Vehicles need rubber door and window seals that can withstand low temperatures.

Paulo Arruda
Purchasing and Logistics at Elasto Proxy

Cold temperatures can cause rubber parts to contract, lose their flexibility, and become brittle. These problems affect seals and gaskets, which can harden at low temperatures and resist deformation to pressure. Here in Canada, where Elasto Proxy is based, suppliers of on-road and off-road vehicles need door and window seals that won’t quit when the weather grows cold. Manufacturers in other parts of North America and all around the world also need sealing and insulation for extreme environments.

For over 25 years, Elasto Proxy has specialized in the design and custom fabrication of rubber products for a variety of industries. By analyzing your requirements and listening to your needs, we can help you select the right rubber for your low-temperature application. Material selection can be complex, and all rubber isn’t the same. If you choose a compound that contracts at cold temperatures, seal failure may occur. When the contact surface shrinks, look for leaks of liquid or air.

Fortunately, technical buyers don’t have to be material scientists to avoid seal-related problems. By understanding what to ask for – and that many different types of rubber are available – you can select a compound that’s made with just the right recipe for your application. Vulcanization, a chemical process that uses sulfur or other curatives, converts polymers into more durable materials. Vulcanized elastomers are made of natural or synthetic rubber, and meet specific low-temperature requirements.

ASTM D2000 Callouts for Low-Temperature Rubber

ASTM D2000 is a published standard that provides buyers and suppliers with a common way to describe vulcanized rubber materials. Originally designed for automotive applications, this publication from ASTM International is used also by other industries.  As How to Read ASTM D2000 Specifications explains, the ASTM D2000 description for a vulcanized rubber contains letters and numbers that designate or “call out” specific material properties and testing conditions.

In the ASTM D2000 specification, the letter F is used as a callout to indicate low temperature resistance. This letter is then followed by a number that indicates the test method and test temperature. For example, the callout F17 indicates that the material was tested under ASTM D2137 for its ability to withstand breaking when bent at a given temperature for a period of time. This three-minute test is performed at temperatures under -40° C, and the sample must be non-brittle at the end of the test.

Vulcanized rubber with the callout F19 is also tested under ASTM D2137 for brittleness point, but under even colder conditions. This three-minute test is performed at temperatures under -55° C, and the test sample must be non-brittle at the end of the test period. If your project specifications state temperature requirements in Fahrenheit, note that -55° C equals -67° F. Because of the way that degrees Celsius are converted to degrees Fahrenheit, however, -40 C° equals – 40° F. You can learn why here.

Additional Application Considerations

Many rubber products that are exposed to low temperatures are used in outdoor conditions. That’s why suppliers of mobile specialty vehicles need to select compounds that can withstand sunlight, water, and even road salt. EPDM rubber is often the right choice for these outdoor environments, with applications ranging from door seals to hoses and tubing. Indoors, EPDM seals are used with cold-room doors since this synthetic rubber is an effective insulator.

Does your project require an elastomer than can resist low temperatures along with oils and lubricants? Do you need to source cost-effective compounds that can withstand both low and high temperatures? By taking the time to understand everything that you need, Elasto Proxy can recommend the right rubber, strengthen your seal designs, and then custom fabricate high-quality rubber parts for you.

How can we help you choose the right rubber for low temperatures? Contact Elasto Proxy on-line to learn more about what we can do for you. You can also join the conversation about this topic on LinkedIn, Facebook, Google+, and Twitter. Elasto Proxy has a YouTube channel, too. There, you’ll find our Capabilities video, as well as other informative content. Finally, please subscribe to our free e-newsletters. They’re a great source of information, too.