Ключевые слова:
Sealing rings, Seals, Toroidal sealing rings, Elastomers, Natural rubber, Synthetic rubber, Pipe couplings, Pipes, Pipelines, Drainage, Sewers, Rainwater pipes, Drainpipes, Water supply and waste systems (buildings), Potable water, Polymers, Thermoplastic polymers, Moulded materials, Hardness, Grades (quality), Ageing (materials), Compression set, Tensile strength, Elongation at fracture, Stress relaxation, Ozone, Quality assurance