CN114406003A - Preparation method of high-grade ultra-supercritical boiler tube - Google Patents
Preparation method of high-grade ultra-supercritical boiler tube Download PDFInfo
- Publication number
- CN114406003A CN114406003A CN202210139996.9A CN202210139996A CN114406003A CN 114406003 A CN114406003 A CN 114406003A CN 202210139996 A CN202210139996 A CN 202210139996A CN 114406003 A CN114406003 A CN 114406003A
- Authority
- CN
- China
- Prior art keywords
- heating
- rolling
- blank
- intermediate pipe
- pipe blank
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 238000010438 heat treatment Methods 0.000 claims abstract description 122
- 238000005096 rolling process Methods 0.000 claims abstract description 68
- 239000002253 acid Substances 0.000 claims abstract description 22
- 238000005238 degreasing Methods 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims abstract description 21
- 230000010485 coping Effects 0.000 claims abstract description 11
- 238000005554 pickling Methods 0.000 claims abstract description 7
- 238000004080 punching Methods 0.000 claims abstract description 6
- 238000005406 washing Methods 0.000 claims description 30
- 238000004321 preservation Methods 0.000 claims description 21
- 230000003746 surface roughness Effects 0.000 claims description 20
- 238000001816 cooling Methods 0.000 claims description 10
- 239000003921 oil Substances 0.000 claims description 10
- 239000010731 rolling oil Substances 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 230000007547 defect Effects 0.000 claims description 8
- 229910000831 Steel Inorganic materials 0.000 claims description 6
- 238000007689 inspection Methods 0.000 claims description 6
- 239000010959 steel Substances 0.000 claims description 6
- 238000004512 die casting Methods 0.000 claims description 5
- 150000004965 peroxy acids Chemical class 0.000 claims description 5
- 230000000630 rising effect Effects 0.000 claims description 5
- 238000010079 rubber tapping Methods 0.000 claims description 5
- 230000007306 turnover Effects 0.000 claims description 5
- 239000004576 sand Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 239000013078 crystal Substances 0.000 abstract description 6
- 229910000963 austenitic stainless steel Inorganic materials 0.000 abstract description 3
- 238000005097 cold rolling Methods 0.000 abstract description 2
- 230000008676 import Effects 0.000 abstract description 2
- 239000000047 product Substances 0.000 description 13
- 239000011265 semifinished product Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- 238000002604 ultrasonography Methods 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 2
- 230000004807 localization Effects 0.000 description 2
- 238000010923 batch production Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B19/00—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
- B21B19/02—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
- B21B19/04—Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/78—Control of tube rolling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/004—Heating the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0269—Cleaning
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/20—Accessories: Details
- B22D17/22—Dies; Die plates; Die supports; Cooling equipment for dies; Accessories for loosening and ejecting castings from dies
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
A preparation method of a high-grade ultra-supercritical boiler tube belongs to the technical field of tube preparation, and solves the technical problems of inner and outer surface damage caused by rolling, a large number of strip-shaped crystal grains on the inner surface, mixed crystal on the outer surface and the like in the production process of an S30432 economic austenitic stainless steel tube, and comprises the following steps: preparing a punched blank → heating in an inclined bottom furnace → obliquely rolling and punching → straightening, primary acid pickling and coping → first-pass rolling and degreasing → high-temperature softening → second-pass rolling and degreasing → heat treatment and acid pickling to obtain a finished product of the high-grade ultra-supercritical boiler tube. The invention improves the yield of the pierced billet to about 98 percent, the quality of the inner surface and the outer surface of the pierced billet can completely meet the requirement of a cold rolling procedure, the qualified rate of the grain size of the finished product is about 95 percent, the high-grade ultra-supercritical boiler tube of S30432 realizes the national production and the replacement of import, and the production cost is reduced.
Description
Technical Field
The invention belongs to the technical field of pipe preparation, and particularly relates to a preparation method of a high-grade ultra-supercritical boiler pipe.
Background
S30432 has been monopolized by European and American countries such as Japan, Spain, Germany, etc. before being used as an economical austenitic stainless steel. In China, a large amount of stainless steel pipes made of the material are used on super (supercritical) critical boiler superheaters and reheaters, and the stainless steel pipes are always imported. The development of the ultra-supercritical unit in China is quite rapid, the demand of related materials is greatly increased, the localization of key materials is urgently needed, and the defects of rolling damage on the inner surface and the outer surface, a large amount of strip-shaped crystal grains on the inner surface, mixed crystal on the outer surface and the like often occur in the process of producing stainless steel pipes in the localization mode.
