Is There a Shortage of Large Pit Carburizing Capacity in North America?
In early 2024 “The Monty Heat Treat News” published an article entitled “Metlab HT Closing Giving Gear Suppliers “Headaches” -fast forward to 2026 and that closing still has gear suppliers reaching for the aspirin bottle. “Metlab Heat Treat” in Wyndmoor, PA, USA at the time had the largest commercially available pit carburizing furnaces in North America and because of this they drew customers from as far away as Mexico and Canada. For some reason this capacity has never been replaced and to this day “The Monty” still fields inquiries from gear manufacturers from all over North America looking for a carburizing source for large gears and shafts.
Our most recent inquiry came from a manufacturer looking for a commercially available heat-treating source in the Chicago area who could carburize parts12′ long X 38″ diameter with a weight of roughly 14,000 pounds. Our search turned up several possibilities in the area but none had the combination of length and diameter required;
“Hi-Hard Rolls” , Harvey, IL , parts up to 37″ diameter X 150″ long.
“General Surface Hardening”, Chicago, IL. Large pit carburizing furnace.
“Overton Gear” , Chicago, IL. Up to 80″ diameter X 100″ deep, 20,000 pounds
“Flame Metals Processing Corporation”, Rogers, MN 72″ diameter X 76″ deep.
At the end of the day the customer went with commercial heat treater “Worldwide Heat Treat”, in Houston, Texas who as far as we can tell has the largest commercially available pit carburizing furnaces in North America with several pit furnaces, the largest having working dimensions of 100″ diameter X 144″ deep and capable of 60,000 pound loads. It’s interesting that there is such a difference between North America and Europe when it comes to large component carburizing capabilities. We at “The Monty” put this down to the fact that pit furnaces are far more common in Europe than North America and also the presence of so many ‘windmill” manufacturers in Europe which require enormous gears. This has encouraged commercial heat treaters to install furnaces capable of handling these components.
Two European examples include “Carburizing of Large Gears-“Haerterei Reese” in Germany and “Dominial Heat Treatment-The Interview” in the Netherlands-both of whom can handle parts anywhere up to 100,000 pounds. Whether their is enough large gear heat treating requirements in North America to justify the enormous expense of installing a pit furnace capable of handling 100,000 pound parts is debatable but when some North American gear suppliers are forced to source their heat treating requirements to Europe it certainly suggests there is a business case to be made for this investment.
