Offers for fabric expansion joints „according to RAL“ are common. This is not a surprise as the RAL standard is respected worldwide. However, the offer can be an empty promise.
Compliance with the RAL regulations (RAL-GZ 719) is exclusively guaranteed by members of the RAL-Quality Association for Fabric Expansion Joints (Gütegemeinschaft Weichstoff-Kompensatoren e.V.).
Only these are entitled to carry the RAL Quality Mark after having passed the annually required monitoring tests by TÜV or VGB.
What counts in particular are the requirements for the components and the fi nished products with regard to:
Temperature resistance
Chemical resistance
Tightness
Tensile strength
Bending fatigue resistance
Pressure resistance
The above criteria are key for the quality of the fabric expansion joint.