Likewise Weldolets, Sockolets are used to make a 90-degree pipe branch. Sockolets may be “size on size” or “reducing”. Sockolet is a member of the O’let family, which includes various fittings designed for different connection needs. The Sockolet is specifically designed for socket weld connections, which distinguishes it from other types of branch fittings, such as Weldolets (designed for butt-weld connections) or Threadolets (designed for threaded connections).

A Sockolet is essentially similar to a Weldolet, with the difference that the branch pipe is connected to the run pipe, via the Olet, with a socket weld connection that shall conform to ASME B16.11.

Fillet welds are used to connect the branch pipe to the branch side of the Sockolet. On the pipe run side, a Sockolet requires a welded connection.

Key advantages of Sockolets:

  • Socket Weld Connection: Sockolets are used to create a 90-degree branch connection and are welded into place via a socket weld. The branch pipe is inserted into the Sockolet’s socket and then welded around the top to secure it. This method provides a strong, leak-proof connection.
  • High-Pressure Applications: Sockolets are well-suited for high-pressure applications where the fluid dynamics require a smooth transition and minimal turbulence at the connection points.
  • Size and Pressure Ratings: They are available in a range of sizes and pressure ratings to match the requirements of various piping systems, ensuring compatibility with the main pipe’s diameter and wall thickness.
  • Material Variability: Like other O’lets, Sockolets are manufactured in various materials, including carbon steel, stainless steel, and alloy steel, to cater to different environmental conditions and fluid types in the piping system.
  • Reduced Stress Concentration: The design of a Sockolet aims to minimize stress concentration at the branch connection, enhancing the overall integrity and longevity of the piping system.

SOCKOLET VS. WELDOLET

Sockolets belong to the “socket fittings” family (forged fittings) and are available in classes 3000#, 6000#, and 9000#, whereas Weldolets are classified as buttweld fittings. Sockolets are used for lower pressure applications, and smaller pipe diameters, than Weldolets.

The key differences between Weldolets and Sockolets are:

Connections Methods

  • Sockolet: Designed for socket weld connections. The branch pipe is inserted into the Sockolet’s socket and then welded around the top. This method is typically used for smaller pipe diameters and provides a smooth and compact connection.
  • Weldolet: Made for butt-weld connections. It is welded onto the side of the main pipe and the end of the branch pipe, allowing for a direct and structurally sound connection. Weldolets are used for a wider range of pipe sizes and can handle significant changes in pipe diameter.

Applications

  • Sockolet: Suited for high-pressure and high-temperature applications where space is limited and a leak-proof connection is essential. The socket weld connection offers excellent strength and is commonly used in smaller bore piping on projects that require a reliable seal.
  • Weldolet: More versatile in application, Weldolets can be used in both high-pressure and low-pressure systems. They are preferred for creating branch connections where the branch size is significant compared to the main pipe. Due to their design, they are better suited for withstanding stress and are often used in industries such as oil and gas, petrochemical, and water treatment.

Sizes

  • Sockolet: Generally used for smaller branch connections, typically up to 2 inches in diameter. They are rated for high-pressure applications, often in alignment with the pressure ratings of the socket weld fittings.
  • Weldolet: Can accommodate a broader range of sizes, from very small to very large diameters, making them suitable for a wider variety of applications. Weldolets can also match the pressure ratings of the main pipe, allowing for their use in both high and low-pressure systems.

Stress Distribution

  • Sockolet: The socket weld connection of a Sockolet minimizes stress concentration, making it suitable for applications where the integrity of the piping system is critical under high pressure.
  • Weldolet: Designed to minimize stress concentrations at the branch connection through its contoured, integrally reinforced design. This makes Weldolets particularly effective in situations where the branch connection might be subjected to thermal or mechanical stress.

Installation Complexity

  • Sockolet: Requires precise fitting and welding inside the socket, which can be more challenging in tight or confined spaces.
  • Weldolet: Installation involves preparing the main pipe surface and executing a butt-weld, which can be more labor-intensive but allows for a more versatile application across different pipe sizes and conditions.

THREDOLET

Threadolet MSS Sp97

A Threadolet is a type of branch fitting that is used to provide an outlet from a larger pipe to a smaller one. Unlike Weldolets and Sockolets, which are designed for welding, Threadolets facilitate connections via threaded fittings. This characteristic makes Threadolets particularly useful in applications where welding is not feasible or where a detachable connection is preferred for maintenance or operational flexibility.

