Home » Blogs » Industrial Heating Experts Speak Blog
The 2007 Edition of NFPA 86 (Standard for Ovens and Furnaces) defines a Class C Furnace as one that “has a potential hazard due to a flammable or other special atmosphere being used for treatment of material in process.”
The pros and cons of government assistance to industry have been debated forever. In the words of Thomas Jefferson, a wise government is one that shall leave men “free to regulate their own pursuits of industry and improvement, and shall not take from the mouth of labor the bread it has earned.”
People have been aware of and worked iron for approximately 4,000 years. However, its usage only became recognized around 1200 BC. This is because it was extremely difficult to smelt, melt, cast or forge because of temperature required.
Among the 2007 collection of published articles from the Journal of the Air and Waste Management Association (JAWMA) was one from the University of California, Davis on emissions from stainless- and mild-steel welding. Using new experimental techniques, the group confirmed (approximately) the EPA’s prior AP-42 data for hexavalent chrome, Cr(VI), emissions from stick and gas welding (using ~18% chromium electrodes) to be approximately 0.2 and 0.02 g Cr(VI)/kg of electrode, respectively, and found Cr(VI) to be undetectable during welding of mild steel (with chrome-free electrodes).
The reason for the metallurgical heat-treatment process of stress relieving is primarily to remove residual, induced stresses from the steel. These stresses will occur as a result of rolling, forging, machining, welding, etc.
Distortion is caused by stresses in a part that are relieved during thermal treatment. These stresses include induced machining stresses from variations in the machining procedure and stresses caused by non-metallic inclusions due to differential rates of expansion.
Most Industrial Heating readers are familiar with the U.S. Patent and Trademark Office (USPTO) and its role in protecting the intellectual property (IP) of business enterprise. Patents are a significant financial investment for most companies, so innovations are typically not patented unless a substantial financial benefit is anticipated.
Check out the February 2020 issue of Industrial Heating, featuring an editorial on Nonferrous – Products and Their Processes, along with the Inspection and Maintenance Critical to Safe Fuel-Train Operation.