O-Rings are a small yet critical component in the proper function of equipment in the pool and spa industry. As in any application, the size and compound of each application are important. The O-Ring Store stocks or can fabricate any O-Ring needed to either manufacture equipment or keep your equipment running optimally.
O-Ring Sizing in the Pool and Spa Industry
Many O-Rings for equipment such as pool pumps or filters have both standard and non-standard sizing. PVC unions will have standard sizes that are readily available molded sizes, while there will be larger and custom spliced and vulcanized O-Rings that will need to be fabricated. The O-Ring Store can provide both options in small quantities or larger quantities for equipment manufacturers. The two critical pieces of information needed to ensure proper sizing are the Cross-Section Width and your Inside Diameter. With the advent of Olypsys Technologies, the app that lets you measure O-Rings with your phone, it removes the guesswork in cases where you do not have the information, or company acquisitions have lost or changed the dimensions of legacy parts. You can simply measure the O-Rings with your phone, and The O-Ring Store can provide them easily. If you do not have this information, we provide many parts that have been measured and cross-referenced in our OSK Pool, Spa & Pump O-Rings section of our website. This makes getting the right size easy from the manufacturer looking for precision and bulk orders, down to the end user looking to maintain equipment for their customers.
O-Ring Compounds Used in the Pool and Spa Industry
There are typically only three compounds used in this industry: Buna-N, Viton/FKM, and EPDM. Here is a description of these materials and their specific uses, benefits, and shortcomings that you will come across.
This compound is the least expensive and the most readily available O-Ring compound across all industries. For the pool and spa industry, it is commonly used but does not hold up as long in chlorinated water applications. If you have ever taken an O-Ring out of your equipment that is hard, brittle, and leaves behind a black powder on your hands and in its installation location, this is likely what has been installed. Buna-N in a chlorinated application will need to be replaced within a year or less. For a saltwater application, Buna-N will have a longer operational life. It is also not recommended for applications involving direct UV light exposure.
The most expensive commonly used compound in the pool and spa industry, but provides the best resistance to chlorinated water. This will give you the most reliable and maintenance-free service life. It is best to stick with this compound for locations that are difficult to get to and replace the O-Ring after installation.
The middle-of-the-road compound for cost and chlorine resistance. EPDM is a very common material that will be less expensive than Viton/FKM, especially in larger sizes. It is not as resistant to chlorine as Viton/FKM but much better than Buna-N. For larger vulcanized sizes that may be cost-prohibitive, this is a great option that will give you a service life that will not have you returning to your equipment in short service spans. EPDM is also great for UV exposure resistance, so it is often used to seal lights or other translucent fixtures in or around pools. The downside is that you may not use petroleum-based lubricants or be used in saltwater applications.
All three of these compounds are readily available in standard AS568 Sizes, Metric Sizes, and Custom Vulcanized Sizes.