The Latest Advancements in O-Rings
The o-ring is one of the most widely used sealing solutions in the world. While the basic shape has not changed since Swedish inventor J.O. Lundberg applied for a patent for the circular seal in 1896, o-rings have changed over the years in many other significant and interesting ways.
Read on to learn more about the latest advancements in the technology of o-rings, including the materials from which they are made and how they are tested.
The Evolution of Materials
At their most basic, o-rings are made from polymers or elastomers, as well as some fillers and other materials that will help ensure that they will not harden. As Hydraulics & Pneumatics notes, the materials made to create the seals are now specialized for how each o-ring will be used. More than 20 engineering polymers are now available for creators of o-rings, and a great deal of research has taken place over the years to be sure that each type of o-ring holds up in its specific use. For example, chemists have found that by changing the amount of fluorine in fluorocarbon-based polymer o-rings, their ability to withstand chemical and temperature changes can be improved.
Addition of Numerous Sizes and Custom O-Rings
Rather than rely on a small number of sizes of o-rings, industries ranging from automotive and medical to aeronautical and more can now choose from a huge variety of sizes. And, if for some reason a certain size of o-ring is not available, business owners are able to custom order the o-rings they need from a manufacturer like Apple Rubber. The company currently has 8,000 non-standard o-ring sizes in stock; these include AS568 and ISO 3601 standard sizes in a hardness range of 10 to 90 Shore A durometer. The team will also be happy to make custom o-rings, using their in-house tooling and manufacturing equipment.
O-Rings Are Now Tested in a Myriad of Ways
O-rings typically have incredibly important jobs to do, from making sure syringes deliver the proper amount of medication to ensuring that fluids do not leak out inside of cars or planes. To assist with this, o-rings now go through a variety of tests to check for things like surface defects, ozone resistance, tensile strength and more. These tests, which have expanded and evolved over the years, also check for the hardness of the o-rings, how heat and chemicals affect them, that the measurements are absolutely correct and that they are up to the ASTM and ISO standards.
Updated Molding Techniques
O-rings have traditionally been created with molding and press techniques, but for larger o-rings, some manufacturers have used a splicing technology. While this approach works for large o-rings that are not under a lot of stress, there has been concern that the connected area, which is the weakest part of a spliced o-ring, could potentially come apart. Over time, inventors have created a molding technology that will create strong and large o-rings in one piece, thus eliminating the need to splice the seal.
What Will the Future Hold?
While the o-ring may seem somewhat basic at first, a lot goes into the creation of these small yet mighty seals. If J.O. Lundberg were around today, he would undoubtedly be impressed with the advancements in materials, sizes, testing and molding that have allowed the o-ring to be safely used in so many industries.