tender for overhauling of 145kv sf6 cb of cgl make at 132kv ss shikohabad under etd firozabad - to attend sf-6 gas leakage of 145kv sf-6 cb (cgl make s. no. 4859c, type-120-sfm-32b)a. direct pole leakage by sf-6 gas leakage detector. b. extract sf-6 gas from pole units by help of sf-6 gas extraction plant and keep it into empty sf-6 gas cylinder. c. dismantle all top covers from pole units and opening of fixed contact chamber from pole unit. d. cleaning of all fixed & moving contacts, polishing the contacts and applying micro carbon grease on contact surface.e. replace pole top cover o ring p-170, absorbant and re-fitting the same.f. apply vaccum in all poles by held of vacuum pump upto specified value and keep it for 4/5 hour & check no loss of vacuum. g. complete overhauling of spring charging mechanism assembly, cleaning & lubrication. h. dismantaling of close & trip coil assembly, opening its parts, cleaning, lubrication and adjuctment of air gap of this plunge. i. checking electrical connection in the marshalling box and tightening all electrical connection.j. check close / trip operation of this breaker satisfactorly.k. check close / trip timing by digital timer 2 replacement of main nrb with pipeline (if required) work consist of dismantling of main nrb with pipeline & replace it with new one & fitting at its original place in cb sf-6 gas filling in all poles at desired level for satisfactorly completion of work.