Abstract: A pipe for supplying pressure medium to valve train elements, including: an outer wall; a partition located inward of the outer wall and twisted in a spiral along the outer wall; a first gallery formed by the partition and the outer wall; a second gallery formed by the partition and the outer wall and separate from the first gallery; and a plurality of overflow openings. Each overflow opening opens to the first gallery or to the second gallery.

Abstract: A gas stripper system for purification of a primary coolant contaminated in cooling a nuclear reactor is provided. The gas stripper system includes a gas stripper column and a condenser arrangement. The column is adapted to receive the liquid phased contaminated primary coolant. The column defines top, bottom and middle sections and includes a distributor member, a re-boiler member and a separation member disposed therealong. The distributor member, a re-boiler member and a separation member with structured packing are configured such that maximum contact between the liquid phased primary coolant and gaseous phased primary coolant is made. Moreover, the condenser arrangement is configured to the gas stripper column to receive and condense the vapour phased primary coolant.

Abstract: The dual chamber system has a source chamber and a receiver chamber. The source chamber generates a first steam in a first steam section, and the receiver chamber generates a second steam in a second steam section. The first steam is at a higher temperature than the second steam, and the first steam is at 100% quality. The first steam is injected into a mixing section of the receiver chamber to generate a condensed steam. A sensor or instrument can then be calibrated by the condensed steam. The measurement being taken with the sensor or instrument will have reliability and accuracy. The method includes generating the first steam, generating the second steam, injecting and mixing the first and second steam to form condensed steam at a metering point in the receiver chamber, and calibrating a sensor or instrument at the metering point.

Abstract: A two-stage dust-air separation structure includes a cyclone separator and a spiral dust-air separation device. A first stage separation of dust from air is realized by a cyclone housing, and by arranging a second-stage cyclone barrel 5 inside the cyclone housing and arranging the spiral dust-air separation device at a barrel opening of the second-stage cyclone barrel, the dusty air, after going through the first stage separation, is guided by the spiral dust-air separation device to form, on an inner wall of the second-stage cyclone barrel, an airflow rotating towards the barrel bottom, and the dust in the airflow is driven by a centrifugal force to rotate downwardly to the barrel bottom and be collected in a second-stage dust collecting space, and the air in the rotating airflow is extracted by the negative pressure, thereby realizing a second stage separation of dust from air.

Abstract: A heat exchanger pipe in a flow duct for gases. The pipe first section has a second section with an inner pipe for transferring heat transfer medium; an outer pipe that radially encloses a part of the inner pipe; and a medium layer between the outer pipe and the part of the inner pipe. The second section of the heat exchanger pipe bends less than 90 degrees. Furthermore, the first section is insulated in its entirety, or non-insulated in the vicinity of other heat recovery surfaces only. In the device the temperature of the heat transfer medium flowing in the inner pipe is at least 500° C., the temperature of the outer surface of the outer pipe is higher than 600° C., or an auxiliary agent is fed to the thermal device.

Abstract: A method for cleaning and conditioning the water-steam circuit of a power plant, especially of a nuclear power plant, uses an amine as a film-forming agent. The amine is metered into the working medium circulating in the water-steam circuit. The film-forming agent forms a hydrophobic film on the surfaces of the circuit. During the process, the concentration of at least one impurity contained in the water and the concentration of the film-forming agent in at least in the feed water of the steam generator are measured and monitored. The concentration of the film-forming agent is varied, as needed, subject to the concentration of the impurity.

Abstract: A wipe warmer having a container to receive liquid and sponge pad therein, where the container is placed under the wipes to keep the wipes moist. The container has a top and a support plate within, both of which are perforated allowing moisture to pass through. These perforations offset each other to facilitate efficient saturation of the sponge pad, when the sponge pad is placed between the perforated top and the perforated plate. Further, the container can be a removable basket-like structure. Alternatively, all or part of the container can be an integral part of the wipe warmer. While the wipes can be placed on top of the container, an alternative design is to place the wipes and the container side-by-side.

Abstract: Disclosed herein is a method of controlling the operation of an oxy-fired boiler; the method comprising combusting a fuel in a boiler; producing a heat absorption pattern in the boiler; discharging flue gases from the boiler; recycling a portion of the flue gases to the boiler; combining a first oxidant stream with the recycled flue gases to form a combined stream; splitting the combined stream into several fractions; and introducing each fraction of the combined stream to the boiler at different points of entry to the boiler.

