CN103031496B

CN103031496B - Cast steel roller and fabrication technology thereof

Info

Publication number: CN103031496B
Application number: CN201310000392.7A
Authority: CN
Inventors: 江沛琪
Original assignee: 江苏钢宝轧辊有限公司
Priority date: 2013-01-22
Filing date: 2013-01-22
Publication date: 2014-12-03
Also published as: CN103031496A

Abstract

The invention discloses a cast steel roller which comprises an alloy outer layer and a core part, wherein the alloy outer layer comprises the following chemical components by weight percentage: 1.50-2.20% of C, less than or equal to 0.060% of Si, 0.40-1.20% of Mn, less than or equal to 0.030% of P, less than or equal to 0.025% of S, 3.00-8.00% of Cr, 0.00-1.50% of Ni, 2.00-8.00% of Mo, 2.00-9.00% of V, 0.00-3.00% of W, 0.00-0.85% of Nb, 0.00-1.20% of Al, and the balance of Fe, and the core part comprises the following chemical components by weight percentage: 2.8-3.4% of C, 1.8-2.6% of Si, 0.3-0.6% of Mn, less than or equal to 0.08% of P, less than or equal to 0.03% of S, and 0.04-0.06% of Mg. The cast steel roller adopts the alloy outer layer and the core part comprising the above components, is good in wear resistance and obdurability, high in accident resistance, and long in service life, and can avoid rolling accidents; the alloy outer layer and the core part can be sufficiently bonded metallurgically; the use amount of elements with higher adverse effects in use is decreased; the production cost is lowered; and using conditions are improved.

Description

A kind of cast steel roll and preparation technology thereof

Technical field

The invention belongs to Steel Rolling roll technology field, be specifically related to a kind of cast steel roll and preparation technology thereof.

Background technology

Along with developing rapidly of Iron And Steel Industry, the production capacity of the current hot rolled strip mill of China has reached more than 300,000,000 ton, roll is a large amount of vitals that consume during steel rolling is produced, therefore the quality of roll quality not only affects the surface quality of stocking, but also affect the operating rate of milling train, directly restricting the economic benefit of enterprise.At present state-of-the-art on roll material is high-speed steel roll, and itself and conventional rapid steel class formula are different, and it exists following shortcoming:

1. working conditions is harsher, and roller temperature control slightly mistake will be peeled off even explosion, causes rolling accident, and user is had to inconvenience more;

2. manufacturing process elaborate, product rejection rate is high, and breaker roll manufacturer cost pressure is too large;

3. the high and practical steel transportation amount of cost is not significantly improved, and to using and all bad acceptance of supplier, the quality objection of generation and commercial dispute are also many.

4. consumables cost is higher, consumes alloy resource too much.

Summary of the invention

Technical problem to be solved by this invention is for above-mentioned the deficiencies in the prior art, a kind of cast steel roll and preparation technology thereof are provided, make roll meet Composition Design rationally, casting and thermal treatment process maturation, the requirement such as production cost is lower, product rejection rate is low and anti-accident ability is strong.

The technical solution adopted in the present invention is: a kind of cast steel roll, comprise alloy outer and core, and the chemical component weight percentage ratio of described alloy outer is: C 1.50-2.20%, Si≤0.060%, Mn 0.40-1.20%, P≤0.030%, S≤0.025%, Cr 3.00-8.00%, Ni 0.00-1.50%, Mo 2.00-8.00%, V 2.00-9.00%, W 0.00-3.00%, Nb 0.00-0.85%, Al 0.00-1.20%, surplus is Fe;

The chemical component weight percentage ratio of described core is: C 2.8-3.4%, Si 1.8-2.6%, Mn 0.3-0.6%, P≤0.08%, S≤0.03%, Mg 0.04-0.06%.

As preferably, adopt centrifugal casting technique by integral two kinds of different metallic substance consolutes, first alloy skin, core composition carries out accurate combo and carries out respectively intermediate frequency furnace melting, work as alloy outer, the concrete composition of core is in the time of stokehold spectral detection and the specific requirement of accurate adjustment conformance with standard technique, by alloy outer, core is distinguished refining, , when reaching when setting requires, alloy outer melting taps, increase foreign material simultaneously, refining slag filtration treatment operation, the molten steel of tapping is poured in the whizzer casting mold of high speed rotating, the pouring temperature of alloy outer molten steel is 1430-1460 DEG C, when lower machine horse back after alloy outer molten steel solidification carry out vertical group of case, to rinsing cast core molten iron in it, the pouring temperature of core molten iron is 1410-1450 DEG C, thereby make the complete metallurgical melting of alloy outer and core, junction does not have carbon segregation and shrinkage defect substantially.

