CN108330378A - A kind of production method of hydrogen-contacting equipment 14Cr1MoR steel - Google Patents

Abstract

A kind of hydrogen-contacting equipment 14Cr1MoR steel and its production method use process route for converter smelting → LF refining → VD vacuum refinings → continuous casting → heating of plate blank → controlled rolling → direct quenching → heat treatment.The chemical composition mass percent of steel is C=0.10~0.15, Si=0.50~0.60, Mn=0.40~0.60, P≤0.007, S≤0.005, Alt=0.020~0.050, Cr=1.20~1.50, Mo=0.50~0.65, Ti=0.01 ~ 0.02, Ni=0.10 ~ 0.15, Sn≤0.005, J coefficient=(Si+Mn) ×（P+Sn）×10⁴≤ 120, remaining is Fe and relict element.The present invention produces the 14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment that 20mm~100mm protects flaw detection, protects mechanical property, and the quality in kind properties for obtaining product are excellent：Control of deleterious element is stringent in steel plate ingredient, and the J controls of temper embrittlement coefficient are below 90.Steel plate is through maximum analog post weld heat treatment, and yield strength surplus capacity is in 100Mpa or more, and for tensile strength surplus capacity in 30~80Mpa, 18 DEG C of low temperature impact properties stabilizations, surplus are big.

Description

A kind of production method of hydrogen-contacting equipment 14Cr1MoR steel

Technical field

The invention belongs to smelting iron and steel, rolling and heat treatment technics, and in particular to a kind of hydrogen-contacting equipment 14Cr1MoR The production method of steel.

Technical background

14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment mainly for the manufacture of in high temperature, high pressure, face hydrogen environment under the pressure that uses hold Device equipment is widely used in the relevant industries such as petrochemical industry, coal chemical industry, electric power.

Face hydrogen 14Cr1MoR steel plates in addition to the requirement that need to meet GB/T 713-2014 what China used, also needs to ensure steel After Simulated post-weld heat treatment, the mechanical property at plate thickness 1/2 meets standard and requires plate, and p- 18 DEG C of low temperature impact properties, Field trash, harmful element, gas content etc. are put forward higher requirements.

Controlled rolling（Controlled rolling）It is during the rolling process by METAL HEATING PROCESS system, deformation system With the reasonable control of temperature schedule, pyroplastic deformation is made to be combined with solid-state phase changes, to obtain tiny grain structure, steel is made to have There is the rolling new process of excellent comprehensive mechanical property.It can improve steel tissue crystal grain, and intensity and the low temperature for improving steel plate are tough Degree, at the same can it is energy saving, simplify technique, alloys producing can also be given full play to.Direct quenching is to utilize Steel are cooled to bainite transformation temperature or less from deformed austeaite rapidly and finally obtained by the rear waste heat that rolls of 14Cr1MoR steel The burning optimization on line technique of bainite.Since the abundant dissolving of alloying element during controlled rolling increases the through hardening of austenite Property, be conducive to subsequent direct quenching；In addition controlled rolling has refined austenite grain, austenite deformation band is increased, after being Continuous phase transformation provides nucleation point, is expected to obtain ideal tissue morphology, to obtain excellent intensity and toughness combination after tempering.

Invention content

Method it is an object of the invention to be combined using controlled rolling+direct quenching+tempering produces 20mm ~ 100mm Guaranteed cost, a kind of 14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment for protecting flaw detection.Steel plate is through maximum analog post weld heat treatment, plate thickness 1/2 The yield strength surplus capacity at place is in 100Mpa or more, and for tensile strength surplus capacity in 30~80Mpa, -18 DEG C of low temperature impact properties are steady Calmly, surplus is big.

Technical scheme of the present invention：

A kind of production method of 14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment uses process route true for converter smelting → LF refining → VD Empty refining → continuous casting → heating of plate blank → controlled rolling → direct quenching → heat treatment.The chemical composition mass percent of steel be C= 0.10~0.15, Si=0.50~0.60, Mn=0.40~0.60, P≤0.007, S≤0.005, Alt=0.020~0.050, Cr= 1.20~1.50, Mo=0.50~0.65, Ti=0.01 ~ 0.02, Ni=0.10 ~ 0.15, Sn≤0.005, J coefficient=(Si+Mn) × （P+Sn）×10⁴≤120（Constituent content is substituted into percentage in formula）, remaining is Fe and relict element.

