CN104762559B - Method for producing steel plate for hydrogen-contacting equipment - Google Patents

Abstract

The invention discloses a method for producing a steel plate for hydrogen-contacting equipment. The process route adopted by the method includes smelting in a rotating furnace, LF refining, VD vacuum refining, continuous casting, plate blank heating, controlled rolling, direct quenching and heat treatment, and steel comprises, by mass, 0.10%-0.15% of C, 0.10% or less of Si, 0.30%-0.60% of Mn, 0.010% or less of P, 0.005% or less of S, 0.020%-0.050% of Alt, 2.0%-2.5% of Cr, 0.95%-1.10% of Mo, 0.01%-0.02% of Ti, 0.010% or less of Sn, 0.012% or less of P and Sn, and the balance Fe and residual elements. The method is used for producing 12Cr2Mo1R steel plates having the thicknesses ranging from 16mm to 100mm and guaranteeing flaw detection and mechanical property, and the actual mass and all properties of obtained products are excellent; after maximum simulation postweld heat treatment is conducted on the steel plate, the yield strength allowance of the steel plate ranges from 70 Mpa to 90 Mpa, the tensile strength allowance of the steel plate ranges from 35 Mpa to 60 Mpa, the impact performance at the low temperature of minus 30 DEG C is stable, and the allowance is large.

Description

A kind of production method of hydrogen-contacting equipment steel plate

Technical field

The invention belongs to smelting iron and steel and rolling technique are and in particular to arrive a kind of production method of hydrogen-contacting equipment steel plate.

Technical background

Face hydrogen steel mainly for the manufacture of in high temperature (250 DEG C of temperature ＞), high pressure (hydrogen dividing potential drop ＞ 1.4mpa), face under hydrogen environment The pressure vessel and equipment using, is widely used in the relevant industries such as petrochemical industry, Coal Chemical Industry, electric power.Wherein the overwhelming majority is used for making Make the hydrogenation plant in oil refining and chemical industry, also fraction is defeated for facing the separation under hydrogen environment, heat transmission equipment and pressure Give line equipment to manufacture etc..

What China used at present faces hydrogen 12cr2mo1r steel plate in addition to the requirement that need meet gb713-2014, also needs to ensure steel Mechanical property after Simulated post-weld heat treatment for the plate meets standard and requires, and p- 30 DEG C of low temperature impact properties, field trash, harmful Element, gas content etc. propose higher requirement.

Controlled rolling (controlled rolling) is by METAL HEATING PROCESS system, deformation system in the operation of rolling With the reasonable control of temperature schedule, so that pyroplastic deformation is combined with solid-state phase changes, to obtain tiny grain structure, so that steel is had There is the rolling new technology of excellent comprehensive mechanical property.It can improve steel tissue crystal grain, and the intensity and the low temperature that improve steel plate are tough Degree, simultaneously can be with energy saving, Simplified flowsheet it is also possible to give full play to alloys producing.Direct quenching is to utilize crmo Steel roll rear waste heat steel from deformed austeaite be cooled to below bainite transformation temperature and finally give bainite heat at Science and engineering skill.Because the abundant dissolving of alloying element during controlled rolling increased the quenching degree of austenite, be conducive to subsequent Direct quenching；In addition controlled rolling has refined austenite crystal, increased austenite deformation band, provides forming core for follow-up phase transformation Point, is expected to obtain preferable tissue morphology, thus obtaining excellent intensity and toughness combination after tempering.

Content of the invention

The purpose of the present invention in a kind of production method of hydrogen-contacting equipment steel plate, using controlled rolling+direct quenching+tempering The method combining produces 16 ~ 100mm guaranteed cost, protects the hydrogen-contacting equipment steel plate 12cr2mo1r steel of flaw detection.Steel plate is through maximum norm Intend post weld heat treatment, in 70～90mpa, tensile strength surplus capacity is in 35～60mpa, -30 DEG C of low temperature for its yield strength surplus capacity Impact property is stable, surplus is big.

The technical scheme of invention:

A kind of production method of hydrogen-contacting equipment steel plate, is converter smelting → lf refine → vd vacuum fine using process route Refining → continuous casting → heating of plate blank → controlled rolling → direct quenching → heat treatment.The chemical composition mass percent (wt.%) of steel As follows: c=0.10～0.15, si≤0.10, mn=0.30～0.60, p≤0.010, s≤0.005, alt=0.020～0.050, Cr=2.0～2.5, mo=0.95～1.10, ti=0.01 ~ 0.02, sn≤0.010, p+sn≤0.012；Remaining is fe and residual unit Element.

