In this episode of the Dust Safety Science Podcast, Hector Maggi, Managing Director of TFT-Pneumatic, based out of Houston, Texas, discusses the design and use of non-sparking tools in hazardous areas. While explaining how they work and what their primary applications are, he answers the following questions:
- What is a non-sparking tool?
- What applications are non-sparking tools used in?
- How do these tools stay spark-free?
- Are there any auxiliary features that can also be used?
- How are the non-sparking tools certified?
- What is the price difference between sparking and non-sparking tools?
What is a non-sparking tool?
Hector explained that non-sparking tools do not generate the heat, energy or temperature to create an ignition, making them appropriate for use in hydrocarbon-rich environments and/or dust-explosive environments, depending on the certification for the tool.
He presented the example of a sparkless grinder.
“With a regular grinder, (when) you start grinding down, eventually that part is going to get very, very hot. The part where the grinding disc is touching the surface may be 200 degrees Fahrenheit, or over 100 degrees Celsius. Sparks fly out and the further they fly, the hotter they burn. So if that spark is flying out six meters, 18 feet or so, that spark may generate in excess of 2000 degrees Celsius, which is well over 3000 degrees Fahrenheit.”
With a sparkless grinder, otherwise known as a certified cold work grinder, the temperature will not get hot enough to ignite hazardous areas.
What applications are non-sparking tools used in?
Hector confirmed that these tools can be used for any kind of material removal.
“You have grinding, you also have cutting, so those types of tools are good to be used for cutting off a flange, cutting off bolts.”
He added that they are excellent surface prep tools and can be certified to perform in facilities that generate combustible dust. This includes sugar mills, paper mills, and other sites where the prospect of hot work arouses concern because a permit is required and the site may have to be shut down for days at a time.
“That shutdown by itself is extremely costly,” he explained. You’re not only having the loss of production, but you’re having a loss of income. And a lot of people tend to think, “Well, it’s normal, you have to do that type of work in order to keep the facility operational.” But the reality is that if you’re able to minimize that downtime while still being safe, you’re able to maximize your efficiency.”
Hector recalled one natural gas company that wanted to replace a firewall. It was welded on but would have to be cut off. Shutting it down would have cost millions of dollars, so Hector’s company recommended that they use cold cutting tools to remove the wall and bolt it back on afterwards instead of welding it. This strategy saved the client a lot of money.
“Generally speaking, not requiring a hot work permit is tremendously advantageous,” he pointed out. “Not only on the safety side but also on the efficiency and the cost-savings. It’s actually our best selling point.”
He recounted another incident, this one in a facility in the Gulf of Mexico.
“(They) decided that it was okay to perform a cutting job on a pipe. That pipe previously had hydrocarbons, so they had all their locks and safety measures in place, but somehow one of the contractors decided that it was okay to clear a lock and they removed a tag lock. They opened up a valve while the guys were cutting with a traditional grinder. So the moment that the product hit the sparks, the whole thing ignited. There were multiple people killed.
“Had they been using our tools, the sparkless grinders, they would have realized that there was a large amount of hydrocarbon fuel coming out of the pipe. And sure, there would have been an incident, but not one that would have ignited the source and killed (people).”
How do these tools stay spark-free?
Hector emphasized that the tools are low-speed grinders with a maximum rotating speed of 3000 RPM. They also use a proprietary tungsten-based alloy instead of abrasives and have patented cutting shapes so that the teeth don’t hit the same point or area twice.
“By minimizing friction, we minimize temperature, and by minimizing both of them, we really minimize the possibility of an ignition source.”
They remove material on contact and last much longer than a traditional carbide tip, being capable of 1000 man-hours of continuous work.
Are there any auxiliary features that can keep the tools cooler?
TFT Pneumatic grinders are certified without the use of water. Its cutting systems require a bit of water in the form of a nozzle spray, and it is only used when cutting into pipe.
“By having a little bit of water, what we’re trying to do is to minimize any kind of friction between the material and having that lubrication in place essentially prevents it from happening,” Hector explained. “So we’re taking a very proactive approach, and the chances of it happening are slim. And I mean really, really slim.”
How are the non-sparking tools certified?
Hector admitted that it is difficult to get a certification on this type of machine.
“We were the company that broke through on this instance, close to 20 years ago. And the interesting thing about it is that in the US, there are no mechanical risk ignition considerations in the regulations. So we actually were able to break through in Europe. Europe was the first place that considered mechanical risk ignitions, as a potential ignition source. And that was the way that we were able to get our tools certified, back in the day.”
He explained that all tests were done using stoichiometric values, which are essentially the perfect mixture between air and the combustible substance, in pressure-controlled environments.
“We tested all sorts of different ignitable materials. We tested from natural gas, methane, and acetylene, which is about as volatile as it gets. And in every single case, through a very long and tedious process, we were able to do the material removal: the cutting, grinding, surface preparation. That was many, many years ago. And up to this date, we’re coming up on 20 years, and working daily worldwide, we have never managed to create an ignition.”
What is the price difference between sparking and non-sparking tools?
“An angle grinder will run about a few thousand dollars and a roughly comparable pneumatic grinder may run $1000. So it may be about double the cost of that traditional grinder,” Hector conceded. “But it comes with the added safety of being certified and it’s designed specifically to work on demand. It’s a very tough, heavy-duty industrial tool. Our file may go for $700, $800, $900. It varies depending on the size. The difference, as I mentioned, is that (a regular file) may last for 15 minutes. Ours may last 1000 man hours.”
Conclusion
Although non-sparking tools are a bigger investment, they improve safety levels on the job and even save money in the long run.
“I wouldn’t be able to even guess the cost of shutting down a silo for days at a time, or shutting down a sugar mill,” Hector said. “If you add up the costs of that shutdown, we’re incredibly cheaper. Most of the comments that we get from the customer are along the lines of, “You guys saved us a ton of hours. You guys saved us a ton of work, and you guys saved us hard money.”’
If you would like to discuss further, leave your thoughts in the comments section below. You can also reach Hector Maggi directly:
Email: [email protected], [email protected]
LinkedIn: https://www.linkedin.com/in/hector-maggi-198a1961/
If you have questions about the contents of this or any other podcast episode, you can go to our ‘Questions from the Community’ page and submit a text message or video recording. We will then bring someone on to answer these questions in a future episode.
Resources mentioned
Dust Safety Science
Combustible Dust Incident Database
Dust Safety Science Podcast
Questions from the Community
Dust Safety Academy
Companies
TFT-Pneumatic
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DSS099: Design and Use of Non-Sparking Tools in Hazardous Areas with Hector Maggi
