Beveling and Threading: What End Finishes Do You Offer for Seamless Pipes?

Introduction: The Critical Connection Point

The seamless pipe's purpose is defined by its ability to connect to other items—valves, fittings, other pipes—to complete a sealed and safe system. Therefore, the connection made to the pipe is not a detail to be considered only in passing, but one that determines how the connection is made in a critical, specification-like way.

The type of end finish you choose is fully dependent on the connection method desired in the project. The joining method is usually determined by variables such as pressure, temperature, and disassembly plans. This guide will describe the three main end finishes we offer on seamless pipe: plain ends, beveled ends, and threaded ends.

1. Plain Ends (PE)

• Description: A plain end pipe is one that has been cut square to the length of the pipe at a 90-degree angle. Edges are typically deburred to eliminate any sharp chips, but there is no other machining on the pipe.
• Application: Plain end pipes are mainly used for small diameter piping systems that will be connected using socket weld fittings, or slip-on flanges. In these cases, the pipe is inserted into the recess of the fitting prior to welding, making a beveled end unnecessary. Plain end pipes are also typical for low pressure structural applications.

2. Beveled Ends (BE): The Standard for Butt Welding

A beveled end is the most common type of end finish for pipes that will be joined by butt welding.

• Description:The end of the pipe is machined to create a specific angled surface. This is done to create a "V" shaped groove between two adjoining pipes, which can then be filled with weld material to form a strong, continuous joint.
• The Quantitative Specification (ASME B16.25):The geometry of the bevel is strictly defined by industry standards to ensure consistent and reliable welds. The most common standard is:
  • Bevel Angle:30° (+5° / -0°)
  • Root Face (or Land):6 mm ± 0.8 mm (1/16" ± 1/32")
  • This precise preparation allows for full penetration of the weld, creating a joint that is as strong as the pipe itself.
• Application:Beveled ends are the standard requirement for virtually all high-pressure, high-temperature pipeline systems in the oil & gas, power generation, and chemical industries where butt welding is the mandated joining method.

A beveled end serves as the most prevalent format of end preparation for pipes that will be permanentlly attached by butt welding.

• Description: The end of the pipe is machined to develop a specific angled surface that creates a "V" shape groove when two adjoining pipes are assembled, which can be fused with weld material to form a strong, continuous joint.
• The Quantitative Specification (ASME B16.25): The geometry of the bevel is specifically defined by industry standards, guaranteeing quality of the welds when properly manufactured. The most common standard is:
  • Bevel Angle: 30° (+ 5° / -0°) Root Face (or Land): 1.6mm ± 0.8mm (1/16" ± 1/32").
  • This degree of preparation allows for full penetration of the weld, and creates a joint that is as strong as the pipe.
• Application: Beveled ends are the standard requirement for almost every high-pressure, high-temperature piping systems in the oil & gas, power generation, and chemical industries where butt welding is the required joining method.

3. Threaded Ends (TE)

• Description: A threaded end secures the pipe's end with tapered grooves to mate with a corresponding threaded fitting, valve, or another pipe. The threads are typically protected for shipping with a plastic cap, and a coupling is usually provided on one end.
• The Standard (NPT): The most prominent standard for threaded pipe in North America is NPT (National Pipe Thread), defined by the ASME B1.20.1 standard.
• Application: Threaded ends are typically used in lower pressure applications and smaller diameter pipes (typically under 4 inches). Examples include utility piping (water, air), fire protection sprinkler systems, and some industrial plumbing applications. The advantage to these applications is the ability to unscrew and reassemble the piping system. Threaded ends are generally not appropriate for use in high-pressure or high-temperature service because of the potential for leaks.

Conclusion: Specifying the Right Connection

The choice of end finish is a critical part of a seamless pipe specification. Plain ends are for socket-weld systems, threaded ends are for lower-pressure screwed systems, and beveled ends are the industry standard for high-performance butt-welded pipelines. By clearly specifying the required end finish (PE, BE, or TE) based on your project's connection design, you ensure full compatibility and system integrity from the start.