What are Miter bends?

Miter bends are not standard fittings, but are custom-made for piping systems by companies with extensive experience and skilled pipefittters.
A miter bend is a pipe bend made from straight pipes by cutting the ends at an angle and welding the beveled (mitered) ends together, which is called an elbow in the world of piping.

Instead of being forged or hot-bent, the miter bend is constructed from multiple segments joined together with miter welds, creating a smooth curve of, for example, a 90° angle.

Miter bends are the economical choice for large diameter, low to medium pressure pipe systems, miters in the water work industry, air ducts, ventilation pipes and slurry lines where purchasing a forged elbow or induction bend would be costly or impractical.

The use of miter bends is often limited to water supply systems; they can be manufactured in a number of sections and are custom⁃made from pipe in various material grades.

In some refineries and petrochemical plants, miter bends are often used in fire suppression water lines and cooling water lines, but their use is limited today.

Preparation and making a miter bend

A miter bend or miter elbow is made by sawing off the ends of the pipe segments at an angle (miter) and then welding them together, usually at angles of 45° and 90°, to form a bend.

There are two types of miter bend: a non-perpendicular bend and a 3D bend. A miter elbow bend is made from miter⁃cut pieces of pipe. The miter pieces, also called gores, have two end gores and two middle gores in a 4⁃piece miter bend.

example 90deg miter
Each end piece is made up of 1 gore (1+4) and each middle piece is made up of two gores ()2+3).

example 45deg miter
Each end piece is made up of 1 gore (1+3) and the middle piece is made up of one gore (2).

Because miter bends are made from the same tube material, they fit precisely onto the pipe and can be produced at any desired angle and radius.

Miter bends can be manufactured from carbon steel, stainless steel, duplex steel, nickel alloys, and various other materials.

Manufacturing according to a custom design regarding miter angle, saw cuts, radius, finishing, weld end preparation, and material is also possible.

Conclusion: Large miter bends are an excellent alternative to other production processes. High pressures must be avoided with these bends, which is self⁃evident with large pipe diameters. However, the production costs of a miter bend should not be underestimated; in addition to the dimensions, weld seam preparation, and material, the production of a miter bend requires many man⁃hours in all cases.