NITREX INC. – Chicago Operations

(Illinois Corporation)

NITREX INC. – Chicago Operations

1900 Plain Avenue
Aurora, IL 60502

Contact: Tom Cooper or Bill Walter
Tel: +1 630 851 5880
Fax: +1 630 851 0733

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Chicago Operations – Heat treating

Nitrex – Chicago has been in business continuously since 1946. The shop primarily caters to the local manufacturing base within a 75-mile radius, while drawing occasional customers from coast to coast, due to its unique processing abilities in many areas. A relatively large collection of equipment of various sizes and capabilities are in place, and the plant prides itself in detail-oriented customer service.

Equipment & Processes

Our equipment is organized in three groups, as described below, with auxiliary equipment scattered strategically through the plant.


We have six nitriding furnaces, with work-zones ranging from 16”dia x 35” (Ø40cm x 90cm) to 58”dia x 72” (Ø1.5m x 1.8m). The equipment is capable of running the following processes: Nitreg®, Nitreg®-C, Nitreg®-S, ONC®, and Nano-S™. Processing methods are described in detail under “Modern Surface Treatments”.


Our two vacuum furnaces are a smaller 6-bar unit, 24” x 36” x 24” (0.6m x 0.9m x 0.6m), and a large 2-bar, with a work zone of 48” x 72” x 36” (1.2m x 1.8m x 0.9m). We are also in the process of installing a vacuum furnace with an oil quench, which will also be able to perform vacuum carburizing. Various vacuum processing methods are described in our technical pages under “Vacuum Treatments” and “Modern Surface Treatments”.


Five similar atmosphere furnaces, with a 2000 lb (900 kg) load capacity each, are used for carburizing, carbonitriding, conventional quench, and other related processes (“Conventional Heat Treatments”).

Additional Services

Auxiliary Capabilities

The plant offers various supplementary capabilities that are linked with its core processes, such as tempering, cryogenic freezing, sandblasting, straightening. Various forms of annealing, stress relief or precipitation hardening is performed with or without protective atmospheres, as desired by our customers. Some of these techniques are described under “Other Treatments”.


Our lab is staffed with a degreed metallurgist and it is fully equipped for sample preparation and metallographic evaluations.


We have several large trucks on the road every day, with regular routes throughout the Northern Illinois region.


We have maintained ISO and TS approvals in good standing for many years.