Surface® Combustion pioneered the development of endothermic gas to be used as the carrier medium for today’s gas carburizing process. This revolutionized the heat treating industry from the pack carburizing process of yesterday and easily enabled the future of boost/diffuse carburizing, carbon control and all the instrumentation and sensors that grew out of this invention.

Surface named this miracle endothermic gas with a tradename of RX® gas.

Today’s generator looks much different than that of it’s grandfather from the 1940s. A modular design allows for a specific flow range of consistent quality gas to be precisely developed. The quantity of RX endothermic gas required by you is accomplished by adding the necessary quantity of tubes (or retorts). The alloy retorts reside in high efficiency thermally insulated towers and are packed with nickel coated catalyst. These assemblies are heated to approximately 1950°F and have a mixture of air and natural gas passed though retort. The temperature and catalyst make mixture crack into the final RX endogas composition of 40% Nitrogen, 40% Hydrogen and 20% Carbon Monoxide.

Depending on the height of the alloy retort, maximum flow rates of 2000 cfh (cubic feet per hour) or 3000 cfh can be produced in each retort. It is important to note that as furnace equipment needs for RX gas change, which they will, our generators have 6 to 1 turn down capabilities meaning we can produce 1/6 of the nameplate maximum rating without sacrificing and quality of gas composition whatsoever.

To improve uptime of our gas RX generator many features are incorporated including on line burnout if an extra tube is selected where a retort can be taken offline and reconditioned by passing air through the retort while at temperature and a backup mixture pump which allows for switching on and off on the go to allow for continuous operation if a pump were to fail.

Control features include our ESA system which uses automotive oxygen probe technology to control the dewpoint (or carbon potential) of the resultant RX endo gas. This is used to control the RX endo gas composition. Our support team is always available for all of your endothermic gas generator troubleshooting needs. 

Today, we have a number of online diagnostic capabilities that tests for equalized flow in each retort and endo gas composition in each retort.

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