CN1093307A

CN1093307A - Grate cast process for hot blast stove of blast furnace

Info

Publication number: CN1093307A
Application number: CN 94105183
Authority: CN
Inventors: 李强勇; 兰戊成
Original assignee: No3 Casting Plant Multiple-Producing Enterprises Co Baoto Steel And Iron Co
Current assignee: No3 Casting Plant Multiple-Producing Enterprises Co Baoto Steel And Iron Co
Priority date: 1994-05-16
Filing date: 1994-05-16
Publication date: 1994-10-12
Anticipated expiration: 2014-05-16
Also published as: CN1034110C

Abstract

The present invention relates to the casting technique of a kind of blast funnace hot blast stove, belong to the metallurgical casting technology with fire grate.The present invention adopts rigid flask, the wooden full pattern that has half hole, surrounding is formed whole full pattern with the metal form that has half hole, surrounding, cooperate moulding with the live metal core print, pattern vertically plays sample, following core print die cavity and the common positioning core of porous sheet iron loam cake are guaranteed the required precision of grate pitch of holes tolerance.Fire grate moulding and sheet iron loam cake are general clay-bonded sand with sand, and fuse adopts resin sand, rationally uses material.Its advantage is only to need just can produce the fire grate that satisfies high-precision requirement by casting process, need not process boring, has reduced production cost, has kept the casting casting skin of grate internal surface of hole, can be anti-oxidation and high temperature resistant, thus prolonged service life of fire grate.

Description

Grate cast process for hot blast stove of blast furnace

The present invention relates to a kind of fire grate casting technique, be specially adapted to the casting technique of blast funnace hot blast stove usefulness fire grate in the metallurgical industry.

The fire grate that blast funnace hot blast stove uses is that gather in a kind of vertical hole, the accurate heavy castings of position, hole dimensional requirement, and a complete set of fire grate foundry goods has multiple external shape, its internal structure promptly comb hole shape, size, the complete socks of spacing.Required precision is that two adjacent holes centre-to-centre spacing allowable tolerances are positive and negative 1 millimeter, and ten hole centre-to-centre spacing allowable tolerances of accumulative total are positive and negative 3 millimeters.Its casting technique there have been a lot of improvement in recent years, but mostly have been to seek reasonable plan, under the prerequisite that does not influence fire grate serviceability and life-span, improved hot-blast stove efficient to reduce comb hole plug-hole number from fire grate structural design aspect.Improvable result makes the fire grate structure more complicated often, thereby has increased the difficulty of casting technique.

At present, the manufacturer of some fire grates, in order to reach the requirement of pitch-row tolerance, the operation of generally taking is to cast out blank, machine tooling boring on the back.This method not only production cost height, labour intensity is big, and the comb hole is drilling processing, and internal surface of hole loses one deck can anti-oxidation, resistant to elevated temperatures casting casting skin, thereby has influenced fire grate service life at high temperature greatly.

A patent application of China Anshan Iron and Steel Company, its application number is 90216763.4, notification number CN2091190U, December 25 1991 day for announcing, be to utilize a kind of compound apperance of the casting of locating orifice plate that has, its base plate is composited by wooden model and hard locating hole, and it relies on orifice plate machinery location, location, and core print clamped in the orifice plate, with wood screw the three is clenched again and reinforce.Adopt this compound apperance can make the core print position error be no more than 0.5 millimeter, thereby realized the accurately purpose of location of core print.But the core print of this compound apperance is fixed together with template, and is careless slightly when moulding plays sample, and it is bad that the die cavity of core print is risen, and can only guarantee the accurate positioning of fire grate one side, and is difficult to satisfy the requirement of the pitch-row tolerance of comb hole another side.

The objective of the invention is to overcome above-mentioned the deficiencies in the prior art, a kind of new casting technique has been proposed, can directly cast out the comb hole of fire grate, can not only keep comb internal surface of hole casting casting skin, and can make two adjacent holes centre-to-centre spacing of fire grate allowable tolerance and accumulative total allowable tolerance reach specification requirement fully.Simplify production process, shortened the production time, reduced production cost, prolonged service life.

