Study our website and you’ll see gaskets can be made from a wide range of materials. One of the most versatile yet under-appreciated of these is graphite. Graphite gasket temperature range handles temperatures from -400°F to +875°F, provide excellent dimensional stability and resist chemical attack. On top of that, they have an additional advantage that’s not obvious: they don’t stick to flanges.
The Cost of Flange Cleaning
When replacing a gasket it’s essential to clean flanges thoroughly. Many gasket materials stick to these flanges and have to be scraped off. That’s a problem, for two reasons. First, there’s a risk of scratching the faces while scraping, and that can create leak paths. Second, doing the job properly, (and avoiding early replacement,) takes time.
As explored in “Focus on the Cost of Sealing,” (December 2015,) gasket replacement almost always means taking equipment, or even an entire plant, offline. Each application is different, but the cost of downtime usually dwarfs the price of even the most expensive gasket. The less time that’s needed to swap out the old gasket for the new one, the faster the plant gets back into production, so anything that reduces down time is worth considering.
Graphite is one form of carbon. That’s the same element that forms diamonds. It’s strong, inert and resists temperature and pressure extremes, but what makes graphite special is its slipperiness. In graphite the carbon atoms are formed into layers that can slide over one another. That helps when closing up a gasketed joint because the material moves easily to fill uneven gaps and take up flange deformation or surface imperfections.
Graphite Gasket Materials
Here at Hennig Gasket we carry graphite material in a range of sheet thicknesses and widths as well as flexible homogenous graphite rolls. These can be cut to practically any desired shape and provide excellent sealing in many different applications. For especially challenging applications ask about the graphite-sided kammprofile gasket. Whichever graphite gasket you choose though, you can be sure of one thing; you won’t waste time scraping old material off the flanges!