As preferably, described foreign material filtration treatment operation refers to and in the time that slagging-off is tapped a blast furnace, adopts the heat-resistance stainless steel silk screen of restriction order number to carry out filtration treatment to iron liquid, filters impurity and ensure the molten quality of inside and outside two-layer metallurgical junction syzygies with refining slag.

As preferably, first test and roughing for the blank roll after cooling forming, after completing, anneal, quenching and tempering heat treatment: annealing is that roll is heated to 900-980 DEG C, then carry out stove cold; Quenching be with the heat-up rate of≤30 DEG C/h be warmed up to >=600 DEG C after, again heat-up rate is promoted to≤40 DEG C/h, roll is heated to 950-1100 DEG C, and by the insulation of insulation specified time, and then make roll cooling fast by mode air-cooled or spraying, when be cooled to 350～300 DEG C to carry out temper later; Tempering temperature is 500-680 DEG C, and times of tempering is at least three times, make alloy outer hardness reach 80HSD more than, paralympic obtaining melts fully and changes.

Beneficial effect of the present invention is: the present invention adopts alloy outer and the core of mentioned component, its wear resistance and good toughness, anti-accident ability are strong, long service life, avoid rolling accident, complete metallurgical binding between alloy outer and core, reduced the element proportional quantity that disadvantageous effect is larger in practicality simultaneously, reduce production cost, improved working conditions simultaneously; Casting of the present invention and thermal treatment process, utilize material " secondary hardening characteristic " to ensure rolling use properties, and reduce the meticulous and complexity of production technique, reduces condemnation factor.

Brief description of the drawings

Fig. 1 is technical process for casting figure of the present invention;

Fig. 2 is heat treatment cycle curve figure of the present invention.

Embodiment

Below in conjunction with the accompanying drawings and the specific embodiments the present invention is described in further detail.

Embodiment mono-: a kind of cast steel roll, comprise alloy outer and core, the chemical component weight percentage ratio of described alloy outer is: C 1.50-2.20%, Si≤0.060%, Mn 0.40-1.20%, P≤0.030%, S≤0.025%, Cr 3.00-8.00%, Ni 0.00-1.50%, Mo 2.00-8.00%, V 2.00-9.00%, W 0.00-3.00%, Nb 0.00-0.85%, Al 0.00-1.20%, surplus is Fe;

Key of the present invention is to have reduced the proportional quantity of the element that disadvantageous effect is larger in practicality, proportional quantity by Si is reduced to :≤0.060%, the proportional quantity of W is reduced to: 0.00-3.00%, the proportional quantity of Nb is reduced to: 0.00-0.85%, the proportional quantity of Al is reduced to: 0.00-1.20%, the roll of the present embodiment is reduced costs and improve working conditions, performance and rapid steel are same or similar simultaneously, ensure its purposes and effect.

The preparation technology of cast steel roll of the present invention is: as shown in Figure 1, adopt centrifugal casting technique by integral two kinds of different metallic substance consolutes, first alloy skin, core composition carries out accurate combo and carries out respectively intermediate frequency furnace melting, work as alloy outer, the concrete composition of core is in the time of stokehold spectral detection and the specific requirement of accurate adjustment conformance with standard technique, by alloy outer, core is distinguished refining, , when reaching when setting requires, alloy outer melting taps, increase foreign material simultaneously, refining slag filtration treatment operation, the molten steel of tapping is poured in the whizzer casting mold of high speed rotating, the pouring temperature of alloy outer molten steel is 1430-1460 DEG C, when lower machine horse back after alloy outer molten steel solidification carry out vertical group of case, to rinsing cast core molten iron in it, the pouring temperature of core molten iron is 1410-1450 DEG C, thereby make the abundant metallurgical melting of alloy outer and core, junction does not have carbon segregation and shrinkage defect substantially.Increase foreign material filtration treatment operation and refer to and in the time that slagging-off is tapped a blast furnace, adopt the heat-resistance stainless steel silk screen of restriction order number to carry out filtration treatment to iron liquid, filter impurity and ensure the molten quality of inside and outside two-layer metallurgical junction syzygies with refining slag.

As shown in Figure 2, first test and roughing for the blank roll after cooling forming, after completing, anneal, quenching and tempering heat treatment, thermal treatment process is round-the-clock to be checked every 30 minutes, heating, soaking time and temperature are finely tuned according to product specification and user's operating mode: annealing is that roll is heated to 900-980 DEG C, then carry out stove cold; Quenching be with the heat-up rate of≤30 DEG C/h be warmed up to >=600 DEG C after, again heat-up rate is promoted to≤40 DEG C/h, roll is heated to 950-1100 DEG C, and by the insulation of insulation specified time, then make roll cooling fast by mode air-cooled or spraying, when being cooled to carry out temper after 300-350 DEG C; Tempering temperature is 500-680 DEG C, times of tempering is revised according to hardness that product requires and paralympic amount detection controlling valu (ferrite detector), it is at least three times, make alloy outer hardness reach 80HSD more than, paralympic obtaining melts fully and changes.

