In this process, a mandrel—a metal rod or ball—is inserted into the tube while it is being bent, which creates a more precise bend with no wrinkles or kinks. For some applications, it is acceptable to have a wrinkled tube; particularly when the tube just has to function and quality is not a factor. Read More…
Sharpe ProductsNew Berlin, WI | 800-879-4418
Founded in 1990, Sharpe Products is an ISO 9001:2015 certified company specializing in industrial and commercial pipe and tube bending, laser cutting, end-forming or other custom fabrication services. In addition, we offer a robust line of architectural handrail fittings and accessories such as brackets, connectors, disks, end-caps, flanges, newel caps and spheres.$$$
Paumac Tubing, LLC.Marysville, MI | 810-985-9400
Paumac Tubing, LLC provides quality tube bending, end-forming, cutting and welding and works with aluminum, copper and steel. We are a supplier of OEM and Aftermarket Distribution centers. Paumac Tubing provides innovative solutions to our customer’s needs and we are proud to be ISO 9001:2000 certified. Products offered include: commercial tubes, exhaust tubes and structural components.$$$
LaFarge & Egge, Inc.Lynnwood, WA | 425-778-4123
LaFarge & Egge provides high quality precision tube bending and fabrication to 1-1/2" diameter in aluminum, stainless steel, titanium, inconel and steel. Offering flaring, beading, pressure testing, internal swaged fittings and cyro fitting installation. Tubular parts fabricated exactly how you need them.$$$
Lincoln IndustriesLincoln, NE | 402-475-3671
Lincoln Industries has been designing and manufacturing tube fabrications since 1952. Our tube fabrications range in diameter size, from 3/8” to 8”. Products we offer include tube bending, beading, expanding, welding, and forming. We are committed to manufacturing high-quality products that are delivered on time.$$$
Advanced Bending TechnologiesLangley, BC | 800-563-2363
Advanced Bending Technologies is an industry leader in structural bending, pipe bending, low deformation bending and forming of structural steel. We offer a wide range of innovative bending technology with the implementation of new equipment supplying products that are both accurate and unique to industries with architectural applications. Our services result in labor and material cost-savings.$$$
The process of mandrel bending provides a high quality tube because the amount of flow is improved, making the inside diameter of the tube consistent throughout, even at the bend; something that is not possible to do without using a mandrel. Mandrel bending is commonly used in exhaust applications in the automotive industry, pipe applications in the plumbing industry and instrument applications in the musical instrument manufacturing industry because the process improves the look of the bend and also creates a much tighter bend than is possible with empty bending. When the mandrel is inserted into the tube, it has to be strong enough to support the tube so that it won’t be deformed during bending, but also flexible enough to ensure that the tube is still properly bent.
Mandrel bending takes place during the rotary-draw tube-bending process. With rotary-draw bending, a tube’s bend is created by placing the tube around the form of a rotating bend. The tube is attached to the bend form, and as the form moves forward it is designed to bend the tube in the right places, specific to each tube. Mandrel bending occurs during this process by placing a mandrel inside the tube so that as the tube is bent, the mandrel bends with it, which helps keep the tube’s shape from deforming and provides a precise bend, free of kinks.
Mandrels are usually made of an aluminum-bronze alloy or steel. The aluminum-bronze type is used to bend harder materials such as stainless steel or titanium, while steel mandrels are typically used to bend softer materials such as copper or aluminum. There are different types of mandrels that meet various bending needs: common types include plug mandrels, form mandrels and ball mandrels. Plug mandrels are solid rods that are inserted into the tube; this type of mandrel is often used on tubes that have thicker walls, a larger radius and are going to be bent normally.
Form mandrels are similar to plug mandrels in that they are also a solid rod, but the tips of these mandrels are formed to fit a tube’s specific radius; essentially, it is a custom mandrel. Ball mandrels consist of ball bearings—which can be linked or unlinked—being inserted into the tube. These mandrels are used when a precise bend is required in a tube.