Effect Of Natural Gas Composition Variation On HVOF Process And Coatings

Natural gas represents the lowest cost, most widely available fuel gas for high velocity oxygen fueled (HVOF) thermal spray. Natural gas is also a mixture of hyrdocarbons and other gases that can fluctuate over time or from one location to another based on the source of the gas and the processing it has undergone before delivery to the end user. The present work seeks to determine the impact that changes in natural gas composition can have on the HVOF process in order to ensure that quality and consistency of the resulting coatings is not negatively impacted.

In order to accomplish this, data was collected in the United States, as well as from a natural gas utility supplier in Europe. Acceptable limits for utility suppliers were also examined and a Wobbe index was calculated for each data point. Based on these results, customized blends of natural gas were procured that represented low, middle, and high Wobbe index values. These custom blends were used to spray specimens in a laboratory environment while collecting process data and the coatings were ultimately characterized to determine if measurable differences existed.