Innovations in Friction Welding: Improving Production, Driving Quality & Cost Effective Solutions

Interview conducted by Kris WalkerJul 3 2013

Innovations in Friction Welding benefit a host of industries. Seeking new ways of improving production, focusing on driving quality for cost effective solutions; David Hoel from American Friction Welding, Inc. talks to AZoM about the latest developments within Friction Welding and how a variety of industries are staying ahead of the curve with the latest technology.

For people who have little awareness of new types of friction welding capabilities can you explain what Linear Friction Welding is? And why AFW is exploring the idea of adding this capability to the manufacturing floor?

American Friction Welding Inc., known in short as AFW, specializes in Direct Drive Rotary Friction Welding. An area of expansion for us may be the new technology of Linear Friction Welding. This allows the creation of asymmetric near-net shapes in an additive process where the part geometry is built up from smaller “building blocks”.

This eliminates the cutaway waste of expensive alloys. Sectors like aerospace will reap big improvements in material usage efficiency. We are seeking clients interested in applying this technology and will partner with them to develop prototypes with the intention of bringing Linear Friction Welding into mainstream manufacturing.

It states on your website that Linear Friction Welding can play a role in expanding the number of ways that custom bonding needs can be fulfilled. How does this process play a key role?

In addition to creating near-net shapes for maximum efficiency, we can improve product and reduce costs. For example, machine components with extreme wear exposure are often made from expensive carbide alloys. In these cases, the component could be from common carbon steel. We can then use Linear Friction Welding to bond strips of tungsten carbide to the wear surfaces to improve part life and reduce material expense.

In 2011, AFW provided quality friction welding and ‘turn-key’ products to customer specifications. Your main Industry demographic in 2011 was the oil and gas industry. Has this changed somewhat in 2013? Have there been any new industries that AFW has gone into?

The Oil and Gas industry remains a key sector at AFW. We also see growth in automotive components, pump shafts, and pump impellers. Production of electric motor shafts seems to be picking up domestically as well.

Having expanded your capabilities at AFW in 2012, what have been the benefits as a result of the expansion?

AFW focuses on listening to our customers to provide effective solutions that help them succeed in their businesses. For example; we added in-house production of honed hydraulic cylinders to streamline the process of friction welding forged caps onto the cylinders. A bottle neck was occurring in the supply chain around incoming cylinders. By adding capacity to make the honed cylinders, we removed a supply chain limitation for our customer.

A new friction welding machine with orientation capabilities also came online this year. By orientation, we mean that a feature on one sub-component can be aligned with features on the opposite sub-component during the friction welding process. This is a special accomplishment, because the rotating part must be stopped in exact alignment with its starting point.

This is done using a high RPM chuck under the intense forge pressure necessary to create a friction weld bond. We can accomplish end-to-end orientation to within less than one degree. Uniquely formed parts may be created this way to eliminate the need for elaborate machining efforts.

Steering linkage side ports alligned with orientation capabilities.

Another exciting new capability is found in our Automated Micro-Friction Welder. This machine was commissioned to solve a customer’s need for high-volume production. It can bond parts as small as 1/16” diameter.

We will introduce this capability to companies in industrial sectors like medical equipment and electronics. We have developed a bi-metal coupler comprised of aluminum tubing fused to copper tubing with this equipment. This coupler will have applications in electronics and industries that handle specialty compressed gasses and fluids.

Section view of bi-metal Aluminum-Copper tubes.

You state, on your website, the benefits of friction welding and go into detail about the three stage friction welding process. Can you go into more detail about the three stage process? And does it pose a consistent balance in quality and cost effective solutions, as compared with other methods of welding?

Friction Welding is a computer controlled process that insures identical results. Parameters are developed for each unique part and saved for repetitive use. It is critical to consistently use material chemistry, size, and part configuration for subsequent welds that match the conditions used to develop the weld parameter. AFW relies on material certifications to assure that those material conditions are met, and then applies the assigned parameters to join parts. Friction Welding uses only the material of the parts themselves to create a bond.

It is a full strength, full penetration bond that occurs across the entire weld face resulting in a molecular fusion of the two components. No added materials, gasses, or chemicals are introduced into the weld joint as found in other methods. The joint is stronger than conventional welding and the entire weld zone equals or exceeds the strength of the parent material. In fact, the weld zone itself can be machined as if it were original, solid parent material.

The weld zone is free from contamination and voids. The quality is measurable and repeatable owing to the computer control with more reliability than a hand applied method. In production lot sizes of 100 or more pieces the process is exceptionally cost effective due to its repeatability.

Image Credits: American Friction Welding

Can you tell us about upcoming plans? What can we expect from AFW in the future?

There is an opportunity to configure ourselves as long-term agreement, sub-contract manufacturers to OEMs in several sectors. Historically, AFW has operated as a job shop that handles custom orders along with overflow work during maintenance breaks and peak demand at OEMs. There are now several dedicated, high-volume cells running in our plant specific to certain part types.

We will expand on that concept and configure ourselves to become high-volume, wholesale providers of components in sectors like truck axles, hydraulic piston rods, pump shafts, and electric motor shafts. These are areas that are well known consumers of friction welded components, and I believe that AFW will make an excellent partner in providing these components to OEM assembly plants.

About David Hoel

David Hoel is the New Business Development manager at AFW. He has spent his career in business to business sales with an emphasis on technical products. He joined the team at American Friction Welding, Inc. in June 2011.

Friction Welding provides an especially creative outlet for his interests, because an educational approach is necessary for sharing the concept. Few people in industry are familiar with the process, so most discussions start with shared learning. Friction Welding can be of incredible value wherever metal components of contrasting sizes, dissimilar chemistry, or unusual shapes must be joined together with maximum strength.