CN102764960B - Method for manufacturing composite steel plate for hydrogenation reaction kettle barrel - Google Patents
Method for manufacturing composite steel plate for hydrogenation reaction kettle barrel Download PDFInfo
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- CN102764960B CN102764960B CN201210264017.9A CN201210264017A CN102764960B CN 102764960 B CN102764960 B CN 102764960B CN 201210264017 A CN201210264017 A CN 201210264017A CN 102764960 B CN102764960 B CN 102764960B
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- reaction kettle
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Abstract
The invention discloses a method for manufacturing a composite steel plate for a hydrogenation reaction kettle barrel, and belongs to the field of metal materials. The method includes processing a common carbon steel material with the thickness ranging from 300mm to 600mm and a stainless steel material with the thickness ranging from 10mm to 60mm into blanks with identical lengths and identical width at first; overlapping clean surfaces of the blanks; welding peripheries of the blanks by a welding process combining gas shielded welding, submerged arc welding and vacuum electron beam welding; then heating a composite blank welded in the previous step and rolling composite blank by a heavy and medium plate mill to form the carbon steel and stainless steel composite plate with the thickness higher than 100mm; and finally using the carbon steel and composite plate for manufacturing the hydrogenation reaction kettle barrel. The composite steel plate is excellent in physical performance, corrosion resistance and high-pressure resistance, and requirements of manufacture of the hydrogenation reaction kettle barrel are met completely.
Description
Technical field
The invention belongs to metal material field, be specifically related to the manufacture method of a kind of hydrogenation reaction kettle barrel clad steel plate.
Background technology
Along with the continuous progress of science and technology, the required product such as sorbierite, xylitol of the industries such as chemical industry and pharmacy is all to adopt hydrogenation reaction kettle equipment to produce.At present, the maximization of equipment is an inexorable trend of its development, and reactor volume is larger, operating pressure and temperature etc. in production process are required also stricter, as for 30m
3hydrogenation reaction kettle operating pressure requires to reach 15MPa, and operating temperature will reach 200 DEG C.Although general carbon steel and the reactor of enamel structure can meet the requirement of pressure and operating temperature, its decay resistance far can not meet the demand of production; If reactor all adopts stainless steel manufacture, although can meet decay resistance and operating temperature requirement, but its operating pressure does not reach requirement, for its pressure is met design requirement, more than the thickness of stainless steel reaction kettle barrel just must reach 100mm, its cost can increase substantially like this, is the more than three times of ordinary carbon steel.
The technology that adopts the compound sheet material of blast technique to produce hydrogenation reaction kettle barrel by carbon steel layer and stainless steel layer has been proposed in patent CN101584975A " hydrogenation reaction kettle barrel ", can effectively address the above problem, and explosion cladding process is to utilize the enormous impact power of explosive charge generation that bi-material is combined, can produce huge noise, affect surrounding enviroment; Need mother metal performance (toughness, impact property etc.), explosive property (explosion velocity is stable, safety etc.), initial parameter (unit are explosive charge, base compound plate spacing etc.) and dynamic parameter (impingement angle, compound plate impact velocity) etc. and systematic parameter close fit because blast is compound, the yield rate of composite plate and quality are difficult to accurate control simultaneously; Blast composite algorithm production cost is higher, and composite plate size is larger, and explode compound conditional request and cost are just higher, adopts the method production large scale composite plate to be subject to certain restrictions.
Summary of the invention
The present invention is in order to overcome the problems referred to above; the manufacture method of a kind of hydrogenation reaction kettle barrel clad steel plate is provided; adopt gas shielded arc welding, submerged-arc welding and electron-bombardment welding assembled welding process by the ordinary carbon steel blank of thickness 300-600mm and the seam of 10-60mm stainless steel surrounding; the composite blank having welded adopts heavy and medium plate mill to be rolled into carbon steel-stainless steel composite board more than 100mm after heating again, the final manufacture for hydrogenation reaction kettle barrel.Properties of product are good, possess excellent corrosion resistance and high resistance to pressure.