Comprise the technical steps that:

A. converter smelting: guarantee c >=0.05% of tapping, p≤0.006%, tapping temperature >=1580 DEG C；Avoid tapping process Slag；

B. lf refine: guarantee that the white slag retention time controls in more than 20min；Carry out secondary de- p before lf stove outbound, control p≤0.004%；

C. vd vacuum refining: the guarantor's vacuum time >=23min under≤67pa；Vd carries out Calcium treatment after breaking sky；

D. continuous casting: it is 260mm or 300mm that continuous casting adopts section, and continuous casting carries out whole process protection casting, and pouring temperature presses liquid Liquidus temperature+(45～55 DEG C) controls；

E. heating of plate blank: slab cold 12 ~ 16 hours temperature of offline rear heap send shove charge；Slab is heated in walking-beam furnace, temperature Degree controls at 1100 ~ 1250 DEG C；

F. controlled rolling: rolled using cr mode, 1000～1150 DEG C of start rolling temperature；One stage finishing temperature ＞ 950 DEG C it is ensured that rear three percentage pass reductions are more than 15%；At 880 ~ 910 DEG C, finish rolling adds up reduction ratio ＞ 48% to two-stage start rolling temperature, Finishing temperature >=850 DEG C；

G. direct quenching: enter coolant-temperature gage >=850 DEG C, 200 DEG C of red temperature ＜, cooling rate controls in 3～8 DEG C/s；

H. heat treatment: adopt tempering process, 700 ~ 730 DEG C of temperature, temperature retention time 3.5 ~ 6min/mm.

Inventive principle and chemical element consumption control mechanism:

C: carbon, in steel alloy, often forms carbide with other alloying elements, can rise under room temperature or lower temperature To invigoration effect, but at high temperature, some carbides easily decompose, and produce harmful effect to creep resistance and creep rupture strength.Special It is not the generation that can aggravate hydrogen attack under facing hydrogen service condition.

Si: helpful to the intensity improving steel, but easily promote temper embrittlement, content is preferably as far as possible low.

Mn: it is solution strengthening element, all favourable to the intensity and toughness improving steel plate, but easily promote temper embrittlement, protecting In the case of card hardness of steel, content is preferably low.

P: for suppression temper embrittlement sensitivity and the cold short tendency of reduction, content should be as far as possible low.

S: the raising of unfavorable upper mounting plate energy and toughness, and have hot cracking tendency, content should be as far as possible low.

Sn: one of important impurity element of impact temper brittleness, should strictly control, content should be as far as possible low.

The present invention passes through to ensure compression ratio from big cross section continuous casting billet, and composition strictly controls containing of each harmful element Amount, ensures the cleanliness factor of steel by lf+vd technique；The grain size of steel is made to reach using controlled rolling+direct quenching+temper 7.5～9.0 grades.By effective enforcement of above-mentioned measure, it has been successfully produced out 16mm～100mm and has protected flaw detection, protect mechanical property Hydrogen-contacting equipment 12cr2mo1r steel plate.The present invention passes through from converter smelting to the whole process of steel plate heat treatment strictly by upper State production technology execution, the quality in kind properties obtaining product are excellent: through maximum analog post weld heat treatment, it surrenders steel plate In 70～90mpa, in 35～60mpa, -30 DEG C of low temperature impact properties are stable, surplus for tensile strength surplus capacity for Strength surplus amount Greatly.

Specific embodiment

With reference to embodiment, the present invention will be further described.

Embodiment 1 ~ 4, thickness is that 16mm～100mm protects flaw detection, protects mechanical property hydrogen-contacting equipment 12cr2mo1r steel plate, It is converter smelting → lf refine → vd vacuum refining → continuous casting → heating of plate blank → controlled rolling → directly quench using process route Fire → heat treatment.The chemical composition mass percent (wt%) of steel is as follows: c=0.10～0.15, si≤0.10, and mn=0.30～ 0.60, p≤0.010, s≤0.005, alt=0.020～0.050, cr=2.0～2.5, mo=0.95～1.10, ti=0.01 ~ 0.02, sn≤0.010, p+sn≤0.012；Remaining is fe and relict element.

