The Metro rail project of Mumbai Metropolitan Region Development Authority (MMRDA) plans to use elastomeric pads to control the noise levels of running trains.
Mumbai is a city with a population density of about 30,000 people per square kilometer. “The total length of Metro rail will be more than 145 km. There are many schools, colleges and hospitals in vicinity of the project and in future more such institutions might come up alongside the project. We had to emphasise on the technology which would provide excellent services to the commuters along with least possible disturbances to the people of Mumbai,” says Joint Project Director (PR), Dilip Kawathkar.
The elastomeric pads will be installed between concrete structures and tracks. This will help in reducing vibrations and noise. This technology is used globally in many industries including railway tracks, railway bridges, constructions, etc., noted Kawathkar.
But aren’t elastomeric pads patented? (for instance, United States Patent 5551633). “In a railroad track comprising a railroad rail having a lower flange and a railroad tie made from concrete, a polyurethane pad is mounted between the lower flange of the rail road rail and an upper surface of the railroad tie. A bonding layer at least as flexible as the polyurethane pad is bonded to a lower surface of the polyurethane pad. An adhesive layer is bonded to the upper surface of the railroad tie. The bonding and adhesive layers are bonded to each other, whereby the polyurethane pad and the railroad tie are bonded to each other via the bonding and adhesive layers…” The inventors are Kish, Frederick A (Wheeling, IL); Rancich, Michael J. (Mundelein, IL).
If patented, MMRDA will have to pay royalty for the elastomeric pads.
I guess MMRDA would have figured this out by now. Else the pads may reduce noise but a lot more noise will be created by the patent holders.
