Background technology
Stove is widely used in metallurgy and mechanical industry at the bottom of the roller, is the critical process equipment of continuous casting and rolling production line, and its furnace roller is asking heated workpiece to rotate in high temperature, is beneficial to the processing of workpiece.Domestic continuous casting and rolling production line furnace rollers of roller bottom furnace major part is from external integral inlet, and the furnace roller of import adopts the winding of refractory fibre rope to add fire-resistant spraying paint or adopts two kinds of methods of refractory castable vibrating forming to manufacture.The subject matter that exists is at present: (1) adopts the winding of refractory fibre rope to add the furnace roller that fire-resistant spraying paint is made, the manufacture technology complexity, the furnace roller intensity of making is low, anti-shake performance is poor, the non-refractory sweep of gases, work-ing life is low, and must toast before using, investment is big, and floor space is also big; (2) furnace roller that adopts refractory castable to make, manufacture technology is simple, needn't toast before using, and the main component of used refractory castable is Al
2O
3, SiO
2, CaO, TiO
2, ZrO
2, Na
2O, K
2O etc.But bursting in use often appears in above-mentioned furnace roller, influences the work-ing life of furnace roller, and have only about 6 months work-ing life.
Summary of the invention
Technical problem to be solved by this invention provides a kind of refractory castable that is used for furnace rollers of roller bottom furnace that is difficult for bursting.
The technical scheme of technical solution problem of the present invention is a kind of refractory castable that is used for furnace rollers of roller bottom furnace, and it is to be made by the component of following proportioning, and measure unit is a weight part:
Electrofused mullite granularity≤3mm 20-45
Flint clay granularity 1-5mm 0-30
Mullite granularity≤200 order 10-20
Trichroite granularity≤5mm 10-25
Kyanite granularity≤180 order 5-10
Ultrafine silica powder granularity≤5 μ m 2-3
Alumina powder granularity≤5 μ m 5-8
High-alumina cement 4-5
Stainless Steel Fibre 2-4
Explosion-proof fiber 0.1-0.15
Tripoly phosphate sodium STPP 0.15-0.3
Water 7.5-10
Described high-alumina cement is A80.
Described Stainless Steel Fibre is the Stainless Steel Fibre of long * wide * high (mm) 20 * 1 * 0.5.
Described explosion-proof fiber is in the pyroprocess, adds a kind of additive in the mould material for ease of steam discharge in time in furnace roller prevents explosion, and its fusing point is 110 ℃-160 ℃.
In order to improve thermal shock resistance, except having selected for use less mullite of thermal expansivity and flint clay as the aggregate, key is the trichroite that has added 10~25 weight parts.The adding trichroite can significantly improve the thermal shock resistance of mould material.In order to obtain excellent anti-spalling, prevent to burst into the stove initial stage, added the explosion-proof fiber of larger proportion.In order to improve intensity, add the Stainless Steel Fibre about the 2-4 weight part.Silicon oxide and alumina powder generate the staggered mullite crystal of needle-like when high temperature, also can effectively gain in strength.
Adding the high-alumina cement wedding agent is to have enough normal temperature strengths in order to guarantee after the moulding.Shrink in order to offset high volume, add the aquamaine stone flour of 5~10 weight parts and make swelling agent.Have enough flowabilities when guaranteeing moulding so that moulding except adding ultrafine silica powder and alumina powder, has also been added tripoly phosphate sodium STPP and made water reducer.
The present invention compared with prior art, mould material has good flowability, is convenient to the moulding of furnace roller.Because furnace roller anti-spalling and thermostability are very good, can adapt to the rapid variation of temperature in the stove at the bottom of the roller, high-temperature flue gas there is higher resistivity, can reach more than 1 year the work-ing life of furnace roller.Various materials used in the present invention all can be bought from the market simultaneously, have reduced the production cost of furnace roller.