It comprises the technical steps that：

A. converter smelting：Tap C >=0.05%, P≤0.006%, tapping temperature >=1580 DEG C；Avoid tapping process slag；

B. LF refining：The white slag retention time controls in 20min or more；The secondary de- P of progress before LF stoves are outbound, control P≤ 0.004%；LF refining carries out Calcium treatment before terminating；

C. VD vacuum refinings：Guarantor's vacuum time >=20min at≤67Pa；

D. continuous casting：Continuous casting uses section for 260mm or 300mm, and continuous casting carries out whole process protection casting, and pouring temperature presses liquidus curve temperature Degree+(25~35 DEG C) controls；

E. heating of plate blank：Cold 16 ~ 20h the temperature of heap send shove charge, slab to be heated in stepping furnace after slab is offline, temperature control At 1180 ~ 1230 DEG C；

F. controlled rolling：It is rolled using CR modes, 1050~1150 DEG C of start rolling temperature；One 950 DEG C of stage finishing temperature ＞ is protected Three percentage pass reductions are 16% or more after card；For two-stage start rolling temperature at 880 ~ 910 DEG C, finish rolling adds up reduction ratio ＞ 48%, finish to gauge Temperature >=860 DEG C；

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

H. it is heat-treated：Using tempering process, 700 ~ 730 DEG C of temperature, 3 ~ 5min/mm of soaking time.

Inventive principle and chemical element dosage control mechanism：

C：Carbon often forms carbide in steel alloy with other alloying elements, can be played under room temperature or lower temperature strong Change acts on, but at high temperature, some carbide are easy to decompose, and harmful effect is generated to creep resistance and creep rupture strength.Especially In the case where facing hydrogen service condition, the generation of hydrogen attack can be aggravated.

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

Mn：It is solution strengthening element, it is advantageous to the intensity and toughness that improve steel plate, but easily promote temper embrittlement, it is protecting Content is preferably low in the case of demonstrate,proving hardness of steel.

P：To inhibit temper embrittlement sensibility and reducing cold short tendency, content should be low as possible.

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

Sn：One of the important impurity element for influencing temper brittleness, should strictly control, content should be low as possible.

Ni：It is pure solid solution element in steel, it is present in α and γ iron phases with iron in the form of dissolving each other, by it in crystal grain Interior interior suction-operated fining ferrite grains, improve the impact toughness of steel, while the quenching degree of steel also can be improved.

The present invention strictly controls containing for each harmful element by selecting big cross section continuous casting billet to ensure compression ratio on ingredient Amount, ensures the cleanliness factor of steel by LF+VD techniques；Steel is set to obtain using controlled rolling+direct quenching+tempering heat treatment ideal Organization type, and grain size reaches 7.5~9.0 grades.By effective implementation of above-mentioned measure, be successfully produced out 20mm~ The 14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment that 100mm protects flaw detection, protects mechanical property.The present invention by from converter smelting to from steel plate hot The whole process of reason is strictly pressed above-mentioned production technology and is executed, and the quality in kind properties for obtaining product are excellent：Steel plate delivery state And after maximum analog post weld heat treatment, for the yield strength surplus capacity at plate thickness 1/2 in 100Mpa or more, tensile strength is more than needed For amount in 30~80Mpa, -18 DEG C of low temperature impact properties stabilizations, surplus are big.

Specific implementation mode

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

Thickness is that 20mm~100mm protects flaw detection, protects mechanical property 14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment, using technique road Line is：At converter smelting → LF refining → VD vacuum refinings → continuous casting → heating of plate blank → controlled rolling → direct quenching → heat Reason.The chemical composition mass percent of steel is：C=0.10~0.15, Si=0.50~0.60, Mn=0.40~0.60, P≤ 0.007, S≤0.005, Alt=0.020~0.050, Cr=1.20~1.50, Mo=0.50~0.65, Ti=0.01 ~ 0.02, Ni= 0.10 ~ 0.15, Sn≤0.005, J coefficient=(Si+Mn) ×（P+Sn）×10⁴≤ 120 [constituent content is with percentage in formula（%）Generation Enter], remaining is Fe and relict element.It comprises the technical steps that：

A. converter smelting：Ensure the C >=0.05% that taps, P≤0.006%, tapping temperature >=1580 DEG C；Avoid tapping process slag ；

