User:Sudheersvsm

The sheath of the Telephone cables buried under ground sometimes gets damaged, e.g, during digging by another agency. When water enters the cable core radially at the point where the sheath is damaged, & if the conductors are paper insulated, water seeps through paper & creats a short cicuit. Even, if the conductors are plastic insulated, the entered water may flow longitudinally inside the cable core & may come in contact with the conductor through a pin hole in insulation & shall crate a short circuit. After trying many methods to avoid the longitudinal flow of water, a method is derived to fill the entire air space inside the cable with a soft, inert, water repellent material; hence leaving no space for the water to flow even if the cable is damaged at one point. Petroleum jelly, gelled Mineral Oil, or modified Polybutene is used as the filling compound. Each twisted pair units are twisted again to form Cable core. The core is then filled with Jelly & sealed with a core wrap of plastic tape. Over this, Aluminium Mylar tape is again wrapped which gets bounded with the Polyethene sheath. --Sudheersvsm (talk) 13:23, 4 June 2012 (UTC)