RU2380636C1 - Heat exchanger - Google Patents

Abstract

FIELD: heating systems.

SUBSTANCE: heat exchanger consists of bank of heat exchange coil tubes arranged in the form of platen, the ends of which are fixed in tube sheets; every two adjacent heat exchange coil tubes are attached to each other by means of shaped straps equally spaced as to platen height in staggered order; at that, shaped straps and fasteners have the same material as the tubes.

EFFECT: design with proposed tube bank design will allow obtaining small-sized heat exchanger meeting requirements for reliability, manufacturability, erection at high specific thermal stresses of occupied volume of nuclear power plant.

7 dwg

Description

The invention relates to a heat exchange technique and is intended for use as a small-sized heat exchanger in the composition of a high pressure separator-superheater (SPP) of a steam generating nuclear power plant (NPP) operating on a liquid metal coolant in the mode of variable loads.

A single-threaded tubular coil is known, mainly for the convective chamber of a tubular furnace, containing rows of straight pipes arranged in a checkerboard pattern and connected at the ends by bends with a bend angle of 180 °, and the extreme pipes of each row are equipped with additional bends, the axes of which are located in the row plane and the angle their bend is determined from the corresponding mathematical expression [1.].

The disadvantage of this technical solution is the deterioration of the heat transfer process between heating and heated fluids with an increase in the depth of the tube bundle due to an increase in thermo-hydraulic resistance to the flow of the moving coolant and, as a consequence, a decrease in the resource of reliable operation of the structure, since the large temperature head between the inlet and outlet of the coolant leads to very significant damage at the contact points of the metal pipes and their supporting structures.

A shell-and-tube heat exchanger is known, comprising a bundle of heat exchange tubes and intermediate support devices in the annulus, made in the form of rings with spacing elements between the pipes, each supporting device additionally containing a pair of tie plates with holes for the pipes, and a ring with spacing elements is placed between the plates, when this spacing elements are made in the form of strips of elastic material [2.].

The disadvantage of this technical solution is the relatively low intensity of heat transfer between the heating and heated fluids in the design of the heat exchanger as a whole and, as a result, the low values of the output steam content when used as a modular heat exchanger, for example, as part of a high-pressure SPP steam generating ship nuclear power plant.

The technical result of the invention is to ensure maximum compactness of the tube bundle of the heat exchanger and to achieve a high degree of heat transfer efficiency due to the layout of the heat removal surface itself during operation, to increase the resource of reliable operation of the heat exchanger design at high specific heat voltages of the volume occupied by it.

The specified technical result is achieved by the fact that in a heat exchanger consisting of a bundle of heat-exchange coil pipes arranged in the form of a screen, the ends of which are fixed in tube boards, every two adjacent heat-exchange coil pipes are fastened together with profile overlays spaced apart along the height of the screen in a staggered arrangement moreover, profile linings and fasteners have the same material as pipes.

The essence of the invention is illustrated by drawings, where

figure 1 shows a longitudinal section of a heat exchanger;

figure 2 is a cross section along AD;

figure 3 is a longitudinal section of a heat exchanger module;

figure 4 shows a bunch of heat-exchange coil pipes;

figure 5 shows a bunch of heat-exchange coil pipes with wiring bends;

figure 6 shows the profile lining in the context;

7 shows a portion of a bundle of heat-exchange coil pipes with profile plates.

The heat exchanger comprises a housing 0 with a lower (upper) cover 1, nozzles for the inlet 2 and outlet 3 of the heating medium, inlet 4 and outlet 5 of the pumped liquid (wet steam), all nozzles having a chamber 6 for distributing heat-exchanging liquids with a corresponding cover 7, tube boards 8 to which modular 9 heat exchangers are connected with pipes 10 and 11, 12 and 13 by means of pipelines, and modular 9 heat exchangers relative to the housing 0 are spaced apart by spacers 14. Each modular 9 heat exchanger has an inlet 15 and an outlet 16 heat Itel, the chamber of the inlet 17 and the outlet 18 of the heated fluid, while the chambers of the inlet 17 and the outlet of the heated fluid have tube boards 19 and 20, respectively, to which the bundle of heat-exchange coil pipes 21 is attached, the inlet chambers 15 and the outlet of the coolant 16 have perforated tube boards 22 and 23 respectively. The bundle of heat-exchange coil pipes 21 consists of screens assembled from coil pipes, which are successively located in one plane in straight sections, and the bent sections are laid out in one direction from the plane of the arrangement of straight sections, each pipe having a wiring in different directions. Straight sections of pipes have profile plates 24 and 25, interconnected by rigid steel ties 26, and profile plates 24 and 25 are spaced apart along the height of the screens in a staggered arrangement.

The heat exchanger operates as follows.

The heating coolant enters through the nozzle 2 into the distribution chamber 6, from where it enters the nozzle 10 of the modular 9 heat exchanger through pipelines (not shown), into the distribution chamber 15 and through the perforation of the board 22 into the annular space of the tube bundle 21. Then, the coolant enters through the perforation of the board 23 into chamber 16, from where it goes through the pipe 11 and through the pipe through the pipe 3. The heated liquid (wet steam) enters through the pipe 4 into the distribution chamber 6, from where through pipelines (not shown) to the pipe 12 of the modular 9 heat exchanger, then to the distribution chamber 17 with the heat exchanger coil pipes 21 entering the cavity of the beam, into the chamber 18, from where it passes through the pipe 13 through the pipelines to the chamber 6 and exits through the pipe 5. The fastening design allows reliable spacing of the pipes and eliminates grinding of the pipe metal.

The design of the heat exchanger of the proposed type will make it possible to use it as a modular heat exchanger with the most compact tube bundle of a steam generating ship nuclear power plant operating on a liquid metal coolant under variable load conditions that meet the requirements of reliability, manufacturability, installation, at high specific heat voltages of the occupied volume.

Link

1. Tsinkalov G.P. et al. Single-line tubular coil. SU. Patent No. 1386637, C10G 9/20. Priority - 01/07/86. Publ. Bulletin of inventions No. 13. 04/07/1988 - an analogue.

2. Filimonov M.I. Shell and tube heat exchanger. SU. A.S. No. 1232924. F28F 9/02.

Priority - 12/30/84. Publ. Bulletin of inventions No. 19. 05/23/1986 - a prototype.

Claims (1)

A heat exchanger consisting of a bundle of heat exchanger coil pipes arranged in the form of a screen, the ends of which are fixed in tube boards, characterized in that every two adjacent heat exchanger coil pipes are fastened together with profile overlays spaced apart along the height of the screen in a checkerboard arrangement, and profile overlays and fasteners have the same material as the pipes.

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