As anyone who reads this column knows, The Doctor likes to define heat treating as “the controlled application of time, temperature and atmosphere to produce a predictable change in the internal structure (i.e., microstructure) of a material.”
The reason for this is that, by its very nature, heat treating allows us to vary the properties (mechanical, physical, metallurgical) of a given material. We can make the parts we heat treat stronger, tougher or more corrosion-resistant. In other words, we can optimize their design performance. But one can, if they are not in control, inadvertently do just the opposite. By now, most of us have heard the buzz about Industry 4.0 and are perhaps wondering what it is, how it will impact us and why we should spend our precious resources implementing it in the heat-treat industry. Let’s learn more.
7 Key Considerations
In our day-to-day working lives, most (if not all) of us are faced with meeting production demands around tight manufacturing deadlines in an ever-changing materials climate. So for us, there is an alternate and equally important definition of heat treating: “Getting the job done right, the first time and every time.” To accomplish this goal, we must satisfy what has been referred to as the seven key considerations in heat treating to ensure our success and survival, namely:
- To know, metallurgically, what you want to accomplish
- To be able to predict the outcome of a heat-treatment operation
- To have repeatability built into the process
- To get the most out of the equipment we have and to use state-of-the art heat-treating equipment whenever possible
- To be aware of how changes to our manufacturing operations influence the outcome of a given heat-treatment process or series of processes
- To not compromise on quality
- To know our costs and predict our profitability
Industry 4.0 and the Internet of Things
Industry 4.0 is intended to help us accomplish all of the above. A catchy name coined from the software industry, it is intended to represent the focus on factory automation and data exchange in a manufacturing environment. Recognizing that human beings create many of the issues that prevent true process control and repeatability, there is a need to help them with what they do.
Industry 4.0 tools include things such as a “cyber” interface with physical systems (i.e., where a physical device is monitored or controlled by computer systems integrated with the Internet), the Internet of Things (IoT), cloud-based computing and even cognitive computing (i.e., the simulation of human thought by computer modeling). These systems are starting to dominate all industries (Fig. 1).
Industry 4.0 creates what today we refer to as a “smart factory.” Industry 4.0 is one in which computers and automation are linked with robotics and connected remotely to computer systems equipped with machine-learning algorithms that can learn and control the systems we run with very little input from human operators. This is why in the realm of heat treatment the emphasis is being placed on in-line single-piece product flow (Fig. 2).
While the term IoT is rather new, the notion of attaching various devices (e.g., sensors) to equipment for measurement and data collection has been with us for many years. But these devices were not always compact or reliable. By way of example, a residual-gas analyzer attached to a vacuum furnace was unheard of a dozen years ago but is a practical reality today.
While various applications and solutions using these devices may have been slow to implement up to now, data collection and reporting done through a myriad of devices and platforms is the next big thing. It is being rapidly implemented into the heat-treat industry, as evidenced by programs such as Ipsen’s PdMetrics and SECO/Vacuum Technologies’ SECO/Predictive maintenance tool package, which avoid physical collection of information by a technician.
In addition, the reliability of devices being attached to a heat-treat furnace has improved dramatically. Today’s powerful computers and cloud tools mean that the analysis process is almost instantaneous and allows us to gain insight from the data we collect, which heretofore was a time-consuming and labor-intense process.
Predictive and Preventive Maintenance
A heat-treat maintenance technician who installs and utilizes smart sensors will discover that they help determine the condition of any part of the system or the entire furnace, predict breakdowns (based on mean time between failure) and pinpoint the most cost-effective time and method for maintenance without loss of productivity. That is, Industry 4.0 tools try to predict failure before it occurs using continuous observations and health checks.
A technique of mitigating equipment risk is by performing regularly scheduled maintenance. The schedule is predetermined by forecasting the overall use and normal wear and tear within a given time period. In short, predictive maintenance follows a predict-and-fix model, whereas preventive maintenance follows a repair-and-replace model.
The Factory of the Future
Quite some time ago now, in an Orwellian-style dream The Doctor presented a vision of the factory of the future. It is worth repeating here given its eerie similarity to where we might be headed.
“The dream. The factory floor is shrouded in darkness and strangely silent. The hum of machinery – the music of manufacturing – and the sound of workers scurrying to and fro are missing. The Factory of the Future welcomes you! An order arrives. In a dazzling display, the lights come on, the factory springs to life, and the shop floor becomes a whirlwind of activity as metal is shaped, heat treated and shipped. The factory floor once again becomes dark and still. The cycle continues. Gone are the heat treaters, having been integrated into the automation sequence. The ‘metallurgist on a chip’ makes all the right decisions. Is this a vision of our future or a practical necessity to compete? Perhaps this view is a bit extreme. But what does the future hold? The Heat Treat Doctor dusts off his crystal ball …”
We now fast forward to a factory visit by The Doctor only a month or so removed from the time this article will appear in print. The executive running the company shared, “My goal is to arrive here in the morning with a cup of coffee in hand and be the only employee in the plant.” His implementation of automation, robotics, vision systems, material handling, in-line testing capability and data acquisition/statistical process control was impressive. The reason – the challenge facing U.S. automotive manufacturers to compete in today’s global economy.
Modernization of the heat-treat shop is critical to both our success and survival as an industry. It will not only be expected from us by our customers but soon be demanded by them as well. As such, it is time to embrace these technological changes in all that we do!
- Herring, Daniel H., “Seven Key Considerations in Heat Treating,” white paper, 1992
- Marr, Bernard, “What Everyone Must Know About Industry 4.0,” Forbes, 2016
- Beudert, Roainer, L. Juergensen and J. Weiland, “Understanding Smart Machines: How They Will Shape the Future,” Schneider Electric, white paper, 2016
- Herring, Daniel H., “The Use of Residual-Gas Analyzers as a Vacuum Analysis Tool,” Industrial Heating, Nov. 2014
- “Getting Started with a Predictive Maintenance and Service Program,” Hitachi Systems, 2017
- Herring, Daniel H., “Where Have All the Heat Treaters Gone?,” Heat Treating Progress, Jan./Feb. 2003