SU1571387A1 - Water-cooled panel of metallurgical furnace - Google Patents

Abstract

The invention relates to metallurgy, to the construction of metallurgical furnaces, in particular to the design of water-cooled elements of the smelting space of these furnaces. The aim of the invention is to increase the reliability of the panel by reducing its warping during heating and cooling and to simplify the panel manufacturing technology. The water-cooled rectangular panel contains at least two spiral channels rigidly fixed with connecting elements and elements for holding the refractory coating. The working part of the channels is made of solid bent pipes arranged with a gap, with adjacent pipes in the corners rigidly connected by profiled sheets, and in straight sections the gap between adjacent pipes is blocked with rods rigidly fixed on one of the pipes. The size of the gap between adjacent pipes is 0.025-0.5 of the outer diameter of the pipes. 1 hp F-ly, 1 tab., 4 Il.

Description

(21) 3978446 / 24-02

(22) (46)

11/15/85

15.06.90. Bksh. No. 22

(71) All-Union Scientific Research, Design and Technological Institute of Electrothermal Equipment

(72) A.D.Litvkov, A, SaKondryukov, N.A., Ivanyutenko, L.I.Kukhareky, V.G. Zavlov, B.B.Pelts, G.I. Orlov, V.P.Davydov , S.D. Sautin, V.I.Bondar, E.I. Arkhipov, I.P. Nechaev and E.M. Ponomarev

(53) 669.187.2.036.538 (088.8)

(56) PCT patent (f 81/00758, cl. F 27 D 1/12, 1981.

For France of France No. 2411380, cl. F 27 D 1/12, 1979.

(54) WATER COOLED PANEL OF METALLURGICAL FURNACE

(57) The invention relates to metallurgy, to the designs of metallurgical furnaces, in particular to the structures of water-cooled elements of the smelting space of these furnaces. The aim of the invention is to increase the reliability of the panel by reducing its warping during heating and cooling and to simplify the panel manufacturing technology. The water-cooled rectangular panel contains at least two spiral channels rigidly fixed with connecting elements and elements for holding the refractory coating. The working part of the channels is made of solid bent pipes arranged with a gap, with adjacent pipes in the corners rigidly connected by profiled sheets, and in straight sections the gap between adjacent pipes is blocked with rods rigidly fixed on one of the pipes. The size of the gap between adjacent pipes is 0.025-0.5 of the outer diameter of the pipes. 1 hp F-ly, 1 tab., 4 Il.

with 58

(L

The invention relates to metallurgy, in particular to the constructions of metallurgical furnaces, in particular to the designs of water-cooled elements of the smelting space of these furnaces.

The purpose of the invention is to increase the reliability of the panel by reducing its warping during heating and cooling and to simplify the panel manufacturing technology.

Figure 1 shows the proposed panel, a general view; figure 2 - then

same, plan view; on fig.Z - section aa in figure 1; figure 4 - section bb in figure 1.

The panel consists of a series of solid metal tubes 1. The inner 2 and outer 3 surfaces of the panel repeat the surface of the furnace shell. The metal pipes of the panel are laid bifilno in the form of two concentric spirals 4 and 5 arranged one inside the other with alternating turns of the spirals. The ends of the 6 spirals, located in the center of the panel, are connected and form

ate

with

00

VI

loop 7 protruding above the outer surface 3 of the panel. The other two ends of the 8 spirals are bent and protrude above the outer surface of the 3 panels. From the outer surface 3 (in the corners) the panel is provided with metal profiled sheets 9 attached to the pipes of the spirals 4 and 5 by welding along the entire contour. The helix pipes 1 are laid with a gap of 10, which is 0.025-0.5 of their outer diameter. In straight pipe sections (section A-A in FIG. 1), the gaps between the pipes are closed with rods 11 (sheets can also be used) attached by welding only to one of the adjacent pipes. Pins 12 are uniformly mounted on the inner surface 2 of the panel to hold the refractory coating and that are formed during the operation of the garnish. In addition, rods 13 are mounted on the outer surface 3 for fastening the panel to the furnace casing. Water is supplied to one of the bent ends 8 of coils 4 and 5 o Water passes through one of the coils, through loop 7 enters the other coil and leaves the bent pipe end

The choice of the gaps between the pipes within 0.025-0.5 of their outer diameter is explained as follows. When the gap between the pipes is less than 0.025 of their outer diameter when assembling the panels, there are particular cases of the inability to install spirals into each other because of the tolerances for the manufacture of these parts, which do not guarantee the normal installation of the coils in one another, the upper limit of the gap between the pipes of 0.5 of their outer diameter is due to the fact that 9 as shown by experiments carried out on experimental panels installed on the heating the stand in the laboratory, with a gap of Mendu pipes of more than 0.5 of their outer diameter, the durability of panels is sharply reduced due to the burnout of sheets in the corners of panels due to insufficient heat removal from the sheets by adjacent water-cooled pipes,

The table shows the data of experts on the durability of panels on a heating stand.