Abstract: A gas-sensor control device includes a sweep circuit, a return sweep circuit, and a control portion. The sweep circuit energizes a detection current to flow through an oxygen sensor to calculates an impedance of the oxygen sensor. The return sweep circuit energizes a neutralization current to flow through the oxygen sensor in a direction opposite to a direction of the detection current, so as to remove electricity from the oxygen sensor that is energized by the detection current. The control portion executes a detection of an off failure of the sweep circuit and the return sweep circuit, only based on a sensor voltage acquired in a time period where the neutralization current flows through the oxygen sensor, and a threshold.

Abstract: A steam assisted ring style desuperheater includes a ring body defining an axial flow path and one or more spray nozzles extending through a wall of the ring body. Each of the nozzles is connected to a separate cooling water manifold and atomizing steam manifold to conduct cooling water and atomizing steam separate from each other through the spray nozzle to an injection point. An atomizing head of each nozzle combines the cooling water and atomizing steam to form a spraywater cloud that is injected radially into the axial flow path. The spray nozzles include one or more flow passage inserts that define separate first and second fluid flow paths for conducting the cooling water and the atomizing steam separately through the spray nozzle.

Abstract: A steam conditioning system for discharging bypass steam into a condenser of a steam powered generating plant and other uses. The system includes a steam conditioning device comprising an inner evaporative core and an outer shell. The core may be formed of a tubular piping section disposed at least partially inside the outer shell forming an annular space therebetween. An inlet end of the core receives steam from a piping header fluidly connected to an upstream desuperheating pressure reducing station which injects liquid coolant into the steam stream. Steam discharges through the core outlet end into the outer shell, reverses direction, and flows into the condenser. In one embodiment, the steam conditioning device may be disposed inside the dome of the condenser except for the inlet end. The device intends to increase flow residence time to evaporate entrained carryover coolant droplets in the incoming steam before release to the condenser.

Abstract: The invention refers to a forced flow steam generator (10) and to a method for its operation. The forced flow steam generator (10) has a combustion chamber (11) with a burner arrangement (20). A fuel (B) and a mixture (G) consisting of pure oxygen and flue gas (R) are fed into the combustion chamber (11) or to the burner arrangement (20) for combusting. A flue gas duct (27) is connected to the combustion chamber (11) in the flow direction (S) of the flue gas (R), and a flue gas passage (26) is connected to the flue gas duct. The flue gas (R) for the oxygen-flue gas mixture (G) is fed back from the flue gas passage (26) via a flue gas recirculation line (28). The forced flow steam generator (10) is operated in the so-called oxyfuel process. A plurality of auxiliary heating surfaces (35) are arranged in the flue gas duct (27) downstream of the burner arrangement (20).

Abstract: A circulating fluidized bed boiler includes a rectangular furnace having multiple particle separators connected to an upper portion of each of a front wall and a back wall of the furnace. Each particle separator includes a gas outlet, and a flue gas duct system connected to the gas outlets for conducting cleaned flue gas to a back pass. The particle separators are arranged in pairs. Each pair includes a front separator arranged adjacent to the front wall and a back separator arranged adjacent to the back wall. The flue gas duct system includes cross over ducts, each duct connecting the gas outlet of a front separator of a pair of particle separators, across and over the furnace, to the gas outlet of the back separator of the same pair of particle separators, and to the back pass, which back pass is arranged on the back wall side of the furnace.

Abstract: A steam boiler includes a boiler housing. A helical coil for boiling water and superheating the wet steam is disposed within the boiler housing. A burner emits combustion gases which heat a heat emitter which is disposed in the inner space of the helical coil. Combustion gases from the burner enter the internal cavity of the heat emitter and then pass through perforations in the heat emitter before contacting the helical coil. As such, the heat emitter is heated by the combustion gases and serves as a radiant heat source for the helical coil.

Abstract: A steam generator having a heat transfer tube group formed of a plurality of U-shaped heat transfer tubes; an annular channel formed to cover the circumference of the heat transfer tube group; the annular channel having an opening that communicates with the heat transfer tube group; a water supply unit disposed at an upper portion of the annular channel and supplies water to a descending-side portion; a steam/water separator disposed above the heat transfer tube group; and an air bubble removing member for removing air bubbles provided in the annular channel.

Abstract: A method for regulating a steam bypass valve is provided. The bypass valve is arranged in a steam line and the steam line includes a device for spraying water. The equation, t Rest , 0 = FB max m . W , SOLL - m . W , IST is used to determine when to close the steam bypass valve. The steam bypass value is closed when tRest,0 is smaller than a value ?t. An actual volume of water {dot over (m)}W,IST, a desired volume of water {dot over (m)}W,SOLL and a maximum water-volume deficiency FBmax are used in the equation.

