CN103360094B - Fireproof oxygen blowing tube coating - Google Patents

Abstract

The invention relates to the field of refractory materials for the steel metallurgy, and concretely relates to a fireproof oxygen blowing tube coating. The raw materials of the fireproof oxygen blowing tube coating comprise 20-50wt% of mullite, 8-15wt% of silicon carbide, 10-20wt% of andalusite, 5-10wt% of rho-alumina micropowder, 2-6wt% of aluminate cement, 5-10wt% of water glass and 2.1-6.5wt% of an additive. The coating has the characteristics of one-time forming through smearing, no need of baking, and obvious cost advantage. The coating can effectively solve the problems of cracks and expansion at a high temperature, and substantially improves the use quality; no damage of an oxygen blowing tube is powerfully guaranteed in the transportation and use processes by adopting a high-strength wear resistant material; and the coating has the advantages of extremely strong plasticity and adhesiveness, direct construction without any treatment of the oxygen blowing tube, simplicity and convenience.

Description

A kind of fireproof oxygen lance coating

Technical field

The present invention relates to ferrous metallurgy fire resisting material field, particularly, the present invention relates to a kind of fireproof oxygen lance coating.

Background technology

Oxygen lance is widely used in that steelmaking oxygen blowing prepurging, steel teeming ladle oxygen blast are opened and watered, the fields such as iron notch are opened in iron-smelting blast furnace oxygen blast, for extending the life-span of oxygen lance, international and domestic common practice is that the appearance of common oxygen blow steel pipe is coated to refractory substance, reaches the object that reduces labour intensity and reduce loss per ton steel.But most silicate or the magnesium oxide class materials of adopting of this coating, can play a role with the oxygen lance after these material coatings, but the problem of ubiquity three aspects:: after first moulding, all need low-temperature bake, both cost was high, extended again fabrication cycle; It two is that the thermal expansivity of coating under high temperature is not mated with metal, and intensity and wear resistance are inadequate, cause work-ing life short; It three is that oxygen lance all needs the processing such as rust cleaning before coating, wastes time and energy.

Summary of the invention

The object of the invention is to: provide a kind of for smearing the refractory materials formula of oxygen lance, once shaped, without baking, and formula by adjust the coefficient of expansion can be effectively and the metal material coefficient of expansion match, reach not explosion in use procedure, falling-off effect not, high strength and wear resistance, solve in-problem object in production, use procedure to reach.

Fireproof oxygen lance coating of the present invention, raw materials by weight comprises:

Mullite 20%-50%, silicon carbide 8%-15%, andaluzite 10%-20%, ρ-alumina powder 5%-10%, aluminate cement 2%-6%, water glass 5%-10%, additive 2.1%-6.5%.

According to fireproof oxygen lance coating of the present invention, described additive comprises the combination of the softening agent of 2%-6% and the detonation suppressor of 0.1%-0.5%.

Preferably, above-mentioned softening agent is Walocel MT 20.000PV or clay, and above-mentioned detonation suppressor is explosion-proof fiber or metallic aluminium.

According to fireproof oxygen lance coating of the present invention, wherein, according to the construction temperature difference in (four seasons), adjust initial set, final setting time, generally, the presetting period is about 1 hour, and it is optimum regime that final setting time is about 5 hours.For example: north of china in winter temperature low (subzero below 10 DEG C), the setting rate of cement, water glass is relatively slow, if coating can not reach some strength for a long time, will cause be full of cracks, so in the winter time in the situation of construction, one method needs baking, and another kind of method also can be added the setting accelerator of Sodium Silicofluoride as water glass, accelerates the setting rate of coating.According to the difference of temperature, Sodium Silicofluoride add-on is the 10%-30% of water glass consumption, and according to fireproof oxygen lance formulation for coating material of the present invention, Sodium Silicofluoride addition is 0.5%-3% by weight percentage.

The method of fireproof oxygen lance coating in preparation of the present invention, comprises the following steps:

1) mullite, silicon carbide, andaluzite, alumina powder and aluminate cement are put into stirrer and be dry mixed the glass of falling back, additive and water;

2) by step 1) gained mixture through stirring, obtain fireproof oxygen lance coating.

Particularly, further preferably prepare the method for upper fireproof oxygen lance coating, comprise the following steps:

1) mullite, silicon carbide, andaluzite, alumina powder and aluminate cement are put into stirrer and be dry mixed after 5 minutes, pour the water of water glass, additive and 4%-7% into;

2) by step 1) gained mixture through stirring after 7-10 minute, become sticky shape to make fireproof oxygen lance coating.

The above-mentioned fireproof oxygen lance coating making (can be about 60 minutes the engineering time), smears evenly (the about 3-5mm of thickness) on oxygen lance surface, after moulding, at room temperature maintenance gets final product bundling, packaging or use for 3 days.

Fireproof oxygen lance coating of the present invention, refractoriness is greater than 1750 DEG C, cohesive strength is greater than 0.65MPa, thermal conductivity is about 0.96W/mK, thermal shock resistance is greater than 60 times, folding strength (110 DEG C × 24h): 7.8MPa, ultimate compression strength (110 DEG C × 24h): 47MPa, its performance index are all better than product of the same type.

