Industrial piping systems seldom run straight. Pipe fabrication is a widely used method of forming metal piping into varying shapes that allow a pipe to round a corner or form a connection with a previously existing pipeline. Pipe bending, especially 3D bends, include shaping a section of pipe into a gentle curve, an angle, a coil or even an irregular shape with multiple curve radii.
Pipe Fabrication Basics
Pipe fabricatio n includes many steps, one of which is pipe bending or forming. Pipe forming is carried out using one of several methods. Cold forming is performed with the metal at ambient air temperature, usually between 50° and 100° Fahrenheit. Hot forming involves heating the metal to temperatures above the point of crystallization. Hot forming requires less energy input to perform the actual bending, but the process of cold forming imparts additional strength to many types of metal. Sections of piping can be bent using rollers and dies in a procedure called pipe rolling. Bending can also be achieved using a single pressure point to bend the pipe around a die. Bending in this manner usually includes the use of a metal mandrel inserted inside the pipe to preserve the internal dimensions. Pipe rolling generally does not require the use of a mandrel. Other steps in pipe fabrication and 3D bends include welding, riveting and application of specialized coatings.
Pipe Fabrication Configurations
A section of pipe can be bent into nearly any shape using pipe rolling and bending procedures. Some applications require only a gradual curvature of the pipe. One method of specifying pipe curvature is to bend the pipe into a curve with a radius that is a multiple of the diameter of the pipe’s cross section. For example, a pipe can be bent into a curve with a radius that is two times, three times or four times the external diameter of the piping. In other cases, conditions necessitate that a pipe must be bent to a specific angle, such as 90°, 120° or 180°. In yet other situations, an irregular shape might be required that must be formed using a series of curves of different radii.
3D Bending Defined
Three-dimensional pipe bending is the method used to bend a pipe into an irregular shape. Three-dimensional bending is generally used to ensure that two different pipe sections can be joined properly or an immovable obstacle can be avoided by the pipeline. Forming a section of pipe into a spiral is another application of three-dimensional pipe bending. Three-dimensional bending can involve the use of several different sets of dies and rollers. While the process may involve more steps than bending a section of pipe within a single plane, bending a pipe into a three-dimensional shape is not inherently complicated.
Practical Applications for Fabricated Piping Systems
The purpose of most pipe fabrication processes is to construct a pipeline that can carry a fluid from one point to another. Fabricated pipeline systems are used in heavy industry, pharmaceutical manufacture, food processing, chemical manufacturing and petroleum transport and refining. Pipelines carry a variety of fluids including petroleum, steam, water, industrial chemicals and food products. Pipe bending is also used for architectural design and structural applications. In these cases, the internal diameter of the pipe is not as important the strength and appearance of the finished product.
Pipe forming and bending, including three-dimensional bending, are important steps in the pipe fabrication process. The bending of metal piping requires a significant energy input, but the finished result has many practical uses in a variety of industries.