The method commonly adopted for domestic production of S30432 boiler tube pierced billets at present has the following defects:
1. the production is carried out by adopting a horizontal extrusion method: although the produced pierced billet has a good outer surface, the yield of the pierced billet is only about 80% due to the existence of residual compression and residual expansion in the extrusion process, and the production cost is high;
2. the method for producing the steel plate by the cross piercing comprises the following steps: although the yield of the pierced billet is high, the phenomena of piercing and rolling cracks and grain size which cannot meet the requirements of customers often occur in the piercing and rolling processes.
Disclosure of Invention
The invention aims to overcome the defects of the background technology, solve the technical problems of inner and outer surface damage caused by rolling, a large number of band-shaped crystal grains on the inner surface, mixed crystal on the outer surface and the like in the production process of an S30432 economic austenitic stainless steel tube, and provide a preparation method of a high-grade ultra-supercritical boiler tube.
The invention is realized by the following technical scheme.
A preparation method of a high-grade ultra-supercritical boiler tube comprises the following steps:
s1, preparing a punched blank: the molten steel is rolled into a bar stock after die casting and blooming, and the bar stock is peeled and centered to prepare a perforated blank;
s2, feeding the punched blank into an inclined hearth furnace to be heated, wherein the heating speed is (4-10) DEG C/min:
heating the inclined hearth furnace for one section: 600 ℃ and 850 ℃, and the heating time is 2 h;
and (3) heating a second section by an inclined hearth furnace: 850 ℃ and 1000 ℃, and the heating time is 3 h;
and (3) heating by an inclined hearth furnace for three sections: 1050 ℃ at 1000 ℃, and the heating time is 0.7 h;
and (3) heating by an inclined hearth furnace in four sections: 1150-1200 ℃, and the heating time is 0.5 h;
the tapping target temperature of the inclined hearth furnace is 1150-1200 ℃;
s3, oblique piercing: the upper and lower working rolls and the left and right guide plates are respectively adjusted to a preset angle, the punched blank is subjected to cross rolling and punching under the action of a pusher and a mandril, the rolling current is 900 plus 1000A, and the rolling time is 1-2min, so as to obtain a pierced billet;
s4, straightening, primary acid washing and coping: straightening the pierced billet by a straightening machine to obtain a pierced billet with the flatness of 3-6mm/m, and then sequentially carrying out a pickling process and a coping process on the pierced billet to ensure that the roughness of the inner surface and the outer surface of the pierced billet is 10-15 mu m;
s5, first rolling and degreasing:
and (4) carrying out first rolling on the pierced billet prepared in the step S4: the maximum rolling force is 150-200t, the rolling elongation coefficient is 5-9, the rolling feed amount is 10-28 mm/time, and a primary intermediate pipe blank is prepared; the surface roughness of the primary intermediate pipe blank is 0.8-3.2 mu m, the flatness is 2-5mm/m, the tolerance of the outer diameter is +/-0.5%, and the tolerance of the wall thickness is +/-5%;
then, degreasing the primary intermediate pipe blank to ensure that the rolling oil on the inner surface and the outer surface of the primary intermediate pipe blank is completely removed, and the inner surface and the outer surface are free from oil stains after washing;
s6, softening at high temperature:
feeding the primary intermediate pipe blank into a chamber furnace for heating at the temperature of 950 and 1050 ℃ for 10-20 min; then entering a temperature rising section, wherein the heating temperature is 1050 ℃ and 1200 ℃, and the heating time is 15-25 min; then entering a heat preservation section, heating to 1250-;
s7, second-pass rolling and degreasing:
and (5) performing second-pass rolling on the semi-finished tube blank prepared in the step S2: the maximum rolling force is 100-150t, the rolling elongation coefficient is 3-8, and a secondary intermediate pipe blank is prepared; the surface roughness of the secondary intermediate pipe blank is 0.4-3.2 mu m, and the flatness is 2-3 mm/m;
then, degreasing the secondary intermediate tube blank to ensure that rolling oil on the inner surface and the outer surface of the tube blank is completely removed, and no oil stain is generated on the inner surface and the outer surface after washing;
s8, heat treatment and acid washing
And (4) feeding the secondary intermediate pipe blank prepared in the step S7 into a heat treatment furnace for heating:
heating the heat treatment furnace for one section: the heating temperature is 1000-;
heating a second section of the heat treatment furnace: the heating temperature is 1100-;
heat preservation section of heat treatment furnace: the heat preservation temperature is 1150-sand 1180 ℃, and the heat preservation time is 20-30 min;
and taking out the secondary intermediate pipe blank after the heat preservation is finished, quickly cooling the secondary intermediate pipe blank to room temperature by water, taking out the secondary intermediate pipe blank for acid washing, and ensuring that the inner surface and the outer surface of the secondary intermediate pipe blank have no mottling and peracid phenomena in the acid washing process to obtain a high-grade ultra-supercritical boiler pipe finished product.