Thredolets are used for low-pressure 90-degree pipe branches. The branch pipe is screwed on the Thredolet, which is welded on the run pipe. The threading is generally of the NPT type and conforms to the ASME B1.20.1 specification.

Thredolets belong to the “threaded fittings” family (forged fittings) and are available in classes 3000# and 6000#.

Threadolets are commonly used in low-pressure piping systems where a removable connection might be necessary, such as for instrumentation ports, pressure gauge connections, and smaller branches from main pipes. They are particularly valued in oil and gas, chemical processing, and petrochemical industries, where their ease of installation and maintenance, as well as their adaptability to various environments, make them an ideal choice.

Key Thredolets features:

  • Threaded Connection: Threadolets are equipped with female threads to accommodate the male threads of the branch pipe. This enables a secure and leak-proof connection without the need for welding.
  • Versatile Applications: Suitable for a wide range of applications, especially in systems where flammable or hazardous materials are present, and hot work (like welding) poses a safety risk.
  • Material Compatibility: Available in various materials to match the piping system, including carbon steel, stainless steel, alloy steel, and more, ensuring compatibility with different fluid types and operational conditions.
  • Pressure Ratings: Threadolets are designed to withstand the pressure demands of the system they are integrated into, with ratings often matching those of standard pipe fittings for consistency and safety.
  • Size Range: They can be used to create branch connections in a broad range of sizes, providing flexibility in designing and retrofitting piping systems.

LATROLET

Latrolet branch connection

A Latrolet fitting is a type of branch connection used within piping systems to create a 45-degree lateral connection from a main pipe to a smaller branch pipe. It is part of the family of O’let fittings, which includes various specialized fittings designed for making branch connections in different configurations. Latrolets are specifically engineered for situations where a 45-degree branch is needed, either for a change in the direction of the flow or to connect auxiliary equipment.

Latrolets are commonly utilized in both new construction and retrofitting projects within the oil and gas, petrochemical, power generation, and water treatment industries. Their design makes them particularly useful for adding instrumentation, vents, drains, or other auxiliary connections at a 45-degree angle, facilitating optimal flow dynamics and accessibility.

Latrolets are available with butt weld connections to meet demanding reinforcement requirements or with socket weld/threaded connections in classes 3000# or 6000#.

Key Features:

  • Angled Branch Connection: The defining feature of a Latrolet is its ability to create a 45-degree branch, which can be crucial for directional changes in piping systems or for integrating lateral connections efficiently.
  • Versatile Connection Types: Latrolets can be manufactured for butt weld, socket weld, or threaded connections, providing flexibility to match the requirements of the piping system and the installation preferences.
  • Range of Sizes and Pressure Ratings: They are available in various sizes and pressure ratings, allowing them to be used in a wide range of applications, from low-pressure residential systems to high-pressure industrial settings.
  • Material Compatibility: Similar to other O’let fittings, Latrolets are made from a variety of materials, including carbon steel, stainless steel, and alloy steel, to ensure compatibility with the main pipe’s material and the operational environment.

ELBOLET

Elbolet fitting

An Elbolet is a specialized type of branch fitting designed to provide an outlet connection on the curvature of an elbow. It is part of the broader family of O’let fittings, which are used to create integrally reinforced branch connections from a larger (main) pipe to a smaller (branch) pipe. The unique feature of an Elbolet is its ability to be installed on the 90-degree or other curved surfaces of elbows, making it an ideal solution for adding branch connections at these points in a piping system.

Elbolets are commonly used in piping systems that require branch connections directly on elbows, such as in oil and gas, chemical processing, power generation, and water treatment facilities. They are particularly valuable in situations where space constraints or specific flow directions necessitate the use of elbows for branch connections, including instrumentation take-offs, vent lines, or sampling ports.

Elbolets are available with butt weld connections or with socket weld/threaded connections in classes 3000# or 6000#.

Key features:
  • Specific Design for Elbows: Elbolets are specifically engineered to fit the contour of pipe elbows, allowing for the creation of branch connections on the elbow’s surface where standard Weldolets or Threadolets might not be suitable.
  • Versatile Applications: They are used in both long and short-radius elbows, adaptable to various piping configurations and applications, ensuring a secure and leak-proof connection.
  • Connection Types: Elbolets can accommodate different types of connections, including butt weld, socket weld, and threaded connections, offering flexibility in how the branch pipe is connected to the main system.
  • Material and Pressure Compatibility: Available in a wide range of materials such as carbon steel, stainless steel, and alloy steel, Elbolets can be selected to match the material specifications of the main piping system. They are also rated for different pressure classes to suit the operational requirements of the system.
  • Size Range: Elbolets are manufactured in various sizes to connect a broad range of branch pipe diameters to the main elbow, facilitating precise control over flow and pressure in the system.

