Recycling on the Rise: Inspection Efficiency

It’s never been easier to recycle cutting tools, which produces both cost savings and environmental benefits.

Courtesy of All images: Sandvik Coromant

While many individuals see recycling as its own reward, the costs of running a recycling program can sometimes be hard to justify. Recycling cutting tools, however, is an easy way to reduce costs throughout the supply chain while benefiting the manufacturing industry and the environment. And, in recent years, it has become easier for machine shops to participate in tool recycling programs.

Sustainability and Recycling

During the past 20 years, sustainability has grown from a fledgling concept to a philosophy that helps shape the actions of many companies. On the most basic level, sustainability involves using resources in a way that will not negatively impact future generations’ ability to innovate and flourish. Many initiatives related to sustainability revolve around minimizing waste and increasing recycling to offset the effects of consumption.

A Sandvik Coromant display promoting the benefits of cutting tool recycling.

The rapid modernization of enormous emerging markets has made sustainability even more important. India and China together account for about 37 percent of the world’s population. As these countries and others develop, their middle classes will explode and increased standards of living will create tremendous demand for products from nearly every industry. This demand can dramatically affect prices for a broad range of resources.

Cutting tool recycling has various immediate and long-term benefits. Eliminating waste, by definition, reduces consumption of resources and helps companies cut costs. Recycling expands material supply. Also, recycling processes typically require less energy and produce less pollution than those used to create virgin materials, whether through mining or other means of production. This further reduces costs and limits the environmental impact of manufacturing operations.

What’s in Them?

Before making a case for recycling cutting tools, let’s examine the relevant materials. Because of its combination of hardness and toughness, cemented carbide is used to produce 75 percent of inserts and other cutting tools for the global market. First developed in the 1920s, cemented carbide is made up of tungsten carbide and cobalt.

Tungsten ore is subjected to mining, chemical and heating processes to render the naturally occurring mineral into a usable form. China accounts for 79 percent of the production and 33 percent of the consumption of the metal. Worldwide, 58 percent of tungsten is used to produce cemented carbide.

About 80 percent of the world’s cobalt supply is produced as a byproduct of either nickel or copper production operations. Used across a much broader spectrum of applications, only 12 percent of global cobalt consumption is for wear-resistant alloys, including cemented carbide. The amount used in cutting tool production is still significant, though.

Historically, prices for tungsten have remained relatively constant, though that has changed dramatically during the past 6 years. From 2004 to 2008, tungsten prices quadrupled, to about $18 per pound. They dropped to about $11 per pound in December 2008 and in August were about $13 per pound (see tungsten price chart on page 62). Cobalt prices have been volatile for a much longer period, ranging anywhere from $7 per pound to a recent high of $40 per pound. In August, the price of cobalt was about $18 per pound (see cobalt price chart on this page).

Recycling Processes

Two well-established processes account for the vast majority of cemented carbide recycling. In the first, scrap is sorted and cleaned before being combined with zinc in a vacuum furnace. This process breaks down the material to the point where it can be pulverized and up to 98 percent of the powder, composed of tungsten and cobalt, can be reclaimed. Typically, 40 percent of the powder is used in new cutting tools and the remainder is used in products such as wear parts and mining tools.

A chemical process can be used to reclaim elements individually. It requires more energy than the zinc process, but also has a higher recovery output, allowing 100 percent of the recycled material to be used to make new cutting tools. A chemical-process facility is less environmentally friendly because it produces byproduct chemicals that must be safely disposed of. Additionally, a chemical-process facility typically costs twice as much to build and is slightly more expensive to operate than a zinc-process facility.