B. LF is refined：Ensure the control of white slag retention time in 20min or more；The secondary de- P of progress before LF stoves are outbound, control P≤ 0.004%；LF refining carries out Calcium treatment before terminating；

C. VD vacuum refinings：Guarantor's vacuum time >=20min at≤67Pa；

D. continuous casting：Continuous casting uses section for 260mm or 300mm, and continuous casting carries out whole process protection casting, and pouring temperature presses liquidus curve temperature Degree+(25~35 DEG C) controls；

E. heating of plate blank：Cold 16 ~ 20 hours temperature of heap send shove charge after slab is offline；Slab is heated in stepping furnace, temperature control System is at 1180 ~ 1230 DEG C；

F. controlled rolling：It is rolled using CR modes, 1050~1150 DEG C of start rolling temperature；One 950 DEG C of stage finishing temperature ＞ is protected Three percentage pass reductions are 16% or more after card；For two-stage start rolling temperature at 880 ~ 910 DEG C, finish rolling adds up reduction ratio ＞ 48%, finish to gauge Temperature >=860 DEG C；

G. direct quenching：Enter coolant-temperature gage >=850 DEG C, 200 DEG C of red temperature ＜, cooling rate is controlled in 3~8 DEG C/S；

H. it is heat-treated：Using tempering process, 700 ~ 730 DEG C of temperature, 3 ~ 5min/mm of soaking time.

According to four embodiment 14Cr1MoR finished steels that the above method is tested, chemical composition such as table 1, mechanics properties testing The results are shown in Table 2.T is steel plate thickness in table, and Max.PWHT is maximum analog post weld heat treatment.

1 embodiment chemical composition of table（wt.%）

2 embodiment mechanics properties testing result of table

Product surface quality is excellent, outer inspection qualification rate 100%, I grades of flaw detection qualification rates 100%, 100%. steel plate ingredient of properties percent of pass Middle control of deleterious element is stringent, and the J controls of temper embrittlement coefficient are below 90.Steel plate end to end sample through maximum analog postwelding heat at It manages, yield strength surplus capacity is in 100Mpa or more at plate thickness 1/2, and tensile strength surplus capacity is in 30~80Mpa, -18 DEG C of impact bases , in 100J or more, 14Cr1MoR products fully meet GB/T713-2014 and face the associated specifications of hydrogen steel for this.

Claims (1)

1. a kind of production method of 14 CrlMoR Steel Plate used for Hydrogen-contacting Equipment uses process route for converter smelting → LF refining → VD Vacuum refining → continuous casting → heating of plate blank → controlled rolling → direct quenching → heat treatment, it is characterised in that：The chemical composition of steel Mass percent be C=0.10~0.15, Si=0.50~0.60, Mn=0.40~0.60, P≤0.007, S≤0.005, Alt= 0.020~0.050, Cr=1.20~1.50, Mo=0.50~0.65, Ti=0.01 ~ 0.02, Ni=0.10 ~ 0.15, Sn≤0.005, J coefficients=(Si+Mn) ×（P+Sn）×10⁴≤ 120, remaining is Fe and relict element；It comprises the technical steps that：

A. converter smelting：Tap C >=0.05%, P≤0.006%, tapping temperature >=1580 DEG C；Avoid tapping process slag；

B. LF is refined：The white slag retention time controls in 20min or more；The secondary de- P of progress before LF stoves are outbound, control P≤ 0.004%；LF refining carries out Calcium treatment before terminating；

C. VD vacuum refinings：Guarantor's vacuum time >=20min at≤67Pa；

D. continuous casting：Continuous casting uses section for 260mm or 300mm, and continuous casting carries out whole process protection casting, and pouring temperature presses liquidus curve temperature Degree+(25~35 DEG C) controls；

E. heating of plate blank：Temperature send shove charge, slab to be heated in stepping furnace after the cold 16 ~ 20h of heap after slab is offline, temperature control System is at 1180 ~ 1230 DEG C；

F. controlled rolling：It is rolled using CR modes, 1050~1150 DEG C of start rolling temperature；One 950 DEG C of stage finishing temperature ＞ is protected Three percentage pass reductions are 16% or more after card；For two-stage start rolling temperature at 880 ~ 910 DEG C, finish rolling adds up reduction ratio ＞ 48%, finish to gauge Temperature >=860 DEG C；

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

H. it is heat-treated：Using tempering process, 700 ~ 730 DEG C of temperature, 3 ~ 5min/mm of soaking time.