After installing our self grip top seal profiles, it is important to ensure that the compression of the sponge part should not exceed a maximum of 50%. Exceeding this can greatly affect the overall compression and recovery of the product. An ideal compression rate should be between 30-40%, as this allows the product to return to its original state. If the sponge part of the profile has two sections then apply this value should to each section.
The crucial quality for sealing products is the enduring deformation. This essentially refers to how well the product recovers after you compress it at a specific temperature for a length of time. The most common characteristic is the compression set (DVR) ASTM D395. In order to determine this vale, the sponge part of the product is compressed by 25% and then stored at a set temperature for a predetermined period of time. After the product has been released and left at room temperature for 30 minutes, the height or width (depending on position) is measured and the enduring deformation can be identified. A DVR of 0 would indicate that the test body has reached its original height (unlikely in reality), a DVR of 100% shows that the test body has no recovery and would remain completely deformed.
This is important to note because as the sponge compresses it puts pressure on the seal. After an extended period of time the rubber can deform. If the DVR is too high the elasticity performance and sealing will decrease affecting the performance of the product.