Abstract: A method for producing steam includes combusting a fuel and an oxidant to generate heat in a combustion stream, and injecting impure water into the combustion stream such that the heat produces a steam stream including particulate matter precipitated from the impure water.

Abstract: A method for determining carbon emissions from a steam generation system is disclosed. It includes measuring a first energy of feedwater entering into a steam generation system and measuring a second energy of steam exiting the steam generation system. The first energy is subtracted from the second energy to determine a total energy absorbed by the steam generation system. The total energy absorbed by the steam generation system is divided by the total energy to determine a heat input to the steam generation system. The heat input is used to determine the carbon emissions from the steam generation system.

Abstract: Electrical household appliance comprising a base (1) for the generation of steam, having a liquid tank (6) mounted removably on a receiving socket (10) and having a steam generator located outside of said tank (6), the steam generator being supplied by gravity by a supply line from the tank (6) and having a steam outlet through which the steam can escape towards a work tool, such as a crease-removing brush, said supply line comprising an inlet orifice located on the receiving socket (10), and said tank (6) comprising a closed enclosure (61) having only one outlet orifice (52) which connects the said inlet orifice when the tank is placed on the receiving socket (10), which appliance is characterized in that said tank (6) connects leaktightly onto said receiving socket (10) and in that said appliance has a vent line admitting air to the outlet orifice (52) of the tank, said vent line having one end connected to the exterior which is higher than the outlet orifice (52) of the tank.

Abstract: A steam generator, used in a helical coil type steam generator for a sodium-cooled fast reactor which has heat transfer tubes of a double-wall tube structure, with high heat transfer efficiency and a heat transfer tube damage detection unit that can detect on-line in real-time whether the heat transfer tube is damaged or not. The heat transfer tube of a steam generator for a sodium-cooled fast reactor, includes an inner tube formed with a first material; an outer tube formed with a second material that is in close contact with the inner tube and which has a thermal expansion coefficient less than that of the first material; and a plurality of helium flow grooves formed between the inner tube and the outer tube along a lengthwise direction of the heat transfer tube for flowing helium gas.

Abstract: A steam generation system comprises: an oxygenated water treatment (OWT) sub-system configured to generate water having oxidizing chemistry; a steam generation sub-system configured to convert the water having oxidizing chemistry into steam having oxidizing chemistry; an attemperator or other injection device or devices configured to add an oxygen scavenger to the steam having oxidizing chemistry to generate steam having less oxidizing or reducing chemistry; and a condenser configured to condense the steam having less oxidizing or reducing chemistry into condensed water.

Abstract: With an installation construction method for boiler facilities, the boiler facilities comprise a boiler building configured of a steel structure, and a boiler main unit suspended within the boiler building from the upper portion of the boiler building. A portion of the boiler building is constructed, a portion of the boiler main unit is suspended from the upper portion of the partially-constructed boiler building, and while the remaining steel structure portions are being added to the partially-constructed boiler building so as to construct the boiler building, the remaining portions of the boiler main unit are added to complete the boiler main unit.

Abstract: A debris filter trap to prevent potentially damaging debris carried by the feedwater entering the pressure vessel of a once through steam generator from entering into the section of tubes which are positioned within the confines of an integrally contained economizer of the once through steam generator. The trap will remove foreign material, from the feedwater flow, that is larger than the space between the tubes, and thus prevent debris particles that are large enough to get lodged in the tube spacing from entering the economizer.

Abstract: A steam generator including a steam chamber defining an enclosed fluid chamber with a plurality of tubes passing through the steam chamber, a combustion chamber defining a closed fluid chamber and an air channel coupled to a burner, and a heat transfer section defining a closed fluid chamber and an air passage in fluid communication with a vacuum source, in which the burner generates a heated air mixture, the vacuum source draws the heated air mixture from the combustion chamber air channel, through the steam chamber plurality of tubes and through the heat transfer section air passage so as to heat fluid passing through the heat transfer section, the steam chamber and the combustion chamber fluid chamber.