Further, in the step S1, the length of the bar stock is 6 to 8m, the surface roughness is 13 to 16um, and the roundness is 0.035 to 0.045 mm; the length of the punched blank is 1000-2000mm, the outer diameter is phi 80-110mm, and the surface roughness is 6-10 um.
Further, in the step S2, the turnover of the furnace door during the heating process of the inclined hearth furnace ensures that the furnace door is turned over at an angle of 180 degrees at a time.
Further, in the step S3, the grain size of the pierced billet is grade 2-8.
Further, in the step S6, the grain size of the semi-finished tube blank is 0 to 7 grade.
Further, in the step S8, the grain size of the secondary intermediate pipe blank after the rapid water cooling is 7 to 10 grades and the inner surface has no band-like grains.
Further, after the step S8, surface inspection is performed, and then the quality of the outer surface and the inner surface of the finished product pipe is inspected by ultrasonic and eddy current, so as to ensure that the quality of the finished product surface and the inner wall of the high-grade ultra-supercritical boiler pipe is free from defects.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a preparation method of a high-grade ultra-supercritical boiler tube on the basis of hot rolling perforation, which improves the yield of a pierced billet to about 98 percent, ensures that the quality of the inner surface and the outer surface of the pierced billet can completely meet the requirement of a cold rolling process, ensures that the grain size qualification rate of a finished product is about 95 percent, greatly improves the yield of boiler tubes of various specifications S30432 in batch production, realizes national productization and import replacement, and reduces the production cost.
Detailed Description
The present invention will be described in further detail with reference to examples.
Example 1
A preparation method of a high-grade ultra-supercritical boiler tube comprises the following steps:
s1, preparing a punched blank: the molten steel is rolled into a bar stock after die casting and blooming, the length of the bar stock is 6m, the surface roughness is 13um, and the roundness is 0.035 mm; peeling and centering the bar stock to prepare a punched blank, wherein the length of the punched blank is 1000mm, the outer diameter of the punched blank is phi 80mm, and the surface roughness of the punched blank is 6 um;
s2, feeding the punched blank into an inclined hearth furnace for heating, and turning over the furnace door in a turnover manner to ensure that the blank is turned over at an angle of 100 degrees each time in the heating process of the inclined hearth furnace:
heating the inclined hearth furnace for one section: heating at 600 deg.C for 2 h;
and (3) heating a second section by an inclined hearth furnace: heating at 850 deg.C for 3 h;
and (3) heating by an inclined hearth furnace for three sections: heating at 1000 deg.C for 0.7 h;
and (3) heating by an inclined hearth furnace in four sections: heating at 1150 deg.C for 0.5 h;
the tapping target temperature of the inclined hearth furnace is 1150 ℃;
s3, oblique piercing: the upper working roll, the lower working roll, the left guide plate and the right guide plate are respectively adjusted to preset angles, the punched blank is subjected to cross rolling and punching under the action of a pusher and a mandril, the rolling current is 900A, the rolling time is 1min, and pierced billets are prepared, wherein the grain size of the pierced billets is grade 2;
s4, straightening, primary acid washing and coping: straightening the pierced billet by a straightening machine to obtain a pierced billet with the straightness of 3mm/m, and then sequentially carrying out a pickling process and a coping process on the pierced billet to ensure that the roughness of the inner surface and the outer surface of the pierced billet is 10 mu m;
s5, first rolling and degreasing:
and (4) carrying out first rolling on the pierced billet prepared in the step S4: the maximum rolling force is 150t, the rolling elongation coefficient is 5, and the rolling feed amount is 10 mm/time, so that a primary intermediate pipe blank is manufactured; the surface roughness of the primary intermediate pipe blank is 0.8 mu m, the flatness is 2mm/m, the tolerance of the outer diameter is +/-0.5%, and the tolerance of the wall thickness is +/-5%;
then, degreasing the primary intermediate pipe blank to ensure that the rolling oil on the inner surface and the outer surface of the primary intermediate pipe blank is completely removed, and the inner surface and the outer surface are free from oil stains after washing;
s6, softening at high temperature:
feeding the primary intermediate pipe blank into a chamber furnace for heating at 950 ℃ for 10 min; then entering a temperature rising section, wherein the heating temperature is 1050 ℃, and the heating time is 15 min; then entering a heat preservation section, heating at 1250 ℃, preserving heat for 10min, and preparing a semi-finished product tube blank, wherein the grain size of the semi-finished product tube blank is grade 2;
s7, second-pass rolling and degreasing:
and (5) performing second-pass rolling on the semi-finished tube blank prepared in the step S2: the maximum rolling force is 100t, the rolling elongation coefficient is 3, and a secondary intermediate pipe blank is manufactured; the surface roughness of the secondary intermediate pipe blank is 0.4 mu m, and the flatness is 2 mm/m;