The present invention is achieved through the following technical solutions: the manufacture method of clad steel plate for a kind of hydrogenation reaction kettle barrel, comprises the following steps:
(1) selecting carbon steel blank and the stainless steel blank of surrounding same size (be that length, width equate, thickness can be different) is raw material;
(2) cut by flame or the form finished edge such as plane, milling on three limits of all carbon steel blanks and stainless steel blank being intended to solder side, groove depth 10-40mm, bevel angle 15-35 °; Carbon steel blank and stainless steel blank are stacked together, group aligns together, and half-twist is vertically placed, then adopt the welding manner of gas shielded arc welding, there is the side seam on three faces of groove to carry out bottoming welding to carbon steel blank and stainless steel blank, adopt Lincoln weld to fill and cover welding again, finally the side seam on residue face is carried out under high vacuum to vacuum electron beam welding, assembly welding becomes composite blank;
(3) the composite blank dress bogie-type furnace that butt welding connects or soaking pit heating, tapping temperature is controlled at 1160～1280 DEG C;
(4) come out of the stove after rolling, adopt two-stage rolling, 1000～1150 DEG C of first stage start rolling temperatures, 820～920 DEG C of second stage start rolling temperatures, workpiece thickness is not less than 1.4 times of finished product clad steel plate thickness;
(5) carry out slow cooling to rolling rear clad steel plate.
Described step (1) stainless steel sotck thinkness is 10-60mm, and carbon steel sotck thinkness is 300-600mm.
Described step (2) carbon steel blank and stainless steel blank, by machine-tooled methods such as milling machine, planers, remove iron scale, the greasy dirt etc. on surface to be composite before its welding, realizes surperficial clean.
Described step (2) gas shielded arc welding, its gage of wire 1.2-2.0mm, weldingvoltage 20-35V, welding current 120-400A, speed of welding 250-600mm/min, dry extension of electrode degree 15-25mm, protective gas CO
2or Ar+CO
2, shield gas flow rate 15-25L/min, fusion penetration 5-20mm.
Described step (2) Lincoln weld, its gage of wire 4.0-6.0mm, weldingvoltage 30-45V, welding current 250-1600A, speed of welding 250-600mm/min, dry extension of electrode degree 25-45mm, fusion penetration 10-30mm.
Described step (2) vacuum electron beam welding, its weldingvoltage 30-150KV, vacuum is higher than 1 × 10
-1pa, welding current 100-500mA, speed of welding 50-700mm/min, fusion penetration 20-50mm.
The large thickness blank that butt welding of the present invention connects adopts bogie-type furnace or soaking pit to heat, and suitably increases high temperature section temperature retention time, guarantees that steel plate grills thoroughly, burns evenly.
In the operation of rolling of the present invention, adopt two-stage rolling, carry out high temperature low speed in the first stage and depress greatly rolling, by recrystallization process crystal grain thinning repeatedly; Second stage adopts controlled rolling, increases phase deformed nucleus point crystal grain thinning, and 1.4 times of finished product thicknesses of intermediate blank are the cumulative deformations in order to ensure the two-stage operation of rolling.
The invention has the beneficial effects as follows: compared with the technology of producing hydrogenation reaction kettle barrel carbon steel stainless steel clad plate with existing employing blast complex method, the present invention adopts gas shielded arc welding, submerged-arc welding and electron-bombardment welding assembled welding process, the large thickness blank being welded into can increase the compression ratio of mill product steel plate, therefore carbon steel, stainless compound interface in follow-up thermal processing distortion process after the solid-state diffusion under high temperature, be very easy to combine, form an entirety, the bond strength of compound interface is increased substantially, ensure the stability of product quality.Compare blast composite algorithm, composite technique for rolling equipment is simple simultaneously, and environment is not almost polluted, and can make full use of existing milling train and be rolled.
The assembly welding mode of gas shielded arc welding, submerged-arc welding and electron-bombardment welding, has following advantage:
1, first the present invention adopts gas shielded arc welding to carry out bottoming welding to three side seams of carbon steel and stainless steel slab group, completes automatically and efficiently basis welding, and be that next step submerged-arc welding is ready under the prerequisite of not polluting faying face; Then adopt again the mode of Lincoln weld to complete rapidly the filling welding of weld seam to these three side seams, finally will remain a side seam and apply electron-bombardment welding technique under vacuum environment, complete the final welding of blank.
