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Understanding Pipe Ends: A Comprehensive Guide

Cold bending of bending pipes

In the intricate world of piping systems, meticulous attention to detail is paramount to ensure seamless operation and longevity. While factors like size and material are crucial considerations, the significance of pipe ends cannot be overstated. Understanding the various types of pipe ends and their applications is essential for achieving a proper fit, maintaining a tight seal, and optimizing overall performance.

Rotary Draw Bending
Stretch Forming


While size is an important factor when choosing flanges, elbows, and other components of your piping process, pipe ends are a critical consideration to ensure a proper fit, a tight seal, and optimal performance.


The type of pipe end chosen will determine how it connects to other components and which applications and components the pipe is best suited for. Pipe ends typically fall into one of four categories:

  • Plain Ends (PE)
  • Threaded Ends (TE)
  • Beveled Ends (BW)
  • Grooved Mechanical Joints or Grooved Ends

A single pipe can also have multiple end types. This is often designated in the pipe description or label. For example, a 3/4-inch SMLS Schedule 80s A/SA312-TP316L TOE pipe has threads on one end (TOE) and is plain on the other. In contrast, a 3/4-inch SMLS Schedule 80s A/SA312-TP316L TBE pipe has threads on both ends (TBE).


PE pipes feature ends typically cut at a 90-degree angle to the pipe run for a flat, even termination. In most cases, plain end pipes are used in combination with slip-on flanges and socket weld fittings and flanges. Both styles require fillet welding on either one or both sides of the fitting or flange and at the base of the fitting or flange. Where applicable, the plain end will be placed typically ⅛” from where the pipe rests to allow for thermal expansion during welding. This makes them ideal for small diameter piping systems.


Typically used for pipes with a nominal size of three-inch or smaller, TE pipes allow for an excellent seal. Most pipes use the National Pipe Thread (NPT) standard which describes the tapered threads used on the pipe with the most common taper measuring 3/4-inch per foot. This taper allows the threads to pull tight and create a more effective seal. However, connecting the threads on a TE pipe properly is essential to avoid damaging pipes, fittings, or flanges. Improper assembly or disassembly may lead to galling or seizing. Once unseized, damage to the threads or pipe could further reduce corrosion resistance and hygienic properties — two popular reasons for choosing stainless steel pipe. Fortunately, avoiding these concerns is often as simple as preparing the threads before assembly.


Used with buttwelding, BW pipe fittings commonly feature a 37.5-degree bevel.

These bevels are often applied by fabricators by hand or through automated processes to ensure consistency.

This allows for a perfect match with BW pipe fittings and flanges and easier welding.


Grooved mechanical joints or grooved end pipes use a formed or machined groove at the end of the pipe to seat a gasket.

Housing around the gasket is then tightened to secure the connection and ensure optimal seal and performance.

The design allows for easier disassembly with a reduced risk of damaging piping components.


Pipe end connections typically used for pipe nipples — are often denoted using abbreviations.

In most cases, the first letter denotes the type of end users while the following letters let you know which ends are finished.

Common abbreviations include:

  1. BE: Bevel End
  2. BBE: Bevel Both Ends
  3. BLE: Bevel Large End
  4. BOE: Bevel One End
  5. BSE: Bevel Small End
  6. BW: Buttweld End
  7. PE: Plain End
  8. PBE: Plain Both Ends
  9. POE: Plain One End
  10. TE: Thread End
  11. TBE: Thread Both Ends
  12. TLE: Thread Large End
  13. TOE: Thread One End
  14. TSE: Thread Small End

If you’d like to know more about common pipe end standards, you can find information from ASME below:

  • ASME B1.1 – Unified Inch Screw Threads
  • ASME B16.25 – Buttwelding Ends


In conclusion, the selection of pipe ends plays a pivotal role in the success of piping systems across diverse industries. Whether it’s the versatility of plain ends, the reliability of threaded ends, the precision of beveled ends, or the convenience of grooved mechanical joints, each type offers unique advantages tailored to specific requirements. By adhering to industry standards and best practices outlined by organizations like ASME, professionals can ensure the integrity and efficiency of their piping systems. With a comprehensive understanding of pipe ends and their applications, stakeholders can navigate the complexities of piping projects with confidence and precision.

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