Comprise the technical steps that:

A. converter smelting: guarantee c >=0.05% of tapping, p≤0.006%, tapping temperature >=1580 DEG C；Avoid tapping process Slag；

B. lf refine: guarantee that the white slag retention time controls in more than 20min；Carry out secondary de- p before lf stove outbound, control p≤0.004%；

C. vd vacuum refining: the guarantor's vacuum time >=23min under≤67pa；Vd carries out Calcium treatment after breaking sky；

D. continuous casting: it is 260mm or 300mm that continuous casting adopts section, and continuous casting carries out whole process protection casting, and pouring temperature presses liquid Liquidus temperature+(45～55 DEG C) controls；

E. heating of plate blank: slab cold 12 ~ 16 hours temperature of offline rear heap send shove charge；Slab is heated in walking-beam furnace, temperature Degree controls at 1100 ~ 1250 DEG C；

F. controlled rolling: rolled using cr mode, 1000～1150 DEG C of start rolling temperature；One stage finishing temperature ＞ 950 DEG C it is ensured that rear three percentage pass reductions are more than 15%；At 880 ~ 910 DEG C, finish rolling adds up reduction ratio ＞ 48% to two-stage start rolling temperature, Finishing temperature >=850 DEG C；

G. direct quenching: enter coolant-temperature gage >=850 DEG C, 200 DEG C of red temperature ＜, cooling rate controls in 3～8 DEG C/s；

H. heat treatment: adopt tempering process, 700 ~ 730 DEG C of temperature, temperature retention time 3.5 ~ 6min/mm.

According to four embodiment 12cr2mo1r finished steels of said method test, chemical composition such as table 1；Mechanical property is examined Survey result such as table 2, in table, t is steel plate thickness.

Table 1 embodiment chemical composition (wt.%)

Table 2 embodiment mechanics properties testing result

Product surface quality is excellent, outer inspection qualification rate 100%, i level flaw detection qualification rate 100%, properties percent of pass 100%, steel plate Sample through maximum analog post weld heat treatment, at 1/2 thickness of slab, in more than 100mpa, have more than needed yield strength surplus capacity by tensile strength end to end Amount has fully met the technical requirements that 12cr2mo1r faces hydrogen steel in 35～60mpa, -30 DEG C of impacts substantially in more than 250j.

Claims (1)

1. a kind of production method of hydrogen-contacting equipment steel plate, is converter smelting → lf refine → vd vacuum refining using process route → continuous casting → heating of plate blank → controlled rolling → direct quenching → heat treatment it is characterised in that: the chemical composition percent mass of steel Than for c=0.10～0.15, si≤0.10, mn=0.30～0.60, p≤0.010, s≤0.005, alt=0.020～0.050, cr =2.0～2.5, mo=0.95～1.10, ti=0.01 ~ 0.02, sn≤0.010, p+sn≤0.012, remaining is fe and residual unit Element；

Comprise the technical steps that:

A. converter smelting: guarantee c >=0.05% of tapping, p≤0.006%, tapping temperature >=1580 DEG C, it is to avoid tapping process slag ；

B. lf refine: guarantee that the white slag retention time controls in more than 20min, before lf stove outbound, carry out secondary de- p, control p≤ 0.004%；

C. vd vacuum refining: the guarantor's vacuum time >=23min under≤67pa；Vd carries out Calcium treatment after breaking sky；

D. continuous casting: it is 260mm or 300mm that continuous casting adopts section, and continuous casting carries out whole process protection casting, and pouring temperature presses liquidus curve Temperature+(45～55 DEG C) controls；

E. heating of plate blank: slab cold 12 ~ 16 hours temperature of offline rear heap send shove charge, and slab is heated in walking-beam furnace, temperature control System is at 1100 ~ 1250 DEG C；

F. controlled rolling: rolled using cr mode, 1000～1150 DEG C of start rolling temperature, 950 DEG C of stage finishing temperature ＞, protect After card, more than 15%, at 880 ~ 910 DEG C, finish rolling adds up reduction ratio ＞ 48%, finish to gauge to two-stage start rolling temperature to three percentage pass reductions Temperature >=850 DEG C；

G. direct quenching: enter coolant-temperature gage >=850 DEG C, 200 DEG C of red temperature ＜, cooling rate controls in 3～8 DEG C/s；

H. heat treatment: adopt tempering process, 700 ~ 730 DEG C of temperature, temperature retention time 3.5 ~ 6min/mm.