2, the present invention adopts permanent order to carry out the successively technique of welding; it not the simple combination of gas shielded arc welding, submerged-arc welding and electron-bombardment welding; but the inherent quality requirement of preparing in strict accordance with large thickness slab; take into full account the advantage separately of three kinds of welding manners, by the result of its optimum organization.Can realize automation raising welding efficiency because gas shielded arc welding can not pollute slab group faying face, Lincoln weld is than the more efficient a kind of welding manner of gas shielded arc welding simultaneously, and gas shielded arc welding and submerged-arc welding operation are all carried out under home.This Combination Welding order and mode can increase substantially welding efficiency under the prerequisite that ensures welding requirements (particularly the cleanliness factor of faying face being required), have reduced production cost.
3, the present invention, because slab group is that vertical direction is placed, therefore can ensure to keep between blank the gap of 1mm left and right, and can not form local closed area.Electron-bombardment welding has guaranteed that final being welded in high vacuum completes, and has avoided faying face place to exist air impact to roll the possibility of rear quality.
Brief description of the drawings
Fig. 1 is the compound place's metallographic structure of the carbon steel-stainless steel figure that embodiment 1 produces steel plate.
Implement concrete mode
Below in conjunction with specific embodiment, this kind of hydrogenation reaction kettle barrel is described in detail by the manufacturing process of clad steel plate.
Embodiment 1
Produce the thick carbon steel-stainless steel hydrogenation reaction kettle barrel of 100mm clad steel plate:
1) choose respectively the continuous casting steel billet of the Q235B material that 300mm is thick and the thick 304 stainless steel billets of 40mm as raw material.
2) respectively by three lateral dominance flame cutting method finished edges of selected continuous casting steel billet and stainless steel billet, groove depth 25mm, 25 ° of bevel angles.
3) blank that completes finished edge is processed by milling machine, removed surperficial iron scale, greasy dirt etc., and two blanks are processed into identical length and width size.
4) blank processing is stacked together, group aligns together, and before welding, the continuous casting steel billet half-twist being stacked together is vertically placed.
5) welding manner of employing gas shielded arc welding, carries out bottoming welding to three side seams that process groove, gage of wire 2.0mm, weldingvoltage 20V, welding current 200A, speed of welding 300mm/min, dry extension of electrode degree 25mm, protective gas CO
2, shield gas flow rate 20L/min, fusion penetration 15mm.
6) by three side seams after gas shielded arc welding bottoming welding, then adopt Lincoln weld to fill and cover welding, gage of wire 5.0mm, weldingvoltage 40V, welding current 500A, speed of welding 350mm/min, dry extension of electrode degree 30mm, fusion penetration 20mm.
7) remaining sides is sewn under condition of high vacuum degree and adopts vacuum electron beam welding, finally form 340mm composite blank.Weldingvoltage 50KV, vacuum 1 × 10
-2pa, welding current 300mA, speed of welding 150mm/min, fusion penetration 35mm.
8) adopt car type furnace to heat composite blank, total heat time is more than 12 hours, 1280 DEG C of tapping temperatures.
9) 1120 DEG C of roughing open rollings in the operation of rolling, rough rolling process strengthens every time drafts as far as possible, the thick 230mm of intermediate blank; 880 DEG C of finish rolling start rolling temperatures, the adjustment control steel plate template by drafts in the operation of rolling is good.
10) carry out slow cooling to rolling rear clad steel plate.
The 100mm hydrogenation reaction kettle barrel clad steel plate that this technique is manufactured by Combination Welding, the compound place of its carbon steel-stainless steel has obtained good fusion, as shown in Figure 1.
Embodiment 2
Produce the thick carbon steel-stainless steel hydrogenation reaction kettle barrel of 120mm clad steel plate:
1) choose respectively the continuous casting steel billet of the Q235B material that 320mm is thick and the thick 304 stainless steel billets of 40mm as raw material.
2) respectively by three lateral dominance flame cutting method finished edges of selected continuous casting steel billet and stainless steel billet, groove depth 35mm, 30 ° of bevel angles.
3) blank that completes finished edge is processed by milling machine, removed surperficial iron scale, greasy dirt etc., and two blanks are processed into same size.
4) after the blank processing is stacked together, group aligns together, and before welding, the continuous casting steel billet half-twist being stacked together is vertically placed.
5) welding manner of employing gas shielded arc welding, carries out bottoming welding to three side seams that process groove, gage of wire 1.5mm, weldingvoltage 25V, welding current 300A, speed of welding 400mm/min, dry extension of electrode degree 20mm, protective gas Ar+CO
2, shield gas flow rate 25L/min, fusion penetration 20mm.