Blowhole fire grate casting technique of the present invention is: adopt rigid flask, have the wooden full pattern in half hole, surrounding and the whole full pattern of the porous metals template composition that has half hole, surrounding and cooperate moulding with the metal core print, produce core print die cavity under fire grate die cavity and the comb hole, pattern vertically plays sample; The following core print that will have the cylinder resin sand fuse of the upper and lower core print of cone after oven dry, the roasting inserts down in the core print die cavity one by one, the corresponding porous sheet iron of its cope print vertical sleeve lastblock and porous metals template is made one deck molding sand firm by ramming and is made loam cake on sheet iron.The following core print die cavity produced of the sheet iron loam cake that compresses of rramming and integral entity cooperates position and the spacing that fixes the resin sand fuse up and down, to guarantee to cast out the spacing tolerance in comb hole like this.Running gate system is taked the semiclosed cast gate of rising pouring, parallel cast.

Attach metal form and the sheet iron of loam cake and the moulds of industrial equipment that the metal core print is processing and fabricating on whole full pattern, on metal form and sheet iron, hole by designing requirement processing, the size of metal pattern plate hole should be pressed fit tolerance and can clamp into the metal core print, and the size in sheet iron hole should be pressed the cope print that fit tolerance can be inserted in the resin sand fuse.The hole that metal form and sheet iron are corresponding up and down is a concentric circles, its two center of circle overlaps with resin sand core subcenter line and is vertical with two discs, adjacent holes must be skillful in positive and negative 1 millimeter apart from tolerance, and ten pitch-row tolerances of accumulative total must be skillful in positive and negative 3 millimeters, to guarantee the accurate requirement of fire grate foundry goods pitch-row.

Metal form and wooden full pattern all have half hole, surrounding, and appearance and size is just the same.Metal form and wooden full pattern are superimposed together during use, make both surrounding half hole consistencies from top to bottom, and tightening up with screw is a whole full pattern.

The metal core print be by cylinder and up and down cone three parts constitute, its cylinder diameter is slightly less than the diameter of metal pattern plate hole, meets the requirement of tolerance movingly, cylinder height is identical with metal form thickness; Shape and size of cone are consistent with the following core print of resin sand fuse under it; Diameter of cone and cylinder joint is slightly less than the aperture of sheet iron on it, meets the requirement of tolerance movingly.

The present invention compared with prior art has following characteristics:

1. adopt the metal form and the sheet iron that are drilled with the high accuracy fabrication hole to cooperate moulding with the live metal core print, accurately the casting technique of the sub-position of fixing resin core has been guaranteed fire grate pitch-row tolerance grade, thereby has been guaranteed the quality requirement of fire grate foundry goods.

2. adopt the whole full pattern, the pattern that have half hole, surrounding vertically to play sampling technology, not only make each half hole, fire grate foundry goods surrounding and appearance and size accurate, save the consumption of a part of resin sand, and whole full pattern can repeatedly use suitable batch production.

3. adopt core print die cavity technology under the manufacturing of live metal core print, in playing the sample process, core print can be stayed in the die cavity, type to be repaiied, take out core print again after rinsing coating, be unlikely bad core print chamber like this, and core print can use repeatedly.

4. adopt rigid flask and loam cake sheet iron to make the fire grate casting technique, misplace in the time of can avoiding the multiple mould mould assembling, simple, convenient.

5. fire grate die cavity and the used molding sand of sheet iron loam cake are general clay-bonded sand, and fuse adopts the technology of resin sand, is rationally to use material, has both reached specification requirement, can reduce cost again.

