When the donut-shaped o-ring was patented by Niels Christensen in 1939, he probably had no idea how this small-but-crucial part would evolve over the years.
Now, 60 years later, the o-ring is one of the most commonly used sealing solutions in a number of industries, including automotive, military, plumbing, jewelry and many other applications.
While the o-ring’s basic shape has not changed — it still lives up to its name as a small circular ring, there have been a number of improvements in o-ring technology over the years.
The Materials Used to Make O-Rings Are More Diverse Than Ever
As Hydraulics Pneumatics notes, because o-rings are used in so many different types of industries, they must survive a wide range of temperatures. In addition, o-rings must be able to resist a number of chemicals that they can encounter when they are placed into; for example, a car’s air conditioning or braking system. O-rings that are currently on the market are often made from a combination of ingredients, including polymers or elastomers, inert fillers like carbon black, accelerators — which will help with curing and anti-degradients that will help discourage unwanted chemical reactions during compounding.
O-Rings Can Thrive and Survive in Extremely High Temperatures
Expanding a bit more on the aforementioned point about o-rings and tough conditions, business owners who need o-rings to help seal high temperature systems can definitely find what they need. For example, Apple Rubber manufactures Viton fluorocarbon o-rings that offer impressive temperature and chemical resistance. These black o-rings are used for seals in aircraft engines, automotive fuel handling systems and other applications that includes exposure to a wide number of chemicals. To get technical for a minute, Hindawi notes that Viton is a fluoropolymer elastomer that is categorized under the ISO 1629 designation, and its density of 1800 kg/m3 is much higher than most other types of rubber. In regular English, what this means is that the standard Viton o-ring can withstand temperature extremes from -13 degrees to 446 degrees Fahrenheit, and they are highly resistant to swelling in high octane and oxygenated fuel blends.
Advancements in O-Ring Testing
Within the last several years, there have been a number of advancements in the way that o-rings and the elastomers that make them can be tested and analyzed. These more advanced tests can help accurately determine how harsh environments may negatively impact the elastomer. More specifically, tests have been created that imitate the way the o-rings are used in various industries; this includes a “stress-relaxation” test of o-rings that shows how they will stand up to chemicals and extreme temperatures in the real world. As you might suspect, the goal of these tests is to predict the potential failure of certain components in the lab, before they can actually happen. Using this data, engineers are continuing to find even better sealing options for a number of industries.
Niels Christensen Would Be Impressed
It is interesting that a small part with such a basic shape can still be modified and changed for the better. If Niels Christensen were still alive today, he would undoubtedly be impressed by the way his patented donut-shaped part is made up of a number of materials, can survive in a number of hostile environments and is still being tested for additional improvements.