Abstract: A fluid recirculation system includes an arrangement of a flow control valve located to receive a flow of fluid from an inlet. The system further comprises an economizer inlet mixing device located to receive the flow of hotter fluid from the arrangement of the flow control valve and from a cooler feedwater stream. An economizer inlet mixing device located upstream of an economizer in a supercritical pressure boiler includes a sparger assembly through which a flow of fluid from the waterwall outlet is received, an inlet through which a flow of fluid from a feed stream is received, and a wave breaker assembly through which an outlet stream from the economizer inlet mixing device is directed.

Abstract: An improved boiler that allows distillation of ethanol from a continuous flow of a hydrous feedstock compound, which may be beer or other semi-solid substance. The internal compartment of the boiler is separated into different zones by a plurality of primary baffle plates and secondary baffle plates. The hydrous feedstock compound is heated as it passes from one zone to another zone and ethanol inside the hydrous feedstock compound vaporizes. The ethanol rich vapor is channeled through a collector column and then collected for further processing. The temperature of the hydrous feedstock compound is slightly different from one zone to another zone because of ethanol concentration changes as the hydrous feedstock compound moves from one zone to another. At the last zone, where most of ethanol is removed, the remaining hydrous feedstock compound is removed from the boiler.

Abstract: A waste heat recovery system comprises a steam generator, a processor, a first heat exchanger, and a second heat exchanger. The steam generator generates an original steam using water. The first heat exchanger condensates the first steam and emit water and a second steam from the processor. The second heat exchanger condensates the second steam from the first heat exchanger. The second heat exchanger condensates the second steam from the first heat exchanger leaving water only. The water from the first heat exchanger and the second heat exchanger may be guided into the steam generator or into the first heat exchanger. The second heat exchanger comprises one or more pressure relief valve. The pressure relief valve operates when inner pressure of the second heat exchanger exceeds above a predetermined value.

Abstract: An evaporator including a lower drum, an upper drum, and at least one tube extending between the lower drum and the upper drum. The plurality of tubes have fluid passageways therein extending from the lower drum to the upper drum. A duct is provided having a heating gas passageway provided therein. The at least one tube extends through the heating gas passageway. The fluid passageways define an overall flow path from the lower drum to the upper drum extending in a direction substantially counter-current to an overall flow path defined by the heating gas passageway extending from a gas inlet of the heating gas passageway to a gas outlet thereof.

Abstract: In a steam generator, a flow resistance adjusting unit for a primary cooling water is provided in an inlet nozzle provided at an incoming water chamber or an outlet nozzle provided at an outgoing water chamber.

Abstract: A method of evaporating liquid in a liquid evaporating system having heat exchangers, evaporators, and steam reheaters, includes: preheating condensed water in the heat exchangers; distilling in the evaporators the condensed water from the heat exchangers, wherein the evaporators each has a horizontal plane evaporating chamber at an upper side thereof and a horizontal plane steam heating chamber at a lower side thereof, wherein heating steam is provided from an external boiler to the heating chamber; exchanging heat between the evaporating chamber and the heating chamber using a heat exchange boundary face formed in a concavo-convex shape, wherein the heat exchange boundary face is formed of a metal plate; and reheating in the steam reheaters the steam from the respective evaporators, wherein the reheaters each are coupled to a subsequent one of the heating chambers to serve as a heating source of the subsequent heating chamber.

Abstract: A multistage evaporation system is proposed in which the first evaporator is heated via a jet wet washer with superheated, air-containing waste steam, for example of a drier. The product vapor of the first evaporator stage is fed via a mechanical compressor to a second evaporator stage for heating. The compressor ensures firstly a lowering of the dew point in the evaporator space of the first evaporator stage and secondly a temperature increase of the product vapor fed to the second evaporator stage for heating.

Abstract: A system providing for heat recovery from exhausted flue gas in a steam generator is described comprising a flue gas outlet conduit defining a flow path for flue gas from a flue gas outlet of a steam generator to a flue gas conduit junction point; a flue gas primary conduit defining a flow path for flue gas from the junction to a primary air preheater; a flue gas secondary conduit defining a flow path for flue gas from the junction to a secondary air preheater; wherein a steam generator process fluid heat exchanger is disposed within the flow path of the flue gas primary conduit upstream of the primary air preheater to recover some heat from the flue gas in advance of the primary air preheater. A method implementing the flow principles embodied in such a system is also described.

Abstract: In a steam-heating apparatus in which a heating section formed in a heat exchanger is connected to a steam supply pipe for receiving supply of heating steam and connected also to a condensate-recovering unit for discharging condensate produced as a result of heating, the apparatus includes a steam ejector including a suction chamber connected to the heating section and an inlet for receiving supply of the steam. When the temperature of the heating section or between the heating section and the condensate-recovering unit is dropped by a predetermined value, steam is supplied from the steam supply pipe to the inlet of the steam ejector, and gas in the heating section is sucked into the suction chamber of the steam ejector.

