The invention relates to a method for evaluation of fouling of passages of a spacer plate (10) of a tubular heat exchanger (11), wherein first, second and third pressure sensors (31, 32, 33) are arranged, the method comprising steps of: (a) during a transient operation phase of the heat exchanger determination of a value over time of Wide Range Level NGL, from the measurements of the first and third pressure sensors (31, 33), and of a value over time of Narrow Range Level NGE, from the measurements of the second and third pressure sensors (31, 33); (b) determination of a value over time of Steam Range Level deviation NGV, corresponding to the NGL from which a component representative of a variation of free water surface in the heat exchanger has been filtered, from the values of NGL and NGE; (c) comparison of the determined value of NGV with a set of reference profiles NGV.sub.i for said transient operation phase of the heat exchanger, each reference profile NGV.sub.i being associated with a level of fouling so as to identify a target reference profile NGV.sub.opt among the reference profiles NGV.sub.i for said transient operation phase of the heat exchanger, which is that closest to the determined value NGV. (d) restored on an interface (3) of the level of fouling associated with the identified target reference profile NGV.sub.opt.

The present disclosure relates to an L-shaped header of a steam generator including a spiral heat transfer tube, and a coupling structure between the L-shaped header and the heat transfer tube, wherein an upper end and a lower end of a heat transfer tube assembly configured with a plurality of heat transfer tubes are vertically formed, and the upper and lower ends of the heat transfer tube assembly are vertically coupled to a bottom side or a top side of the header. Therefore, the heat transfer tubes constituting the same concentric circle may use the heat transfer tubes formed with the same shape, thereby improving the manufacturability of parts and reducing the manufacturing cost.

The present disclosure relates to a drilling device for machining tubes in tube sheets of heat exchangers in a radioactive environment. A retaining plate is clampable in the tubes with at least two retaining fingers on a first side and a first drive, which drives a tool shaft, is arranged on a second side. A tool chuck on a first end side of the tool shaft is connected detachably to the latter, wherein a forward feed of the tool shaft is brought about by a feed device. In addition, the tool chuck is unlockable from the tool shaft by way of an unlocking instrument and the unlocking instrument is controllable by a remote-control device.

The present invention relates to a plate heat exchanger and provides a heat exchanger and a nuclear power plant comprising same, the heat exchanger comprising: a plate unit having multiple plates overlapping one another; a flow path unit, which forms flow paths having fluids flowing therein by processing at least parts of the respective plates; and a detection flow path formed between the multiple plates so as to allow the fluids leaking from the flow paths to flow thereinto and formed so as to detect the leakage of the fluids from the flow paths.

Systems and methods position tools about a flooded nuclear reactor during maintenance outages without overhead support or alignment structures being necessary. systems may include annular clamps for support from a reactor steam dam, a telescoping mast, a motor or other drive to extend or retract the mast, and/or an articulator to hold the payload and move the same about any degree of freedom. The telescoping mast may include several nested sections joined to a drive motor. Several different articulators are useable, including those with separate gearings for rotation about perpendicular axes and self-leveling wrists to orient tools in confirmed positions. Systems can be locally or remotely powered and controlled through powered and communicative connections to move about any position in a reactor annulus or core.

A coolant recirculation system of a nuclear power plant is provided that may include: a reactor vessel configured to accommodate a reactor core and a reactor coolant therein; a steam generator configured to transfer a gas, converted from a liquid phase to a gaseous phase by exchanging heat with the reactor coolant, to a turbine system; a pressurizer configured to control pressure of the reactor coolant in the reactor vessel; a primary system pressure reducing valve located above the pressurizer and configured to open at a predetermined pressure to discharge the reactor coolant into a containment building for rapid depressurization; and a moisture separator connected to the primary system pressure reducing valve to separate moisture. The moisture separator may separate the reactor coolant into a gaseous phase and a liquid phase. Then, the liquid phase reactor coolant may be returned to the reactor vessel to be recirculated.

The group of inventions refers to heat exchange machinery. The device includes a tank with an outlet fitting and a steam source, a deaerator column with a cover and water inlet and vapor blowdown fittings located on the same, containing lower and upper deaeration sections. Each section includes pressure and distribution trays forming a jet chamber in the space between them, and random element packing. Deaeration sections are separated by a hydraulic seal formed by the edge of the upper section pressure tray and the projection connected to the deaerator column cover. The water inlet and vapor blowdown fittings are located inside the hydraulic seal projection with openings in it. The lower edges of the openings are located higher than the upper edge of the hydraulic seal by a value exceeding the sum of overflow height of the coolant over the edge and hydraulic resistance of the hydraulic seal channel. The total cross section of the openings is determined by equality of steam pressure in the blowdown fitting and in the space inside the hydraulic seal projection. This increases the operation reliability.

Various exemplary embodiments of a power conversion system for converting thermal energy from a heat source to electricity are disclosed. In one exemplary embodiment, the power conversion system may include a substantially sealed chamber having an inner shroud having an inlet and an outlet and defining an internal passageway between the inlet and the outlet through which a working fluid passes. The sealed chamber may also include an outer shroud substantially surrounding the inner shroud, such that the working fluid exiting the outlet of the inner shroud returns to the inlet of the inner shroud in a closed-loop via a return passageway formed between an external surface of the inner shroud and an internal surface of the outer shroud. The power conversion system may further include a source heat exchanger disposed in the internal passageway of the inner shroud, the source heat exchanger being configured to at least partially receive a heat transmitting element.

Heat recovery steam generators (HRSGs) including components and systems for reducing thermal stress experienced by manifolds within the HRSGs are disclosed. The HRSG may include a manifold receiving a working fluid of the HRSG, a plurality of piping links in fluid communication with the manifold, and an enclosure surrounding the manifold and the plurality of piping links. The HRSG may also include at least one thermal element positioned within the enclosure. The thermal element(s) may surround the manifold. Additionally, or alternatively, the HRSG may include a supplemental heating system in fluid communication with an interior of the enclosure. The supplemental heating system may include a heater for heating fluid (e.g., air), and an inlet conduit in fluid communication with and positioned downstream of the heater. The inlet conduit may be formed through the enclosure to provide the heated fluid to the interior of the enclosure.

A steam dispersion system including insulation is disclosed. The steam dispersion system may include a steam dispersion tube with at least one opening defined on an outer surface of the steam dispersion tube and a hollow interior. The insulation covers at least a portion of the steam dispersion tube, the insulation defining an opening aligned with the opening of the steam dispersion tube, wherein the insulation meets 25/50 flame/smoke indexes for UL723/ASTM E-84 and has a thermal conductivity less than about 0.35 Watts/m-K (2.4 in-hr/ft{circumflex over ()}2 deg F.). A nozzle defining a throughhole may be placed within the opening of the steam dispersion tube, the throughhole being in fluid communication with the hollow interior of the steam dispersion tube to provide a steam exit.