then, degreasing the secondary intermediate tube blank to ensure that rolling oil on the inner surface and the outer surface of the tube blank is completely removed, and no oil stain is generated on the inner surface and the outer surface after washing;
s8, heat treatment and acid washing
And (4) feeding the secondary intermediate pipe blank prepared in the step S7 into a heat treatment furnace for heating:
heating the heat treatment furnace for one section: heating at 1000 deg.C for 5 min;
heating a second section of the heat treatment furnace: heating at 1100 deg.C for 15 min;
heat preservation section of heat treatment furnace: the heat preservation temperature is 1150 ℃, and the heat preservation time is 20 min;
taking out the secondary intermediate pipe blank after the heat preservation is finished, and quickly cooling the secondary intermediate pipe blank to room temperature by water, wherein the grain size of the secondary intermediate pipe blank after the quick water cooling is grade 7 and the inner surface of the secondary intermediate pipe blank has no banded grains; then taking out the secondary intermediate tube blank for acid washing, wherein the acid washing process ensures that the inner and outer surfaces have no mottling and peracid phenomena, and a high-grade ultra-supercritical boiler tube finished product is prepared;
and S9, performing surface inspection, and inspecting the quality of the outer surface and the inner surface of the finished product pipe through ultrasound and eddy current to ensure that the quality of the finished product surface and the inner wall of the high-grade ultra-supercritical boiler pipe is free from defects.
Example 2
A preparation method of a high-grade ultra-supercritical boiler tube comprises the following steps:
s1, preparing a punched blank: the molten steel is rolled into a bar stock after die casting and blooming, the length of the bar stock is 7m, the surface roughness is 15um, and the roundness is 0.040 mm; peeling and centering the bar stock to prepare a punched blank, wherein the length of the punched blank is 1300mm, the outer diameter is phi 100mm, and the surface roughness is 8 um;
s2, feeding the punched blank into an inclined hearth furnace for heating, and turning over the furnace door in a turnover manner to ensure that the blank is turned over at an angle of 120 degrees each time in the heating process of the inclined hearth furnace:
heating the inclined hearth furnace for one section: heating for 2h at 800 ℃;
and (3) heating a second section by an inclined hearth furnace: heating at 900 deg.C for 3 h;
and (3) heating by an inclined hearth furnace for three sections: 1020, the heating time is 0.7 h;
and (3) heating by an inclined hearth furnace in four sections: 1175 ℃, and the heating time is 0.5 h;
the tapping target temperature of the inclined hearth furnace is 1175 ℃;
s3, oblique piercing: the upper working roll, the lower working roll, the left guide plate and the right guide plate are respectively adjusted to preset angles, the punched blank is subjected to cross rolling and punching under the action of a pusher and a mandril, the rolling current is 950A, the rolling time is 1.5min, and a pierced billet is prepared, wherein the grain size of the pierced billet is grade 6;
s4, straightening, primary acid washing and coping: straightening the pierced billet by a straightening machine to obtain a pierced billet with the straightness of 5mm/m, and then sequentially carrying out a pickling process and a coping process on the pierced billet to ensure that the roughness of the inner surface and the outer surface of the pierced billet is 12 mu m;
s5, first rolling and degreasing:
and (4) carrying out first rolling on the pierced billet prepared in the step S4: the maximum rolling force is 180t, the rolling elongation coefficient is 7, and the rolling feed amount is 20 mm/time, so that a primary intermediate pipe blank is manufactured; the surface roughness of the primary intermediate pipe blank is 1.6 mu m, the flatness is 3mm/m, the tolerance of the outer diameter is +/-0.5%, and the tolerance of the wall thickness is +/-5%;
then, degreasing the primary intermediate pipe blank to ensure that the rolling oil on the inner surface and the outer surface of the primary intermediate pipe blank is completely removed, and the inner surface and the outer surface are free from oil stains after washing;
s6, softening at high temperature:
feeding the primary intermediate pipe blank into a chamber furnace for heating at 1000 ℃ for 15 min; then entering a temperature rising section, wherein the heating temperature is 1100 ℃, and the heating time is 20 min; then entering a heat preservation section, heating at 1270 ℃, preserving heat for 15min, and preparing a semi-finished product pipe blank, wherein the grain size of the semi-finished product pipe blank is grade 3;
s7, second-pass rolling and degreasing:
and (5) performing second-pass rolling on the semi-finished tube blank prepared in the step S2: the maximum rolling force is 130t, the rolling elongation coefficient is 5, and a secondary intermediate pipe blank is prepared; the surface roughness of the secondary intermediate pipe blank is 0.8 mu m, and the flatness is 2.5 mm/m;
then, degreasing the secondary intermediate tube blank to ensure that rolling oil on the inner surface and the outer surface of the tube blank is completely removed, and no oil stain is generated on the inner surface and the outer surface after washing;
