SK279470B6 - Device for supplying interchanger, especially steam generator, with secondary water - Google Patents

Abstract

A device for supplying interchanger, in particular steam generator, with the secondary water in which an inlet (1) of the water supply is connected to a distribution tubing (4) to which a distribution manifold (5) is connected. Branches of the distribution manifold run above a nest of tubes (8) of the steam generator's pipes. An outlet pipe (9) arrangement, being led from the distribution manifold, is terminated above the nest of tubes (8) and/or in an interspace of the distribution manifold (8) of the steam generator's pipes.

Description

Technical field

The present invention relates to a steam generator power supply device which is connected to a primary and secondary circuit of a nuclear power plant, and by its suitable design in the interior of the steam generator body allows a significant reduction of the total shutdown time of the nuclear power plant unit. the steam generator body, while facilitating the visual inspection of the supply pipe to prevent leakage, and the consequent undesirable effect of secondary water on the wall of the primary collector, thereby preventing its damage, leading to an increased service life of the unit and prolonged operating time of the nuclear power plant.

BACKGROUND OF THE INVENTION

Up to now, steam generators are known which serve as heat exchangers between the primary and secondary circuits of a nuclear power plant. The steam generator itself is formed by a steam generator body, cigar-shaped, in the interior of which is located the primary collector, the output primary collector, the tube bundle support system and the actual supply pipe. The supply line consists of a supply pipe connected to the central distribution supply line, which is routed in close proximity along the inlet primary collector wall, below the secondary water level, with two horizontal pipes connecting the central supply supply line to the central distribution supply line. in the interstices of the tube bundle of the heat exchanger tubes of the steam generator. A disadvantage of said arrangement of the individual nodes of the steam generator, especially its supply system, is that due to the considerable amount of continuously supplied supply water, at the lower part of the distribution pipeline, at the connection point of horizontal distribution tubes, where the direction and speed of the supply water flow changes leaks or cracks due to cavitation and water erosion. These leaks are the cause of undesirable leakage of secondary water in close proximity to the inlet, primary collector.

The relatively cold feed water, one-sided washing the inlet of the primary collector wall, causes the stress of the material due to uneven temperature load along the perimeter of its wall at the given location, which in extreme cases leads to cracks in the steam collector primary collector wall. operation. A further disadvantage is that it is not possible to perform a visual inspection of the steam generator feed system since the most exposed location, i. j. instead of connecting the horizontal manifolds to the manifold, it is in the lower third of the steam generator body surrounded by a tube bundle. Another disadvantage is that during the repair of the supply pipeline, it is necessary to carry out demanding technological operations that require a long shutdown time of the steam generator and hence of the nuclear power plant block, while simultaneously placing the supply pipeline in a confined space between the pipe bundle makes it difficult to dismantle. .

SUMMARY OF THE INVENTION

These drawbacks are eliminated by a device for supplying the heat exchanger, in particular a steam generator, with secondary water, which consists, on the one hand, of a supply sleeve when caught in the upper part of the steam generator body and on the other hand of a manifold and supply water pipes. SUMMARY OF THE INVENTION The supply water is provided by a manifold, to which a manifold is connected, the branches of which run over the tube bundle of the steam generator heat exchanger tubes, and wherein the manifold is discharged from the manifold through the manifolds / pipe manifolds. or in the space of the tube bundle of the heat exchanger tubes of the steam generator. It is also essential that the free ends of the discharge tubes are equipped with a mixing box. Another principle is that at least one feed water flow rectifier is located below the mixing box.

The advantage of the device for supplying the heat exchanger, especially the steam generator, with secondary water is that by placing the supply line above the steam generator tube bundle it is possible to perform a clear, quick visual inspection of the steam generator supply system and determine the extent of possible damage to this line. unwanted leakage of cold feed water into the space near the primary collector inlet, which causes the stress of the material due to uneven temperature load along the perimeter of the collector wall. This early detection of the technical condition of the supply pipeline prevents cracks in the wall of the primary collector and thus undesirable emergency conditions of the primary circuit of the nuclear power plant, in which the steam generator is connected, which significantly contributes to increasing the unit life. . Another advantage is that during the repair of the supply piping, it is not necessary to perform demanding technological operations by special technological means, which only performs the replacement of damaged parts of the current equipment, in a confined space inside the tube bundle. It is also advantageous that the design of this device allows for very simple assembly and disassembly, thus shortening the assembly times and thus the overall shutdown time of the nuclear power plant block. It is also advantageous that the outflow of the feed water outlet pipe in the upper part of the steam generator body or its outlet just below the level of continuously supplied feed water will improve the boiler water circulation, thus ensuring the required mixing of the supplied feed water with the current boiler water.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, a device according to the invention is shown. 1 is a side view of the steam generator body, FIG. 2 shows a top view of the steam generator body and FIG. 3 is a side view of a manifold with a manifold assembly.

DETAILED DESCRIPTION OF THE INVENTION

The apparatus for supplying a heat exchanger, in particular a steam generator with secondary water, according to an exemplary embodiment of the invention, comprises a supply water supply 1 fixed in the wall of the steam generator body 2, opposite the inlet part 3 of the primary steam generator collector. The feed water inlet 1 is connected to a U-shaped manifold 4, with a manifold 5 connected to the manifold 4, one branch of which is led between the inlet part 3 of the primary collector 4 and the outlet part 6 of the primary collector of the steam generator. The second branch of the manifold 5 is guided around the inlet part 3 of the primary collector, the two branches of the manifold 2 being located and fastened to the support and expansion structure 7 and extending above the tube bundle 8 of the steam generator heat exchanger tubes. From the straight sections of the manifold 5, a set of inverted pipes 9, having the shape of an inverted letter J, is led out into the interspace of the two sections of the tube bundle 8 of the heat exchanger tubes of the steam generator.

A further alternative of this solution is that the free ends of the outlet pipes 9 are equipped with a mixing box 10 consisting of both metal side panels 11 attached to the ends of the outlet pipes 9 and a flow baffle 12 to increase mixing of boiler and feed water.

Claims (3)

PATENT CLAIMS Apparatus for supplying a heat exchanger, in particular a steam generator, with secondary water, comprising a supply sleeve mounted in the upper part of the steam generator body, a manifold and supply water pipes, characterized in that a manifold piece is connected to the supply water inlet (1). (4), to which a manifold (5) is connected, the branches of which run over the tube bundle (8) of the steam generator heat exchanger tubes, and wherein the manifold (5) extends from the manifold (9) over the tube bundle (8) heat exchange tubes and / or in the space of the tube bundle (8) of the steam generator heat exchange tubes. Apparatus for supplying a heat exchanger, in particular a steam generator, with secondary water, according to claim 1, characterized in that the free ends of the discharge tubes (9) are equipped with a mixing box (10). Apparatus for supplying a heat exchanger, in particular a steam generator, with secondary water, according to claim 2, characterized in that at least one supply water flow rectifier (12) is located below the mixing box (10).