[en] High pressure feed water heater on unit 1 at Tarapur Atomic Power Station (TAPS) showed tube leaks in early 1972 after about two years of satisfactory operation. Subsequently the tube failures showed to be alarmingly high and confined to particular regions in the drain cooler zone. Problem of internal damage was suspected when recurring tube leak showed up. An attempt was made to withdraw the tube bundle, investigate for any generic problems and repair as possible. This exercise was carried out in the year 1977. The present paper describes the investigations earlier carried out and the rehabilitation attempts including changes in operating procedures made to extend the life of the heater tube bundle until re-tubing of the affected drain cooler region could be made. (author)

[en] Water chemistry is an important parameter for deciding radiation levels in operating areas of a nuclear power plant. Clean-up deminilisers at TAPS 1 and 2, containing mixed bed resins are used to remove soluble and insoluble impurities from reactor water. The clean-up deminilisers bed is in continuous service for one complete cycle of reactor operation. At the end of cycle when the bed is depleted, the resins are highly radioactive. Till now, depleted resins are transferred to Spent Resin Storage Tank (SPERT) for interim storage

[en] The need for and essential characteristics of both internal and external communication systems for a nuclear power plant are explained. Various communication systems deployed at the Tarapur Atomic Power Station are described. (M.G.B.)

[en] Published in summary form only

[en] Various steps adopted in design of the instrumentation system of the Tarapur Atomic Power Station are discussed with the help of a flowchart and various types of reference documents generated in this process are enumerated. Illustrations of a typical section of an instrument, an electric schematic and installation detail are given in the form of diagrams. (M.G.B.)

[en] The paper describes salient points of Tarapur Atomic Power Station experience of 22 reactor-turbine years of operation. Details of major inspections, planning and the experience gained are given in respect of turbine components - rotors, bearings, diaphragms, casings. Nuclear steam from boiling water reactor did not significantly affect maintenance works of turbine. Dry saturated steam, and low speed turbines associated with boiling water reactors need higher volumes of flow of steam and erosion due to moisture in steam path is of major consideration. (author)

[en] This work was taken up for the first time in the history of TAPS 1 and 2. ALARA meeting was conducted before taking up the work to estimate the collective dose requirement based on the radiological status during unit outage. Though the entire work was to be carried out in low background of 10-150 μGy/h, owing to very large manpower requirement, it was considered to be a collective dose intensive job. Mock-up facilities were established for training of contractor personnel which were helpful for accurate estimation and reduction of man-hours in field conditions. Tube removal was planned to be carried out using pneumatically operated tool from the inlet side where the anticipated radiation level was 10-20 μGy/h. As per the plant lay out, the condenser tube removal pit is located outside the turbine building in the uncontrolled area. A shed was erected covering the condenser tube removing pit and near by area in order to facilitate the tube removal and to prevent spread of contamination

[en] Radionuclide are generated in the reactor by the processes of fission and neutron activation of corrosion and radiolytic products. TAPS 1 and 2 being a BWR type reactor, with primary steam reaching right up to the turbine, radionuclide generated in the reactor are carried along with steam to different parts of the plant covering larger portion of the operating area. This paper aims to share the operating experiences gained during the removal of hotspots at CRD housing area and Reactor Basin Cavity area of TAPS-1, using PVC-SCUI solution (PVC Solvent Cement solution) based on peeling techniques

[en] Tarapur Atomic Power Station 1 and 2 (TAPS 1 and 2) is a twin Boiling Water Reactor (BWR) nuclear power station, with each unit operating at 160 MWe. Both the units were commissioned in November, 1969 and completed about 40 years of commercial operation. At TAPS-1 and 2, electrical cable penetration fire barriers of required fire ratings are installed in different fire compartments to ensure integrity of the compartments. However, while implementing various modifications, these fire barriers need to be broken for cable routing or re-routing etc. If there is some lapse in normalisation of fire barriers after breaking, it may remain in open condition, until it is noticed during the next periodic inspection. Till that time, the broken fire barrier at electrical cable penetration may remain in breached condition. In order to alleviate this concern, a software based fire barrier permit system was developed and integrated with the existing Computerised Maintenance Management System (CMMS). This permit system is designed for tracking works on fire barriers, right from the permit initiation for fire barrier breaking to surrendering of permit after normalisation of fire barriers. This paper looks into salient features of 'Fire Barrier Permit System' introduced at TAPS-1 and 2 from fire safety point of view involving electrical cable or cable penetration. This paper briefly touches upon the salient features of fire barriers, fire rating of the compartments, standard time-temperature curve and qualification test of fire barriers also. (author)

[en] This paper describes improved practices followed at TAPS - 1 and 2, major modifications carried out at TAPS - 1 and 2 for minimizing discharges from station and in maintaining lower discharge water temperature from station to sea, station statistics of waste discharges for last few years, environmental monitoring scheme followed at nearby TAPS- 1 and 2 station locality and results thereon. (author)