s8, heat treatment and acid washing
And (4) feeding the secondary intermediate pipe blank prepared in the step S7 into a heat treatment furnace for heating:
heating the heat treatment furnace for one section: heating at 1050 deg.C for 8 min;
heating a second section of the heat treatment furnace: heating at 1130 deg.C for 18 min;
heat preservation section of heat treatment furnace: keeping the temperature at 1160 deg.C for 25 min;
taking out the secondary intermediate pipe blank after the heat preservation is finished, and quickly cooling the secondary intermediate pipe blank to room temperature by water, wherein the grain size of the secondary intermediate pipe blank after the quick water cooling is grade 8 and the inner surface of the secondary intermediate pipe blank has no banded grains; then taking out the secondary intermediate tube blank for acid washing, wherein the acid washing process ensures that the inner and outer surfaces have no mottling and peracid phenomena, and a high-grade ultra-supercritical boiler tube finished product is prepared;
and S9, performing surface inspection, and inspecting the quality of the outer surface and the inner surface of the finished product pipe through ultrasound and eddy current to ensure that the quality of the finished product surface and the inner wall of the high-grade ultra-supercritical boiler pipe is free from defects.
Example 3
A preparation method of a high-grade ultra-supercritical boiler tube comprises the following steps:
s1, preparing a punched blank: the molten steel is rolled into a bar stock after die casting and blooming, the length of the bar stock is 8m, the surface roughness is 16um, and the roundness is 0.045 mm; peeling and centering the bar stock to prepare a punched blank, wherein the length of the punched blank is 2000mm, the outer diameter of the punched blank is phi 110mm, and the surface roughness of the punched blank is 10 mu m;
s2, feeding the punched blank into an inclined hearth furnace for heating, and turning over the furnace door in a turnover manner to ensure that the blank is turned over at an angle of 180 degrees each time in the heating process of the inclined hearth furnace:
heating the inclined hearth furnace for one section: heating at 850 deg.C for 2 h;
and (3) heating a second section by an inclined hearth furnace: heating for 3h at 1000 ℃;
and (3) heating by an inclined hearth furnace for three sections: heating at 1050 deg.C for 0.7 h;
and (3) heating by an inclined hearth furnace in four sections: heating at 1200 deg.C for 0.5 h;
the tapping target temperature of the inclined hearth furnace is 1200 ℃;
s3, oblique piercing: the upper working roll, the lower working roll, the left guide plate and the right guide plate are respectively adjusted to preset angles, the punched blank is subjected to cross rolling and punching under the action of a pusher and a mandril, the rolling current is 1000A, the rolling time is 2min, and pierced billets are prepared, wherein the grain size of the pierced billets is 8 grades;
s4, straightening, primary acid washing and coping: straightening the pierced billet by a straightening machine to obtain a pierced billet with the flatness of 6mm/m, and then sequentially carrying out a pickling process and a coping process on the pierced billet to ensure that the roughness of the inner surface and the outer surface of the pierced billet is 15 mu m;
s5, first rolling and degreasing:
and (4) carrying out first rolling on the pierced billet prepared in the step S4: the maximum rolling force is 200t, the rolling elongation coefficient is 9, and the rolling feed amount is 28 mm/time, so that a primary intermediate pipe blank is prepared; the surface roughness of the primary intermediate pipe blank is 3.2 mu m, the flatness is 5mm/m, the tolerance of the outer diameter is +/-0.5%, and the tolerance of the wall thickness is +/-5%;
then, degreasing the primary intermediate pipe blank to ensure that the rolling oil on the inner surface and the outer surface of the primary intermediate pipe blank is completely removed, and the inner surface and the outer surface are free from oil stains after washing;
s6, softening at high temperature:
feeding the primary intermediate pipe blank into a chamber furnace for heating at 1050 ℃ for 20 min; then entering a temperature rising section, wherein the heating temperature is 1200 ℃, and the heating time is 25 min; then entering a heat preservation section, heating at 1270 ℃, preserving heat for 20min, and preparing a semi-finished product tube blank, wherein the grain size of the semi-finished product tube blank is grade 7;
s7, second-pass rolling and degreasing:
and (5) performing second-pass rolling on the semi-finished tube blank prepared in the step S2: the maximum rolling force is 150t, the rolling elongation coefficient is 8, and a secondary intermediate pipe blank is manufactured; the surface roughness of the secondary intermediate pipe blank is 3.2 mu m, and the flatness is 3 mm/m;
then, degreasing the secondary intermediate tube blank to ensure that rolling oil on the inner surface and the outer surface of the tube blank is completely removed, and no oil stain is generated on the inner surface and the outer surface after washing;
s8, heat treatment and acid washing
And (4) feeding the secondary intermediate pipe blank prepared in the step S7 into a heat treatment furnace for heating:
heating the heat treatment furnace for one section: heating at 1100 deg.C for 10 min;
