Noise Reduction Rings
The muting inlay of the manhole frame prevent the clattering of the cover and protects the surface contact area.
The excellent material properties (elastic modulus 220 Mpa. Shore Härte:55) of the Noise Reduction Rings contribute the protection of the sub-construcktion and the frame. In this way the Noise Reduction ring gets the necessary wear resistence for a long lifespan and is stable to frost, de-icing salt and other aggressive influence.
The material amongst other things is used as elastic interim storage beneath the rails of the Deutsche Bahn.
Despite of its elastic behavior the ring has a higher stiffness compared to other rings out of rubber or elstomer. That makes it easy to insert the ring to the manhole frame. The Noise Reduction Ring can’t be shifted or fall into the manhole while the cover is lifted.
The Noise Reduction Ring is able to eleminate unevenness in the frame of the cap permanently.