NIPOLET

Nipolet

A Nipolet is a specialized type of branch fitting designed for extended applications, serving as a combination of a nipple and an O’let. This fitting is used to create a branch outlet from a main pipe to a smaller outlet pipe, typically for instrumentation connections, drains, and vents. Nipolets are particularly useful in applications where space is limited or where a conventional O’let fitting might not be the most practical solution.

Nipolets are widely used for creating branch connections in piping systems where direct instrumentation connections, vents, or drains are required. Their compact design makes them particularly advantageous in tight spaces or in applications where a minimal protrusion from the pipe surface is desired. Nipolets offer a reliable and efficient method for integrating auxiliary lines or equipment into existing piping systems without the need for extensive modifications.

Key features:

  • Integrated Nipple Design: The Nipolet incorporates a nipple, or a short piece of pipe with external threading, directly into the O’let fitting. This design simplifies the connection process by eliminating the need for a separate nipple piece, facilitating a direct, threaded connection to the branch pipe or equipment.
  • Versatile Connection Options: Nipolets can be used for both butt weld connections to the main pipe and threaded connections to the branch line, offering flexibility in installation and application.
  • Material and Size Range: Available in a variety of materials, including carbon steel, stainless steel, and alloy steel, Nipolets can be selected to match the piping system’s specifications. They come in a range of sizes to accommodate different pipe diameters and system requirements.
  • High Pressure and Temperature Ratings: Designed to withstand high-pressure and high-temperature environments, Nipolets are suitable for use in demanding industrial applications, including oil and gas, chemical processing, and power generation.

SWEEPOLET

Sweepolet MSS SP97

A Sweepolet is a specialized type of branch fitting designed for creating integrally reinforced branch connections on piping systems, particularly where there is a need for a smooth flow transition. It belongs to the O’let family, which includes various fittings used to connect smaller-diameter branch pipes to larger-diameter main pipes. The distinctive feature of a Sweepolet is its contoured, gradually curved shape that allows for a more gradual flow change from the main pipe into the branch pipe, minimizing turbulence and stress concentration.

Sweepolets are used in piping systems that require a minimized pressure drop and reduced turbulence at branch connections. Their design is particularly advantageous in high-velocity systems or where the fluid has erosive characteristics, as the gradual transition helps to protect the piping material and maintain system integrity. Applications include critical process lines, high-temperature steam services, and other systems where fluid dynamics are a concern.

Key features:

  • Smooth Flow Transition: The curved design of the Sweepolet facilitates a smoother flow of fluid from the main pipe into the branch pipe. This is particularly beneficial in systems where maintaining a laminar flow or reducing flow-induced vibration is critical.
  • Reinforced Branch Connection: Like other O’lets, Sweepolets provide an integrally reinforced connection, ensuring the structural integrity of the branch connection without the need for additional reinforcement pads.
  • Butt-Weld Connection: Sweepolets are typically installed using a butt-weld connection to both the main pipe and the branch pipe, providing a strong and leak-proof joint.
  • Material and Size Range: Available in various materials such as carbon steel, stainless steel, and alloy steel, Sweepolets can be selected to match the piping system’s material specifications. They are manufactured in a range of sizes to accommodate different pipe diameters and system requirements.
  • High Pressure and Temperature Ratings: Designed to withstand the operational demands of high-pressure and high-temperature environments, making them suitable for use in industries such as oil and gas, power generation, and chemical processing.

The welded connection on the run pipe side can be easily inspected with radiographic examination (RX or RT), ultrasounds (UT), and other non-destructive tests.

HOW TO ORDER BRANCH FITTINGS

Suppliers of Weldolets, Thredolets, Sockolets, and other branch fittings need the following information to identify the needed product:

  • Header run pipe size (which is generally expressed as a range of possible sizes, for example, 36-22)
  • Branch pipe size (the NPS of the connecting pipe to the run pipe, for example, 6 inches)
  • Branch pipe schedule (which can be STD, XS, 160, XXS) for buttweld types of connections (rating shall be provided for socket weld and NPT threaded Olets)
  • Style of branch fitting (Weldolet, Thredolet, Nipolet, Sockolet, etc)
  • Material Grade (example A105, A350 LF2, A182 F304)


EXAMPLE: 36-22 | 6 INCH Sch. STD | Weldolet | ASTM A105