heating a second section of the heat treatment furnace: heating at 1150 deg.C for 20 min;
heat preservation section of heat treatment furnace: keeping the temperature at 1170 ℃ for 30 min;
taking out the secondary intermediate pipe blank after the heat preservation is finished, and quickly cooling the secondary intermediate pipe blank to room temperature by water, wherein the grain size of the secondary intermediate pipe blank after the quick water cooling is grade 8 and the inner surface of the secondary intermediate pipe blank has no banded grains; then taking out the secondary intermediate tube blank for acid washing, wherein the acid washing process ensures that the inner and outer surfaces have no mottling and peracid phenomena, and a high-grade ultra-supercritical boiler tube finished product is prepared;
and S9, performing surface inspection, and inspecting the quality of the outer surface and the inner surface of the finished product pipe through ultrasound and eddy current to ensure that the quality of the finished product surface and the inner wall of the high-grade ultra-supercritical boiler pipe is free from defects.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (7)
1. A preparation method of a high-grade ultra-supercritical boiler tube is characterized by comprising the following steps:
s1, preparing a punched blank: the molten steel is rolled into a bar stock after die casting and blooming, and the bar stock is peeled and centered to prepare a perforated blank;
s2, feeding the punched blank into an inclined hearth furnace to be heated, wherein the heating speed is (4-10) DEG C/min:
heating the inclined hearth furnace for one section: 600 ℃ and 850 ℃, and the heating time is 2 h;
and (3) heating a second section by an inclined hearth furnace: 850 ℃ and 1000 ℃, and the heating time is 3 h;
and (3) heating by an inclined hearth furnace for three sections: 1050 ℃ at 1000 ℃, and the heating time is 0.7 h;
and (3) heating by an inclined hearth furnace in four sections: 1150-1200 ℃, and the heating time is 0.5 h;
the tapping target temperature of the inclined hearth furnace is 1150-1200 ℃;
s3, oblique piercing: the upper and lower working rolls and the left and right guide plates are respectively adjusted to a preset angle, the punched blank is subjected to cross rolling and punching under the action of a pusher and a mandril, the rolling current is 900 plus 1000A, and the rolling time is 1-2min, so as to obtain a pierced billet;
s4, straightening, primary acid washing and coping: straightening the pierced billet by a straightening machine to obtain a pierced billet with the flatness of 3-6mm/m, and then sequentially carrying out a pickling process and a coping process on the pierced billet to ensure that the roughness of the inner surface and the outer surface of the pierced billet is 10-15 mu m;
s5, first rolling and degreasing:
and (4) carrying out first rolling on the pierced billet prepared in the step S4: the maximum rolling force is 150-200t, the rolling elongation coefficient is 5-9, the rolling feed amount is 10-28 mm/time, and a primary intermediate pipe blank is prepared; the surface roughness of the primary intermediate pipe blank is 0.8-3.2 mu m, the flatness is 2-5mm/m, the tolerance of the outer diameter is +/-0.5%, and the tolerance of the wall thickness is +/-5%;
then, degreasing the primary intermediate pipe blank to ensure that the rolling oil on the inner surface and the outer surface of the primary intermediate pipe blank is completely removed, and the inner surface and the outer surface are free from oil stains after washing;
s6, softening at high temperature:
feeding the primary intermediate pipe blank into a chamber furnace for heating at the temperature of 950 and 1050 ℃ for 10-20 min; then entering a temperature rising section, wherein the heating temperature is 1050 ℃ and 1200 ℃, and the heating time is 15-25 min; then entering a heat preservation section, heating to 1250-;
s7, second-pass rolling and degreasing:
and (5) performing second-pass rolling on the semi-finished tube blank prepared in the step S2: the maximum rolling force is 100-150t, the rolling elongation coefficient is 3-8, and a secondary intermediate pipe blank is prepared; the surface roughness of the secondary intermediate pipe blank is 0.4-3.2 mu m, and the flatness is 2-3 mm/m;
then, degreasing the secondary intermediate tube blank to ensure that rolling oil on the inner surface and the outer surface of the tube blank is completely removed, and no oil stain is generated on the inner surface and the outer surface after washing;
s8, heat treatment and acid washing
And (4) feeding the secondary intermediate pipe blank prepared in the step S7 into a heat treatment furnace for heating:
heating the heat treatment furnace for one section: the heating temperature is 1000-;
heating a second section of the heat treatment furnace: the heating temperature is 1100-;
heat preservation section of heat treatment furnace: the heat preservation temperature is 1150-sand 1180 ℃, and the heat preservation time is 20-30 min;
and taking out the secondary intermediate pipe blank after the heat preservation is finished, quickly cooling the secondary intermediate pipe blank to room temperature by water, taking out the secondary intermediate pipe blank for acid washing, and ensuring that the inner surface and the outer surface of the secondary intermediate pipe blank have no mottling and peracid phenomena in the acid washing process to obtain a high-grade ultra-supercritical boiler pipe finished product.
