[en] It has been proposed that the Gentilly-1 (G-1) Generating Station be modified to supply process steam to the La Prade Heavy Water Plant (LHWP), but that the generating capability of the station be retained, varying from house load (approxmately 17 MWe) to the design value (250 MWe), depending on the steam requirement of the heavy-water plant. To achieve this versatility, four reboilers would be connected to the existing steam-mains system, and a new pressure controller would be required. We describe herein an inertial analysis of the hydrodynamic behaviour of both the existing and proposed G-1 steam-mains networks. In general, the hydrodynamic behaviour of the proposed steam-mains network would be about the same as that of the existing network, during disturbances of low frequency (< 1 Hz), at nominal operating conditions

[en] In order to increase the safety of a PWR plant, it is suggested to install a further safety valve in the steam line coming from the steam generator. The pressure threshold of this second safety valve is lower than that of the first. In case of accident, the second safety valve can be shut off. (HP)

[en] The live steam pipework system of the twin loop PWR has two pairs of live steam pipes with tee-offs, safety valves and outer shut-off valves. The steam raising units are situated inside the containment. Transverse connections are provided so that for unintentional closing of the shut-off valves the steam of a steam raising unit can be passed to the turbine via the second live steam pipe and is not blown off to the atmosphere. (DG)

[en] The valve for PWRs and BWRs, with diameters up to 1.25 m, for temperatures from -180⁰C to about 600⁰C and pressures up to over 50 bar, is designed for high reliability and long useful life. Two circular valve discs are moved as isolating elements in their plane across the steam direction and brought before the valve seat within a valve chamber. Shortly before reaching this final position, each disc is rotated by a small amount about its axis. Only after reaching the final position a double-wedge, further pushed forward between both discs, produces the necessary contact pressure. By revolving and frictionless closing caking together at high stresses and temperature variation is prevented and permanent tightness assured. The valve body is moved in a cylinder, cast on the valve housing, by means of a stepped piston. Its larger diameter is guided in a second cylinder flanged on above. In the cover of the second cylinder a pilot valve is mounted being controlled over 2 parallel solenoid valves by means of compressed air. In normal operation process steam from the valve chamber serves to move the stepped piston with the valve chamber. On closing of a bore, connecting both cylinder spaces, by the pilot valve the main valve is opened. If the pilot valve is opened the steam through the connecting bore is acting on both piston stages and closing the main valve. On loss of steam (pipe break) or for testing purposes one or the other cylinder space over solenoid valves is acted upon by auxiliary energy or evacuated, the main valve thus being controlled. (HP)

[en] A blocking device for use in secondary pipelines. The device ensures that, in any kind of operation and at any possible case of disturbance, at least one of the two pipelines transporting a medium which is under pressure is open. To solve this task, the two openings of the slide are formed as long holes twice as long as the slide's shutting move corresponding with the pipeline diameters which are to be blocked. (orig.)

[en] This report presents RELAP5/MOD2 calculations of the 100% steam line break test T-2013 performed on the Westinghouse Model Boiler-2 facility (MB-2). The input deck uses a noding structure typical of what would be used for an integral rig or full plant study using the RELAP5/MOD2 code. Sensitivity calculations were performed for the break junction discharge coefficient and the separator drain line loss coefficient. (author)

No abstract available

[en] For the Korean Next Generation Reactor(KNGR) development, LBB is considered for the Main Steam Line(MSL) piping inside its containment to achieve cost and safety improvement. To apply LBB concept to MSL, leak sensors highly sensitive to humidity is required. In this paper, a ceramic material, MgCr₂O₄-TiO₂ has been developed as a humidity sensor for MSL applications. Experiments performed to characterize the electrical conductivity shows that the conductivity of MgCr₂O₄-TiO₂ responds sensitively to both temperature and humidity changes. At a constant temperature below 100 .deg. C, the conductivity increases as the relative humidity increases, which makes the sensor favorable for application to the outside of MSL insulation layer. But as temperature increases beyond 100 .deg. C, the sensor composition should be adjusted for the application to KNGR is to be made at temperature above 100 .deg. C

[en] This study is to present the relaxation of the pressure and temperature(P/T) for Subcompartment during Main Steam Line Break (MSLB). The doubleended MSLB in the steam bunker corresponds to the limiting accident in the point of maximum P/T. The analysis results for the steam bunker with LOFTRANCOMPARE for M/E and P/T, respectfully, show that the maximum pressure difference is 1.45bar and the maximum temperature is 250 .deg. C. The temperature is too high to qualify the equipment for these environmental Temperature (generic limit 182 .deg. C) conditions. It is recommended to optimize the temperature result. To do so RELAP-TRAPSCO are used to analyze mass/energy (M/E) release and P/T. Finally, the result of RELAPTRAPSCO shows that the peak temperature is lower than that of LOFTRAN-COMPARE

[en] In accordance with the present invention, a power plant includes a steam source to generate superheat and reheat steam which flows through a turbine-generator and an associated bypass system. A high-pressure and an intermediate-pressure turbine portion drive a first electrical generating means, and a low-pressure turbine portion drives a second electrical generating means. A first flow of superheat steam flows through the high-pressure portion, while a second flow of reheat steam flows through the intermediate and low-pressure portions in succession. Provision is made for bypassing steam around the turbine portions; in particular, one bypass means permits a flow of superheat steam from the steam source to the exhaust of the high-pressure portion, and another bypass means allows reheated steam to pass from the source to the exhaust of the low-pressure portion. The first and second steam flows are governed independently. While one of such flows is varied for purposes of controlling the rotational speed of the first generating means according to a desired speed, the other flow is varied to regulate a power plant variable at its desired level. (author)