Embodiment
Non-limiting examples is described below:
Furnace roller preparation method: earlier aquamaine stone flour, ultrafine silica powder, alumina powder, A80 cement, tripoly phosphate sodium STPP are carried out pre-mixing at mixing machine, make the premix powder; When making furnace roller, in vertical mixer, add electrofused mullite particle, flint clay particle, mullite powder, trichroite, premix powder, add explosion-proof fiber and Stainless Steel Fibre then equably while mixing, after mixing, add water gradually, form the mould material of good fluidity.This kind mould material is added in the furnace roller mould, adopt the vibration process for forming moulding, the demoulding after 3 days, the furnace roller after the demoulding dried 1 month at 25 ~ 40 ℃, got final product.
Prescription 1: the electrofused mullite particle 40kg of granularity≤3mm, 200 order mullite powder 14kg, the trichroite 25kg of granularity≤5mm, 180 order aquamaine stone flour 7kg, ultrafine silica powder 2.5kg, alumina powder 6kg, A80 cement 4kg, explosion-proof fiber 0.10kg, tripoly phosphate sodium STPP 0.2kg, Stainless Steel Fibre 2kg adds water 9.3kg.
Prescription 2: the electrofused mullite particle 25kg of granularity≤3mm, the flint clay particle 26kg of granularity 1-5mm, 200 order mullite powder 16kg, the trichroite 10kg of granularity≤5mm, 180 order aquamaine stone flour 8kg, ultrafine silica powder 2.5kg, alumina powder 6kg, A80 cement 4kg, explosion-proof fiber 0.12kg, tripoly phosphate sodium STPP 0.2kg, Stainless Steel Fibre 2kg adds water 8.8kg.
Prescription 3: the electrofused mullite particle 20kg of granularity≤3mm, the flint clay particle 22kg of granularity 1-5mm, 200 order mullite powder 20kg, the trichroite 15kg of granularity≤5mm, 180 order aquamaine stone flour 8kg, ultrafine silica powder 2.5kg, alumina powder 6kg, A80 cement 4kg, explosion-proof fiber 0.10kg, tripoly phosphate sodium STPP 0.2kg, Stainless Steel Fibre 2kg adds water 9.8kg.
With the prescription 1 stove illuminate of producing be embodiment 1, to produce De Lu Kun be embodiment 2 to prescription 2, prescription, the 3 stove illuminates of producing are embodiment 3.
The detection index is as follows:
The close full name of body is a volume density, for the quality of the drying material that has pore and the ratio of its cumulative volume, uses g/cm
3Expression.The method of inspection is seen the standard YB/T5200-93 of Ministry of Metallurgical Industry.
It is that the volume that has all open pores in the material of pore is planted with the ratio of its cumulative volume that void content typically refers to apparent porosity, represents with %.The method of inspection is seen the standard YB/T5200-93 of Ministry of Metallurgical Industry.
Compressive strength typically refers to cold crushing strength, at room temperature, and sample the be under pressure effect of load and ultimate stress when destroying.Represent with MPa.The method of inspection is seen the standard YB/T5201-93 of Ministry of Metallurgical Industry.
Folding strength typically refers to strength at normal temperature, and at room temperature, sample is subjected to the effect of bending load and ultimate stress when rupturing.Represent with MPa.The method of inspection is seen the standard YB/T5201-93 of Ministry of Metallurgical Industry.
1200 degree burn back line variation and are meant that sample is heated to 1200 spends, and is incubated 3 hours, the amount of its length irreversible change.Burn the percentage of front and back, back length variations represents with sample.The method of inspection is seen the standard YB/T5203-93 of Ministry of Metallurgical Industry.
The soft full name of lotus is a refractoriness under load, for refractory materials to high temperature and the coefficient resistivity of loading.Unit is degree centigrade that the method for inspection is with reference to the standard YB/T4024-91 of Ministry of Metallurgical Industry.
Table 1:
Numbering |
Body is close |
Void content |
Folding strength |
Compressive strength |
Line changes after 1200 ℃ of burnings |
Lotus is soft |
Embodiment 1 |
2.28 |
23.50 |
7.02 |
69.31 |
-0.12 |
1434 |
Embodiment 2 |
2.35 |
21.2 |
7.15 |
73.52 |
-0.14 |
1440 |
Embodiment 3 |
2.13 |
28.4 |
6.85 |
62.14 |
-0.11 |
1436 |
Embodiment 1,2,3 does not all burst for cold 42 times through 1100 ℃-shrend.