SK6862002A3 - Steam producer feed junction - Google Patents

Abstract

The present invention relates to a steam generator feeding node comprising an enclosed chamber (1) with inlet water pipes (2), built-in pipe connections (4) with shaped pipes ((5) inserted therein. The shaped pipes (5), being provided on their circumference with channels (6), pass through the enclosed chamber (1) and have their outlet in outer space extending about the enclosed chamber (1), whereby the ratio of said channel (6) cross sections and internal cross section of the shaped pipe (5) ranges within 0.7 to 1.8.

Description

Technical field

The invention relates to a steam generator power node, in particular a horizontal design for nuclear power plants.

BACKGROUND OF THE INVENTION

The supply water distributions within the steam generators, in particular of the horizontal design for nuclear power plants, are provided either inside the bundle of heat exchanger tubes or above the bundle of heat exchanger tubes.

In the case of distributions carried out inside the pipe bundle, this is a solution with one horizontal pipe provided with outflow sockets and connected to the supply supply pipe. The horizontal, generally very rigid pipe is firmly fixed to the support system inside the steam generator and thus also satisfactorily secured against vibration. However, this embodiment of the distribution system has the disadvantage that it is inaccessible and thus irreparable. This finally showed a number of practical experiences.

The supply water distributions in the design above the tube bundle inside the horizontal steam generator are principally provided with one or two horizontally oriented supply pipes connected to the supply water supply and the outgoing groups of supply water supply pipes that are introduced into the longitudinal i " of the tube bundle and connected to either the perforated water outlet pipes or to one or more chambers with openings which are again located in the longitudinal gaps in the tube bundle.

In the case of the flow box distribution chambers in the form of a flow box with a rectifier installation of the feed water flow, there is no mixing of cold supply water with hot water from the outside of the chambers - the box in the box, but only from outside the box. super-emergency power supply, where very cold water, heat shocks with little favorable response on heat exchanger tubes are transported to the steam generator through one and the same distribution system.

Image overview

An exemplary embodiment of a generator power node is shown in the attached figure.

DETAILED DESCRIPTION OF THE INVENTION

In a horizontal steam generator, a bundle of horizontally oriented heat exchanger tubes is disposed so as to form several vertically oriented gaps along its length. In these gaps are closed chambers 1 connected to the water inlet pipe 2 and provided with outlet openings 3 to which are connected the sockets 4 with built-in shaped tubes 5 provided on the outer circumference in the exemplary embodiment with six channels 6 and opening the other end into the outer space around of the closed chamber 1 in such an arrangement that the ratio of the cross-sections of the channels 6 formed on the circumference of the shaped tube 5 and the inner cross-section of the shaped tube 5 is in the exemplary embodiment 1.1. In the area of the relative cross-sections thus performed, both the super-emergency feed of the steam generator with very cold water and the start-up of the steam generator under normal operating conditions with the supply of cooler feed water than the water temperature around the enclosed chambers 1 and thus around the tube bundle both mix both waters. in the space of the closed chambers 1 and the pipe bundle, the warmer feedwater then flows in comparison with the supply water temperature of the feed system and the water inlet pipes 2. This leads to suppression of thermal shocks on the pipe bundle tubes and contributes significantly to long term integrity of the steam generator heat exchangers .

SUMMARY OF THE INVENTION

These drawbacks are eliminated by a steam generator supply node formed by a closed chamber with water inlet ducts and outlet openings provided with sockets with an embedded shaped tube provided on the outer perimeter with at least two channels and opening into the outer space around the closed chamber with the other end in such an arrangement that the circumference of the shaped tube and the inner cross section of the shaped tube is in the range of 0.7 to 1.8.

Advantageously, in such a cross-sectional arrangement, the very cold feed water flowing in the superheater feed of the steam generator or the relatively cold feed water flowing in when starting the steam generator through the hot water inlet ducts 2 enclosed with the hot water inside the enclosure 1 is mixed first. 1. and sucked in the interior of the shaped tubes 5. Thus, warmer water always emerges from the nozzles 4 than the incoming feed water and the tube bundle tubes of the steam generator are not exposed to large thermal shocks from the exit water of the nozzle 4. This ultimately contributes to ensuring and thus to strengthen the nuclear safety of the nuclear power plant.

Claims (1)

PATENT CLAIMS A steam generator feed node formed by a closed chamber with water inlet ducts and outlet openings provided with sockets with an embedded shaped tube provided on the outer circumference with at least two channels and a second end opening into the outer space around the closed chamber, characterized in the circumference of the shaped tube 5 and the inner cross-section of the shaped tube 5 is in the range of 0.7 to 1.8.