Abstract: In a steam-heating apparatus in which a heating section formed in a heat exchanger is connected to a steam supply pipe for receiving a supply of heating steam and connected also to a condensate recovering unit for discharging condensate produced as a result of heating, the apparatus includes a steam ejector including a suction chamber connected to the heating section and an inlet for receiving supply of steam. When the temperature of the heating section or between the heating section and the condensate recovering unit is dropped by a predetermined value, steam is supplied from the steam supply pipe to the inlet of the steam ejector, and gas in the heating section is sucked into the suction chamber of the steam ejector.

Abstract: In a steam-heating apparatus in which a heating section formed in a heat exchanger is connected to a steam supply pipe for receiving a supply of heating steam and connected also to a condensate recovering unit for discharging condensate produced as a result of heating, the apparatus includes a steam ejector including a suction chamber connected to the heating section and an inlet for receiving supply of steam. When the temperature of the heating section or between the heating section and the condensate recovering unit is dropped by a predetermined value, steam is supplied from the steam supply pipe to the inlet of the steam ejector, and gas in the heating section is sucked into the suction chamber of the steam ejector.

Abstract: A grading system for a pressurized water reactor steam generator secondary side performance that provides a cumulative assessment of tube bundle deposit inventory and characteristics, i.e., scale density and distribution, hard scale collar formation, thermal performance, loose parts management, and steam generator secondary side chemistry performance. Results are summarized in a cumulative quality point average with individual parameter ratings available so that specific performance improvement may be achieved.

Abstract: A vapor generator comprising an evaporator unit, which in turn includes an inner chamber for containing a first fluid in a liquid state, and further includes a preheated liquid inlet and a vapor outlet, the evaporator unit having a heating device therein which can be activated for vaporizing the first fluid contained in the inner chamber to generate vapor. The vapor generator further comprises a preheating tank defining an inner chamber and comprising a liquid inlet for injection of the first fluid in a liquid state in the inner chamber, and a liquid outlet. Moreover, the vapor generator comprises an opened liquid channel connecting the preheating tank liquid outlet to the evaporator unit liquid inlet, and establishing free and continuous fluid communication between the preheating tank inner chamber and the evaporator unit inner chamber.

Abstract: In a steam-heating apparatus in which a heating section formed in a heat exchanger is connected to a steam supply pipe for receiving supply of heating steam and connected also to a condensate recovering unit for discharging condensate produced as a result of heating, the apparatus includes a steam ejector including a suction chamber connected to the heating section and an inlet for receiving supply of the steam. When the temperature of the heating section or between the heating section and the condensate recovering unit is dropped by a predetermined value, steam is supplied from the steam supply pipe to the inlet of the steam ejector, and gas in the heating section is sucked into the suction chamber of the steam ejector.

Abstract: In a steam-heating apparatus in which a heating section formed in a heat exchanger is connected to a steam supply pipe for receiving supply of heating steam and connected also to a condensate recovering unit for discharging condensate produced as a result of heating, the apparatus includes a steam ejector including a suction chamber connected to the heating section and an inlet for receiving supply of the steam. When the temperature of the heating section or between the heating section and the condensate recovering unit is dropped by a predetermined value, steam is supplied from the steam supply pipe to the inlet of the steam ejector, and gas in the heating section is sucked into the suction chamber of the steam ejector.

Abstract: A method of controlling the feedwater flow to the secondary side of a steam generator in a pressurized water nuclear reactor monitors various process variables such as the feedwater and the steam flows and pressures around the secondary side of the steam generator and then generates process signals based upon the process variables. An error signal based upon selected process signals is generated. The error signal is filtered by a deadband filter network for generating a control signal with a deadband. The control signal with a deadband is sent to a proportional-integral controller for generating a demand signal. The demand signal is then sent to an operator such as feedwater valve positioner or a feedwater pump speed controller for controlling the feedwater flow into the steam generator.