2. The method for preparing a high-grade ultra supercritical boiler tube according to claim 1, wherein: in the step S1, the length of the bar stock is 6-8m, the surface roughness is 13-16um, and the roundness is 0.035-0.045 mm; the length of the punched blank is 1000-2000mm, the outer diameter is phi 80-110mm, and the surface roughness is 6-10 um.
3. The method for preparing a high-grade ultra supercritical boiler tube according to claim 1, wherein: in the step S2, the turnover of the furnace door during the heating process of the inclined hearth furnace ensures that the furnace door is turned over at an angle of 100 degrees and 180 degrees each time.
4. The method for preparing a high-grade ultra supercritical boiler tube according to claim 1, wherein: in the step S3, the grain size of the pierced billet is grade 2-8.
5. The method for preparing a high-grade ultra supercritical boiler tube according to claim 1, wherein: in the step S6, the grain size of the semi-finished tube blank is 0 to 7 grade.
6. The method for preparing a high-grade ultra supercritical boiler tube according to claim 1, wherein: in the step S8, the grain size of the secondary intermediate pipe blank after the rapid water cooling is 7 to 10 grades and the inner surface has no band-like grains.
7. The method for preparing a high-grade ultra supercritical boiler tube according to claim 1, wherein: and performing surface inspection after the step S8, and then performing ultrasonic and eddy current inspection on the quality of the outer surface and the inner surface of the finished product pipe to ensure that the quality of the finished product surface and the inner wall of the high-grade ultra-supercritical boiler pipe is free from defects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210139996.9A CN114406003B (en) | 2022-02-14 | 2022-02-14 | Preparation method of high-grade ultra-supercritical boiler tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210139996.9A CN114406003B (en) | 2022-02-14 | 2022-02-14 | Preparation method of high-grade ultra-supercritical boiler tube |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114406003A true CN114406003A (en) | 2022-04-29 |
| CN114406003B CN114406003B (en) | 2024-06-25 |
Family
ID=81261914
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210139996.9A Active CN114406003B (en) | 2022-02-14 | 2022-02-14 | Preparation method of high-grade ultra-supercritical boiler tube |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114406003B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101781743A (en) * | 2010-02-26 | 2010-07-21 | 山西太钢不锈钢股份有限公司 | Seamless steel tube for ultra supercritical boiler and manufacturing method thereof |
| CN102059271A (en) * | 2010-11-23 | 2011-05-18 | 攀钢集团钢铁钒钛股份有限公司 | Manufacture method of seamless steel tube for (ultra-)supercritical boiler |
| RU2012139548A (en) * | 2012-09-14 | 2014-03-20 | Открытое акционерное общество "Челябинский трубопрокатный завод" | METHOD FOR PRODUCING SEAMLESS HOT-ROLLED LONG-DIMENSIONAL PIPES OF 465 × 75 mm SIZE FOR STEAM BOILERS, STEAM PIPES AND MANIFOLDS OF INSTALLATIONS WITH HIGH AND SUPER CRITICAL SILVER PERFORMANCE |
| RU2013112284A (en) * | 2013-07-11 | 2015-01-20 | Открытое акционерное общество "Челябинский трубопрокатный завод" | METHOD FOR PRODUCING SEAMLESS PIPES SIZED 426 × 15-60 mm FOR STEAM BOILERS, STEAM PIPELINES AND MANIFOLDERS OF UNITS WITH HIGH AND SUPERCRITICAL STEAM PARAMETERS FROM STEEL 10H9MFB-SH STEEL |
-
2022
- 2022-02-14 CN CN202210139996.9A patent/CN114406003B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101781743A (en) * | 2010-02-26 | 2010-07-21 | 山西太钢不锈钢股份有限公司 | Seamless steel tube for ultra supercritical boiler and manufacturing method thereof |
| CN102059271A (en) * | 2010-11-23 | 2011-05-18 | 攀钢集团钢铁钒钛股份有限公司 | Manufacture method of seamless steel tube for (ultra-)supercritical boiler |