In a word, advantage of the present invention is: only just can produce the fire grate qualified products that the blast funnace hot blast stove that satisfies high-precision requirement is used by casting process, need not process boring, reduced production cost, the casting casting skin that has kept the comb internal surface of hole, this layer casting skin has anti-oxidation, high temperature resistant effect, thereby prolonged the service life of fire grate greatly.

Below in conjunction with accompanying drawing the present invention is further described:

Description of drawings:

Fig. 1 is whole full pattern vertical view;

Fig. 2 is Figure 1A-A cutaway view;

Fig. 3 is the casting technique schematic diagram;

Fig. 4 is Fig. 3 B-B cutaway view.

During moulding, earlier wooden full pattern 2 is placed on the platform, metal form 3 places on the wooden full pattern 2, make both half hole, surrounding, 13 consistencies from top to bottom, and be whole full pattern 1 with screw is fastening, then live metal core print 5 pincers are gone in the metal pattern plate hole 4, again rigid flask 11 is entangled whole full pattern 1, make surrounding institute spacing position symmetrically, after back-up sand is made firm by ramming and produced fire grate die cavity 10, whole mould turnover, push down the molding sand that leans on whole full pattern 1 limit with four models, pattern vertically plays whole full pattern 1, and metal core print 5 is stayed in the core print die cavity 12, wait to have rinsed coating, one by one metal core print 5 is taken out kiln drying on the fire grate die cavity of producing again after fixing die cavity, roasting.As shown in Figure 3, resin sand fuse 7 is inserted in the following core print die cavity 12 one by one, and sheet iron 6 is enclosed within on the cope print of resin sand fuse 7 behind the kiln discharge, on sheet iron 6, make one deck clay-bonded sand 8 again firm by ramming and make loam cake.

During cast, press foundary weight, put cast gate 9 in order and carry out casting on flat, promptly get the fire grate foundry goods behind the lift.

The fire grate that the blast funnace hot blast stove that adopts casting technique of the present invention to produce is used reaches positive and negative 0.5 millimeter through surveying its adjacent two hole center distance tolerances, and accumulative total ten hole center distance tolerances reach positive and negative 1.5 millimeters.

Claims

1, a kind of blast funnace hot blast stove casting technique of fire grate, it is characterized in that adopting rigid flask [11], have the wooden full pattern [2] in half hole, surrounding [13] and have the whole full pattern [1] that the porous metals template [3] in half hole, surrounding [13] forms and cooperate core print die cavity [12] under moulding fire grate die cavity [10] and the comb hole with metal core print [5], pattern vertically plays sample, to have on the cone after the oven dry roasting, the following core print of the cylinder resin sand fuse [7] of following core print inserts down in the core print die cavity [12] one by one, its cope print vertical sleeve lastblock and the corresponding porous sheet iron of porous metals template [3] [6], on sheet iron [6], make one deck molding sand [8] firm by ramming and make loam cake, adopt the direct casting of casting on flat method.

2, casting technique according to claim 1, the hole that it is characterized in that porous metals template [3] and porous sheet iron [6] is the processing drilling, two adjacent holes centre-to-centre spacing of its required precision allowable tolerance is skillful in positive and negative 1 millimeter, and ten pitch-row allowable tolerances of accumulative total are skillful in positive and negative 3 millimeters.

3, according to claim 1,2 described casting techniques, it is characterized in that the corresponding up and down hole of metal form [3] and sheet iron [6] is a concentric circles, the central lines of its two center of circle and resin sand fuse [7], and vertical with two disks.

4, casting technique according to claim 1, it is characterized in that metal core print [5] be by cylinder and up and down cone three parts constitute, its cylinder diameter is slightly less than the diameter of metal pattern plate hole [4], meets the requirement of tolerance movingly, and cylinder height is identical with metal pattern plate hole [3] thickness; Shape and size of cone are consistent with the following core print of resin fuse [7] under it; Diameter of cone and cylinder joint is slightly less than the aperture of sheet iron [6] on it, meets the requirement of tolerance movingly.