The present invention has the following advantages compared with the existing oxygen lance coating in this area:

1, the present invention smears once shaped, and maintenance is directly on-the-spot use after 3 days, and without baking, cost advantage is obvious.

2, coefficient of expansion mismatch problem in focusing between metal and refractory materials in formulating of recipe, the present invention effectively solves the problem that under high temperature, crackle produces, expands, and greatly improves functional quality.

3, because general oxygen lance is long, in transport, on-the-spot use procedure, pull, cause the damaged certain proportion that occupies, the present invention adopts high-strength wearable material, and strong guarantee oxygen lance is not damaged in transport, use procedure.

4, oxygen lance is through depositing; epidermis all can produce rusty stain or have greasy dirt, and common coating all needs after rusty stain or oil removal, just to smear, and oxygen lance refractory paint plasticity-of the present invention, adhesivity are extremely strong; to oxygen lance, it goes without doing that any processing can be constructed, simple and convenient.

Embodiment

Embodiment 1

Prepare fireproof oxygen lance coating, raw materials by weight comprises:

Mullite 45kg, silicon carbide 12kg, andaluzite 20kg, ρ-alumina powder 7kg, aluminate cement 4kg, water glass 10kg, carboxymethyl cellulose 2.5kg, metallic aluminium 0.3kg, water 5.6kg.

Prepare fireproof oxygen lance coating, comprise following methods:

After mullite, silicon carbide, andaluzite, ρ-alumina powder, aluminate cement are weighed up, put into stirrer and be dry mixed 5 minutes glass of falling back, carboxymethyl cellulose, metallic aluminium and water.Within 7-10 minute, become after sticky shape wait stirring, make fireproof oxygen lance coating, generally need to adjust the presetting period (being about 60 minutes).

Use above-mentioned fireproof oxygen lance coating, smear on oxygen lance surface evenly (3-5mm), at room temperature maintenance 3 days after moulding, packaging bundling can use.

Embodiment 2

Prepare fireproof oxygen lance coating, raw materials by weight comprises:

Mullite 20kg, silicon carbide 8kg, andaluzite 10kg, ρ-alumina powder 5kg, aluminate cement 3kg, water glass 5kg, Walocel MT 20.000PV 1.1kg, explosion-proof fiber 0.1kg, water 3kg, Sodium Silicofluoride 1kg.

Prepare fireproof oxygen lance coating, comprise following methods:

After mullite, silicon carbide, andaluzite, ρ-alumina powder, aluminate cement are weighed up, put into stirrer and be dry mixed 5 minutes glass of falling back, carboxymethyl cellulose, explosion-proof fiber, Sodium Silicofluoride and water.Within 7-10 minute, become after sticky shape wait stirring, make fireproof oxygen lance coating.Generally need to adjust the presetting period (being about 60 minutes).

Embodiment 3

Prepare fireproof oxygen lance coating, raw materials by weight comprises:

Mullite 35kg, silicon carbide 10kg, andaluzite 15kg, ρ-alumina powder 7kg, aluminate cement 5kg, water glass 7kg, Guangxi clay 4kg, explosion-proof fiber 0.2kg, water 4.7kg.

Prepare fireproof oxygen lance coating method with embodiment 1.

Embodiment 4

Prepare fireproof oxygen lance coating, raw materials by weight comprises:

Mullite 20kg, silicon carbide 8kg, andaluzite 10kg, ρ-alumina powder 5kg, aluminate cement 3kg, water glass 5kg, Guangxi clay 2.5kg, metallic aluminium 0.1kg, water 3kg, Sodium Silicofluoride 1.5kg.

Prepare fireproof oxygen lance coating, comprise following methods:

After mullite, silicon carbide, andaluzite, ρ-alumina powder, aluminate cement are weighed up, put into stirrer and be dry mixed 5 minutes glass of falling back, Guangxi clay, metallic aluminium, Sodium Silicofluoride and water.Within 7-10 minute, become after sticky shape wait stirring, make fireproof oxygen lance coating.Generally need to adjust the presetting period (being about 60 minutes).

Claims (3)

1. a fireproof oxygen lance coating, is characterized in that, described fireproof oxygen lance coating raw material comprises by weight percentage:

Mullite 20%-50%, silicon carbide 8%-15%, andaluzite 10%-20%, ρ-alumina powder 5%-10%, aluminate cement 2%-6%, water glass 5%-10%, additive 2.1%-6.5%;

Wherein, described additive comprises the combination of the softening agent of 2%-6% and the detonation suppressor of 0.1%-0.5%; Described softening agent is Walocel MT 20.000PV or clay, and described detonation suppressor is metallic aluminium.

2. fireproof oxygen lance coating according to claim 1, is characterized in that, also comprises Sodium Silicofluoride 0.5-3%.

3. a method of preparing fireproof oxygen lance coating described in claim 1, comprises the following steps:

1) mullite, silicon carbide, andaluzite, alumina powder and aluminate cement are put into stirrer and be dry mixed the glass of falling back, additive and water;

2) by step 1) gained mixture is through stirring, and obtains fireproof oxygen lance coating.