| RU2012139548A (en) * | 2012-09-14 | 2014-03-20 | Открытое акционерное общество "Челябинский трубопрокатный завод" | METHOD FOR PRODUCING SEAMLESS HOT-ROLLED LONG-DIMENSIONAL PIPES OF 465 × 75 mm SIZE FOR STEAM BOILERS, STEAM PIPES AND MANIFOLDS OF INSTALLATIONS WITH HIGH AND SUPER CRITICAL SILVER PERFORMANCE |
| RU2013112284A (en) * | 2013-07-11 | 2015-01-20 | Открытое акционерное общество "Челябинский трубопрокатный завод" | METHOD FOR PRODUCING SEAMLESS PIPES SIZED 426 × 15-60 mm FOR STEAM BOILERS, STEAM PIPELINES AND MANIFOLDERS OF UNITS WITH HIGH AND SUPERCRITICAL STEAM PARAMETERS FROM STEEL 10H9MFB-SH STEEL |
Non-Patent Citations (3)
| Title |
|---|
| 彭声通: "超(超)临界锅炉用10Cr18Ni9NbCu3BN钢制管工艺研究", 特钢技术, vol. 20, no. 2, pages 19 - 24 * |
| 彭芳芳;朱国良;宋建新;: "超(超)临界机组用SUPER304H管国产化关键制造工艺分析", 东方电气评论, no. 04, pages 31 - 33 * |
| 白晋钢;: "电站锅炉用S30432耐热不锈钢管的研制", 山西冶金, no. 04, pages 19 - 20 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114406003B (en) | 2024-06-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102489952B (en) | Method for manufacturing titanium alloy thick-wall pressure-resistant cylinder body | |
| CN102873512B (en) | The manufacture method of thick-walled seamless steel pipes in used in nuclear power station heavy caliber | |
| CN112453104B (en) | Large-caliber thin-wall Ti35 titanium alloy seamless pipe and preparation method thereof | |
| CN111922078B (en) | Production method of high-strength thick steel plate with yield strength of more than or equal to 370MPa | |
| CN105290282B (en) | A kind of manufacture method of superelevation cylinder part | |
| RU2317866C2 (en) | Method for producing cover hexahedral tube-blanks of low-ductile boron-containing steel for compacted storage of waste nuclear fuel | |
| CN112756909A (en) | Preparation method of large-caliber Ti35 titanium alloy pipe | |
| CN114737132A (en) | N06600 iron-nickel base alloy hot continuous rolling plate coil production process | |
| CN103934304A (en) | Forming method of precise high-temperature alloy pipe with small caliber and thick wall for aviation | |
| CN114632837A (en) | Preparation method of spiral heat exchange tube of high-temperature gas cooled reactor steam generator | |
| RU2315672C2 (en) | Rolling method of conversion tubes of large and mean diameters from ingots and billets of titanium base alloys in tube rolling aggregates with pilger mills | |
| CN114406003A (en) | Preparation method of high-grade ultra-supercritical boiler tube | |
| CN106181261B (en) | The manufacture method of thin-wall high intensity frame tube | |
| CN106623419B (en) | The cold rolling production method of controlled expansion alloy band | |
| CN107413883A (en) | A kind of processing method of titanium alloy thin-walled tube stock | |
| CN112453102A (en) | Production and manufacturing process of high-temperature-resistant nickel-based alloy pipe fitting | |
| CN104815845A (en) | Machining method of steel pipe | |
| CN115518999B (en) | Preparation method of zirconium or zirconium alloy thin-wall square tube | |
| CN111842532A (en) | Zirconium alloy pipe preparation method and zirconium alloy pipe prepared based on method | |
| RU2288053C2 (en) | Method for producing cold-rolled large- and mean- diameter tubes of titanium base alloys | |
| CN116254400A (en) | Reinforced heat treatment and processing technology for seamless steel tube | |
| CN117444115A (en) | Precision forging machine-based forging material high-quality forming method | |
| CN110614289A (en) | Slow cooling method for large-scale extruded thick-wall blank made of Ni-Cu alloy heat-resistant steel | |
| RU2306991C2 (en) | Method for producing hot rolled commercial and conversion tubes of large- and mean-diameters of hard-to-form steels and alloys in tube rolling plants with pilger mills | |
| CN112916645A (en) | High-strength steel pipe machining process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |