The material specialists in the Roxtec material laboratory in Karlskrona, Sweden, use advanced equipment to simulate aging. By making materials, products and complete sealing systems age, they test long-term protection features and develop enhanced solutions. This can result in rubber made from sugar canes with sealing properties matching silicone.
If you want to speed up aging to be able to check effects over time, you have to simulate the impact of pressure, heat, vibration, chemicals and the overall environment. Let us follow the proven procedure of Roxtec material specialists Pontus Danielsson and Panch Svensson.
Blending the rubber compounds
In order to create or improve a sealing solution, you may need to develop a new rubber compound. This means weighing ingredients, mixing in selected fillers and rolling the material. That is, however, not enough to create a perfect rubber. The new material must also be suited for large-scale production.
All these steps, from blending to rolling, are possible in the miniature rubber factory. There is also equipment for testing, pressing and measuring performance of products and systems.
Roxtec material specialist Panch Svensson improves materials by fine-tuning mechanical, physical and chemical properties.
Simulating the aging process
The properties of a material or a sealing system can change a lot due to heat and compression. The higher the temperature, the faster the aging. Compressing the rubber is another well-known way of speeding up the aging process. When it is subject to temperature increase and heavy pressure, the rubber loses its internal structure. Ensuring reliable and durable resistance to heat and pressure is therefore a way of fighting aging.
“We use temperature cabinets to temp-cycle entire systems. We have also developed equipment for warming up the contents of process pipes to see how the system will react during operation. We verify both existing seals and new materials,” says Pontus Danielsson.
Roxtec products withstand fire and water ingress for at least 25 years. In the stress relaxation test, the material is tested for long-term exposure to pressure, high temperature and chemicals.
Ready for decades outdoors
The material specialists study the swelling and shrinking of materials due to temperature changes. A cable and pipe seal installed in a sunny southern wall in a cold climate, for instance, must cope with ice, heat and meltwater. Variations between -65°C and +80°C can affect the rubber’s “memory”, or the spring back to its original shape after compression.
“This knowledge has helped us develop a rubber that is very good, unlike what many others have. By fine-tuning our EPDM rubber recipe, we have managed to create a new rubber compound. We can now copy the sealing features of expensive silicone,” says Pontus Danielsson.
The new rubber from Roxtec is a high-end product that will be an alternative to silicone.
The climate chambers in the Roxtec material lab are used to simulate aging. Materials, products and entire sealing systems are exposed to temperatures from -70°C to +180°C.
Combining risk factors
Roxtec sealing solutions are famous for providing protection against multiple risks. Already in the material development process, heat and pressure team up with high-cycle exhaustion and nasty chemicals. Vibration can affect the rubber surface, so endurance is crucial for long-term tightness. Often, the material is required to resist hot and aggressive chemicals.
“We are market leaders because we look beyond certificates and industry standards,” says Pontus Danielsson. “We are, for example, now predicting demands that will be standard requirements in 5 to 10 years.”
Material specialist Pontus Danielsson and his colleagues at Roxtec are striving to protect life and assets against multiple risks and have developed rubber for efficient underground sealing as well as firestops including halogen-free flame retardant.
Quality for sustainability
There are two important green aspects of the work in the Roxtec material lab. Today, EPDM rubber is made mainly from fossil crude oil, but Roxtec has found ways to produce 70% of it from fossil free raw material in the form of sugar canes – all while maintaining the sealing performance.
Another environmentally friendly factor is the durability of the safety seals. A lifecycle of 25 years is an expression of sustainability.