It is known that the durability of panels is determined by the amount of its heat smear or the number of heats, i.e.

heating it during the period of melting and the period of the molten metal in the furnace and cooling down during the intermelting period is simple. Fracture (cracking) occurs in the pipes and sheets of the panel as a result of fatigue stresses from heating (expansion) and cooling (compression) of these elements.

Two types of water-cooled wall panels were tested. The design of the first type of panels is made in the form of two tubular concentric spirals arranged one inside the other, the turns of the spirals are laid with a gap of 0.025-0.5 of their outer diameter, and the gaps in the corners of the panel are closed by profiled sheets welded to each of the two pipes, and straight sections of pipes, the gaps are closed with rods welded to one of the adjacent pipes, i.e. structurally similar to the proposed design. The second type of test panel is a water-cooled cavity consisting of parallel channels, laid with gaps, covered with bridges welded all the way to two adjacent pipes (channels), i.e. structurally similar to the famous panel.

The area of each panel was about 1.5 m, cooling water with a flow rate of 12 me / h was supplied to each panel, the panels were made of pipes with an outer diameter of 7 mm and a wall thickness of 12 mm. The panels were tested on a heating stand that allowed simulating the heat load on the panels up to 100 kW / m, i.e. similarly to the tested panels in real conditions on an electric steel-smelting furnace, they consisted in installing the panel on a heating stand, holding it on the stand for 30 minutes, removing it from the stand, cooling it by cooling the water in it and reinstalling the panel on the heating stand to the first destruction, expressed either in the appearance of a leak, or in a burnout of sheets covering the gaps between the pipes of the panel.

The test results of the panels are presented in the table.

 From the data in the table it follows that when testing panels of the first type

when the gaps between the pipes of 0.5 of their outer diameter were exceeded, the durability of the panels decreased due to burnout of the sheets in the corners of the panels caused by large thermal loads on the sheets and insufficient heat dissipation from them by adjacent water cooled pipes.

When testing the panels of the second type, their durability was found (compared to the panels of the first type) due to the destruction due to high thermal stresses, which are due to the impossibility of pipe channels being displaced relative to each other, which resulted in breaking of the welds to pipes and the appearance of water leaks (with gaps between pipes greater than 0.3 of their outer diameter) and rupture of welds and burnout of sheets (with gaps between pipes greater than 0.3 of their outer diameter).

 The proposed panel works as follows.

When the furnace is in operation, electric arcs irradiate the internal (working) surface of the water-cooled panel. The heat flux from the oven passes through the coating or garnish retained on the panel and is reduced by cooled water flowing in the panel turns.

Under the action of thermal loads, thermal stresses arise in the panel, which, in the presence of continuous

0

five

0

five

0

five

welds in straight pipe sections can lead to pipe breakage and water breakthrough into the furnace. A series of wide experiments on the choice of gaps between the panels of the panel made it possible to find the optimal ratio of the choice of these gaps, which make it possible to increase the reliability of the panel and simplify the technology of its production.

Claims (2)

1.Water-cooled panel of a metallurgical furnace containing at least two spiral channels rigidly fixed with connecting elements and elements for holding a refractory coating, characterized in that, in order to increase the reliability of the panel by reducing its distortion during heating and cooling and simplify the technology the panel is manufactured; the working part of the channels is made of bent pipes arranged with a gap, with adjacent pipes in the corners rigidly connected by profiled sheets, and in straight sections the gap between cm Eich pipes blocked by rods rigidly mounted on one of the pipes. 2. Panel pop.1, characterized in that the size of the gap between adjacent pipes is 0.025-0.5 of the outer diameter of the pipes. 00 15713878 .1 table continuation 1 BUT  6-6 3 / S Figm 2 Figz