Abstract: In one aspect, the invention provides a steam generation apparatus that is liquid fuel fired and addresses conversion of gaseous fuel SIB units to operate with liquid fuel. The invention also relates to a conversion unit for a steam injection boiler, a method for converting a steam injection boiler from gas firing to possible liquid fuel firing and a method for generating steam from a liquid fuel source. The invention employs a fired heater for heating the liquid fuel to a temperature suitable for firing and preheats the water to compensate for the shortfall in heat liberation when a gas boiler is converted to use liquid fuel. In another aspect of the invention, production of steam is achievable consistently by employing step-up heaters with a steam injection boiler. The heaters being connected in parallel to continue heating the water/steam to achieve a higher quality steam over that produced in the boiler while minimizing consideration as to the adverse effects of coil fouling in the boiler.

Abstract: A method and apparatus to conduct 02/CO2 combustion or oxygen-enriched combustion. The boiler exhaust gas passes through a Gas Primer Sector (GPS) combined with the boiler to effect heat transfer to the combustion gas in indirect counter-flow heat exchange. Sharply reduced gas flows result from using largely moisture-free CO2 as diluent for O2 in the combustion gas which allows long residence time at low velocity for maximum heat transfer from the exhaust gas to the combustion gas. Most particulate drops out and most moisture is condensed from the cooled mostly CO2 exhaust gas. The larger portion is blended with oxygen for the combustion gas and reheated and returned to the boiler through the integrated GPS; the smaller portion is cleaned and separated, the CO2 released or recovered. The complete exhaust gas-combustion gas cycle may be 30 to 90 seconds and preferably about 60 seconds.

Abstract: A flow control apparatus for a boiling water nuclear reactor steam dryer is provided. The steam dryer includes at least one discharge plenum. In an exemplary embodiment, the flow control apparatus includes a support member, an elongate perforated plate member coupled to the support member, and at least one positioning member coupled to the support member.

Abstract: In a steam-heating apparatus in which a heating section (2) formed in a heat exchanger (1) is connected to a steam supply pipe (3) for receiving supply of heating steam and connected also to a condensate recovering unit (6) for discharging condensate produced as a result of heating, the apparatus includes a steam ejector (5) including a suction chamber (13) connected to the heating section (2) and an inlet for receiving supply of the steam. When the temperature of the heating section (2) or between the heating section (2) and the condensate recovering unit (6) is dropped by a predetermined value, steam is supplied from the steam supply pipe (3) to the inlet of the steam ejector (5) and gas in the heating section (2) is sucked into the suction chamber (13) of the steam ejector (5).

Abstract: An upper bundle steam generator cleaning, inspection, and repair system including a deployment support device receivable within the steam generator to raise a cleaning device, an inspection device, and/or a tool up to the upper bundles of the steam generator.

Abstract: The invention relates to a method and a steam generator for generating steam, in particular ultrapure steam, by reacting a stoichiometric mixture comprising a fuel, in particular hydrogen, and an oxidizing agent, in particular oxygen, and injecting water into the hot reaction gases, which is distinguished by a high purity of the steam generated.

Abstract: A process for heating steam, wherein(a) steam is obtained by indirect heat exchange between liquid water and a hot gas,(b) the steam obtained in step (a) is heated by indirect heat exchange with the partly cooled hot gas obtained in step (a),(c) additional water is added to the steam obtained in step (a) prior to or during heating the steam in step (b).

Abstract: A flow control apparatus for a boiling water nuclear reactor steam dryer is provided. The steam dryer includes at least one discharge plenum. In an exemplary embodiment, the flow control apparatus includes a support member, an elongate perforated plate member coupled to the support member, and at least one positioning member coupled to the support member.

Abstract: A saturated steam generator which is provided with a heat source for heating water to generate saturated steam and which can be small-sized. A saturated steam generator for generating saturated steam by heating water with superheated steam resulting from being superheated in a heat transmission tube (16) inserted into a heat storage tank (10), characterized by the provision of a saturated steam generator tank (12), wherein in the heat storage tank (10), disposed in a heat storage section composed by having a solid heat storage material and a liquid heat storage material filled therein are a heat transmission tube (16) and a heater (44), which heats the solid heat storage material and the liquid heat storage material, it being arranged that superheated steam resulting from passing through the heat transmission tube (16) is used as a heat source to heat stored water (22) so as to generate saturated steam.

Abstract: A temporary cover is plugged into an open handhole or inspection port in a steam generator or another pressure vessel of a nuclear power plant after bolted covers are removed for maintenance inside the generator or vessel. The temporary cover may be locked to prevent foreign objects from entering the generator or vessel. The cover is vented at inclined angles so that air or gas may pass therethrough but is shielded so that gamma rays, which are the most penetrating type of radiation, are greatly reduced and dispersed away from personnel.