The present invention adopts alloy outer and the core of mentioned component, its wear resistance and good toughness, anti-accident ability are strong, long service life, avoid rolling accident, complete metallurgical binding between alloy outer and core, reduced the element proportional quantity that disadvantageous effect is larger in practicality simultaneously, reduce production cost, improved working conditions simultaneously; Casting of the present invention and thermal treatment process, utilize material " secondary hardening characteristic " to ensure rolling use properties, and reduce the meticulous and complexity of production technique, reduces degree of scrapping.

The present invention transforms equipment for Heating Processing simultaneously, and its content comprises:

1, increase blowing/spraying machine;

2, change into Sweet natural gas by electric energy;

3, change preventing deformation base plate;

4, heat treated article bearing changes heat resisting iron material.

Utilize the cast steel roll of formula of the present invention and preparation technology's exploitation also to there is following beneficial effect:

1. properties is except red hardness is slightly on the low side, and other index is all higher than former rapid steel series products, and overall steel transportation amount improves approximately 13.3%;

2. material newly developed is approximately lower by 32.4% than former rapid steel material material cost, and alloy resource consumes less, meets national resources conservation policy;

3. the product process-cycle falls 8.7% than rapid steel product, and output is than former rapid steel product high approximately 5.6%;

4. the principle that cost is low, performance meets well market " inexpensive ", supply falls short of demand for current Europe user.

The above, be only preferred embodiment of the present invention, therefore can not limit scope of the invention process with this, the equivalence of doing according to the present patent application the scope of the claims and description changes and modifies, and all should still remain within the scope of the patent.

Claims

1. a cast steel roll, comprises alloy outer and core, it is characterized in that: the chemical component weight percentage ratio of described alloy outer is: C 1.50-2.20%, Si≤0.060%, Mn 0.40-1.20%, P≤0.030%, S≤0.025%, Cr 3.00-8.00%, Ni 0.00-1.50%, Mo 2.00-8.00%, V 2.00-9.00%, W 0.00-3.00%, Nb 0.00-0.85%, Al 0.00-1.20%, surplus is Fe;

The chemical component weight percentage ratio of described core is: C 2.8-3.4%, Si 1.8-2.6%, Mn 0.3-0.6%, P≤0.08%, S≤0.03%, Mg 0.04-0.06%;

The preparation technology of this cast steel roll is: adopt centrifugal casting technique by integral two kinds of different metallic substance consolutes, first alloy skin, core composition carries out accurate combo and carries out respectively intermediate frequency furnace melting, work as alloy outer, the concrete composition of core is in the time of stokehold spectral detection and the specific requirement of accurate adjustment conformance with standard technique, by alloy outer, core is distinguished refining, when reaching when setting requires, alloy outer melting taps, increase foreign material simultaneously, refining slag filtration treatment operation, the molten steel of tapping is poured in the whizzer casting mold of high speed rotating, the pouring temperature of alloy outer molten steel is 1430-1460 DEG C, when lower machine horse back after alloy outer molten steel solidification carry out vertical group of case, to rinsing cast core molten iron in it, the pouring temperature of core molten iron is 1410-1450 DEG C, thereby make the complete metallurgical melting of alloy outer and core, junction does not have carbon segregation and shrinkage defect substantially.

2. the preparation technology of a kind of cast steel roll according to claim 1, it is characterized in that: described foreign material filtration treatment operation refers to and in the time that slagging-off is tapped a blast furnace, adopts the heat-resistance stainless steel silk screen of restriction order number to carry out filtration treatment to iron liquid, filters impurity and ensure the molten quality of inside and outside two-layer metallurgical junction syzygies with refining slag.

3. the preparation technology of a kind of cast steel roll according to claim 1 and 2, it is characterized in that: first test and roughing for the blank roll after cooling forming, after completing, anneal, quenching and tempering heat treatment: annealing is that roll is heated to 900-980 DEG C, then carries out stove cold; Quenching be with the heat-up rate of≤30 DEG C/h be warmed up to >=600 DEG C after, again heat-up rate is promoted to≤40 DEG C/h, roll is heated to 950-1100 DEG C, and by the insulation of insulation specified time, and then make roll cooling fast by mode air-cooled or spraying, when be cooled to 350～300 DEG C to carry out temper later; Tempering temperature is 500-680 DEG C, and times of tempering is at least three times, makes more than the hardness of alloy outer reaches 80HSD, is paralympicly changed fully.