CN2415329Y

CN2415329Y - Internal cover of silicon steel circular annealing furnace

Info

Publication number: CN2415329Y
Application number: CN 00229231
Authority: CN
Inventors: 卓均之; 吴佑明; 范崇显
Original assignee: Wuhan Iron and Steel Group Corp
Current assignee: Wuhan Iron and Steel Group Corp
Priority date: 2000-02-14
Filing date: 2000-02-14
Publication date: 2001-01-17
Anticipated expiration: 2010-02-14

Abstract

The utility model relates to an internal cover of a silicon steel circular annealing furnace, which is a heat-resisting stainless steel internal cover served in environments of ultra-high temperature media, and is used for the annealing protection of silicon steel rings. The internal cover is composed of an end plate, an upper shell, and a lower shell. The utility model is characterized in that the burning loss section of the lower shell is additionally provided with a binding band which is welded on an external ring about 30 to 80 mm from the lower shell to the lower bottom margin; the thickness of the external ring is same as the thickness of the upper shell, and the width is 110 to 150 mm. The internal cover of the utility model delays the burning loss of the lower shell which does not need be changed in the service life period of the circular annealing furnace, and the service life of the internal cover is extended.

Description

Silicon steel ring annealing furnace inner cover

The utility model relates to a kind of silicon steel ring annealing furnace inner cover, is a kind of heat-resistance stainless steel inner cover of being on active service in the superhigh temperature media environment, is used for silicon steel ring annealing furnace silicon steel volume Annealing Protection.

That Wuhan Iron and Steel Plant in 1993 is built at home first, third place in the world seat silicon steel ring annealing furnace (ROF), be from Japanese Nippon Steel introduce have energy-conservation, continuous production, take up an area of less, the silicon steel of advantage such as control is rolled up annealing furnace automatically.And the ROF inner cover is the key equipment that orientation silicon steel is carried out the high annealing protection, is the welding structural element of internal diameter 2200mm * 2270mm, and material is the YUS701 Austenitic heat-resistance stainless steel that Nippon Steel produces, 3.05 years average lives.Its weak point is that the operation back circle " groove " occurs at the position that white silica sand, burner hearth air and lower shell have a common boundary under the inner cover high temperature, more and more darker with inner cover operation " groove ", the compression of lower shell is also more and more serious simultaneously, in its time limit in service life, must switch the high bottom cylindrical shell of about 300mm, about 70,000 yuan of its price for repairing, and influence ordinary production.

The purpose of this utility model is to avoid the generation of above-mentioned " groove " and the bottom of switching lower shell, and provides a kind of simple in structure, and manufacturing process is easily gone, the inner cover of long service life.

The utility model has designed a kind of silicon steel ring annealing furnace inner cover to achieve the above object, constitute by end socket (1), upper shell (2), lower shell (3), it is characterized in that being provided with band (4) at lower shell, band is welded in the outer ring of lower shell apart from bottom 30～80mm, its thickness and upper shell uniform thickness, width 110～150mm.

The utility model inner cover is mainly as the inner cover of silicon steel volume annealing furnace, and according to the silicon steel production technology requirement, inner cover need satisfy silicon steel and twist in 650～1200 ℃ of insulations 60～70 hours, and the annealing cycle is 140～160 hours job requirement, and protective gas is H in the inner cover ₂: N ₂=3: 1, gas pressure 0.25MPa, it is the burner hearth of combustion medium that the inner cover outside is in coal gas, and the about 110mm in inner cover bottom inserts the interior sealing of white silica sand of table, therefore requires inner cover should have quite high creep rupture strength, oxidation-resistance property and media-resistant corrosive power.Be covered with band in the utility model, effect has two: one, changed the gas or the reaction gas effusion back flow direction of releasing owing to be provided with band by the cover inner bottom part, cover on use suffered the temperature point effect and the dielectric corrosion that release gas or reacting gas generation burning exothermic reaction in making and weaken, thereby reduce scaling loss.Its two, scaling loss occurs in band rather than lower shell, thereby lower shell do not have obvious groove, and since in the following white silica sand that inserts table of lower shell the sealing degree of depth differ, about 80～130mm is wide for the scaling loss section, so the band width selects 110～150mm.Lower shell because of inserting in the white silica sand, be not subjected to scaling loss, corrosion, thereby band needn't weld in limit portion apart from the bottom side portion of bottom 30～80mm.Band adopts the YUS701 steel, and by apolegamy high-carbon high-alloy welding rod, preferred weld technology guarantees welding quality and can improve 5 times of work efficiency that weld seam adopts austenite (γ)+primary carbide (C ₁) duplex structure, effectively avoided the weld seam fire check to produce, guarantee the high-temperature behavior of weld seam again.

The utility model silicon steel annular furnace inner cover has following advantage:

1, covers in the life cycle because lower shell bottom scaling loss corrosion generation groove and distortion in before the utility model and need to switch the average 1.26 times/platform of bottom scaling loss section.The utility model inner cover is simple in structure, only need set up band, and manufacturing process is easily gone, in cover on and need not switch lower shell scaling loss section in its cycle in service life, save cost, save maintenance cost.

2, long service life.Be provided at the statistics that 53 ROF inner covers are used in wide field according to Japanese Nippon Steel, switch the average 1.26 times/platform in bottom, comprise and switch 3.05 its average lives of bottom, adopt average 4 years of service life of the utility model inner cover, prolonged the service life in 1 year.

3, low cost of manufacture.By the 900000 yuan/platform of silicon steel ring annealing furnace inner cover that Nippon Steel introduces, the utility model inner cover manufacturing expense is 400,000 a yuan/platform, saves 500,000 yuan/platform of construction investment, and life-saving 1 year, remarkable in economical benefits.

Further specify the utility model silicon steel ring annealing furnace inner cover with accompanying drawing below.Fig. 1 is the utility model structural representation.

(1) is that end socket, (2) are band for upper shell, (3) for lower shell, (4) among the figure.

The utility model is described in further detail in conjunction with the embodiments:

Embodiment 1: make the novel inner cover of the utility model silicon steel annular annealing, structure as shown in Figure 1, constitute by end socket, upper shell, lower shell, lower shell is provided with band, with the fillet welding mode it is welded in the external circle of lower shell, band and upper shell uniform thickness, width are 120mm, and band is apart from lower shell base 50mm.Make 3 inner covers, under the Wuhan Iron and Steel Plant ultra-high temperature condition, on average be on active service 4.2 years, lower shell does not have obvious groove in the operating period of silicon steel annular furnace, need not switch lower shell fully, the inner cover of making than Japanese Nippon Steel prolongs 1 year service life, save overhaul cost, improved silicon steel output, obtained tangible economic benefit.

Embodiment 2: make the utility model silicon steel ring annealing furnace inner cover, and preparation method such as embodiment 1, there is band the lower shell outer ring, is welded in the lower shell bottom with the fillet welding mode, and band and upper shell uniform thickness, width are 140mm, and band is apart from lower shell base 30mm.Make 3 inner covers, be on active service at Wuhan Iron and Steel Plant, operating position is good in the silicon steel annular furnace, the silicon steel steady quality.

The utility model silicon steel ring annealing furnace inner cover, the inner cover that the employing sand that is particularly suitable for being on active service under the superhigh temperature media environment seals.

Claims

1, a kind of silicon steel ring annealing furnace inner cover, be made of end socket (1), upper shell (2), lower shell (3), it is characterized in that being provided with band (4) at lower shell, band is welded in the outer ring of lower shell apart from bottom 30～80mm, its thickness and upper shell uniform thickness, width 110～150mm.