6) by three side seams after gas shielded arc welding bottoming welding, then adopt Lincoln weld to fill and cover welding, gage of wire 6.0mm, weldingvoltage 45V, welding current 800A, speed of welding 600mm/min, dry extension of electrode degree 45mm, fusion penetration 30mm.
7) remaining sides is sewn under condition of high vacuum degree and adopts vacuum electron beam welding, finally form 360mm composite blank.Weldingvoltage 100KV, vacuum 1 × 10
-2pa, welding current 500mA, speed of welding 200mm/min, fusion penetration 50mm.
8) adopt car type furnace to heat composite blank, total heat time is more than 12 hours, 1200 DEG C of tapping temperatures.
9) 1050 DEG C of roughing open rollings in the operation of rolling, rough rolling process strengthens every time drafts as far as possible, the thick 230mm of intermediate blank; 850 DEG C of finish rolling start rolling temperatures, the adjustment control steel plate template by drafts in the operation of rolling is good.
10) carry out slow cooling to rolling rear clad steel plate.
Claims (2)
1. a manufacture method for clad steel plate for hydrogenation reaction kettle barrel, is characterized in that, comprises the following steps:
(1) taking the carbon steel blank of identical length and width size and stainless steel blank as raw material;
(2) by three limit finished edges of all carbon steel blanks and stainless steel blank plan solder side; groove depth 10-40mm; bevel angle 15-35 °; carbon steel and stainless steel blank are stacked together, and group aligns together, and half-twist is vertically placed; then adopt the welding manner of gas shielded arc welding; have the side seam on three faces of groove to carry out bottoming welding to carbon steel and stainless steel blank, then adopt Lincoln weld to fill and cover welding, finally by the side seam on residue face in vacuum higher than 1 × 10
-1under the high vacuum of Pa, carry out vacuum electron beam welding, assembly welding becomes composite blank;
Described gas shielded arc welding, its gage of wire 1.2-2.0mm, weldingvoltage 20-35V, welding current 120-400A, speed of welding 250-600mm/min, dry extension of electrode degree 15-25 mm, protective gas CO
2or Ar+CO
2, shield gas flow rate 15-25L/min, fusion penetration 5-20mm;
Described Lincoln weld, its gage of wire 4.0-6.0mm, weldingvoltage 30-45V, welding current 250-1600A, speed of welding 250-600mm/min, dry extension of electrode degree 25-45 mm, fusion penetration 10-30mm;
Described vacuum electron beam welding, its weldingvoltage 30-150KV, welding current 100-500mA, speed of welding 50-700mm/min, fusion penetration 20-50mm;
(3) the composite blank dress bogie-type furnace that butt welding connects or soaking pit heating, tapping temperature is controlled at 1160～1280 DEG C;
(4) come out of the stove after rolling, adopt two-stage rolling, 1000～1150 DEG C of first stage start rolling temperatures, 820～920 DEG C of second stage start rolling temperatures, workpiece thickness is not less than 1.4 times of finished product clad steel plate thickness;
(5) carry out slow cooling to rolling rear clad steel plate.
2. the manufacture method of clad steel plate for a kind of hydrogenation reaction kettle barrel as claimed in claim 1, is characterized in that, described step (1) carbon steel sotck thinkness is 300-600mm, and stainless steel sotck thinkness is 10-60mm.
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| CN102764960B true CN102764960B (en) | 2014-10-22 |
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| CN104209660A (en) * | 2013-05-31 | 2014-12-17 | 宝山钢铁股份有限公司 | Composite blank assembly welding groove preparation method |
| CN103302097A (en) * | 2013-06-29 | 2013-09-18 | 济钢集团有限公司 | Method for rolling carbon steel and low alloy steel large-piece-weight extra thick composite blank |
| CN104117539A (en) * | 2014-06-28 | 2014-10-29 | 济钢集团有限公司 | Composite billet manufacturing and automatic rolling technology for heavy plate mill |
| CN104708276B (en) * | 2015-02-10 | 2017-07-07 | 李向民 | A kind of preparation method of stainless steel clad plate |
| EP3533554A1 (en) * | 2015-03-26 | 2019-09-04 | Institute Of Metal Research Chinese Academy Of Sciences | Constructing and forming method for preparing homogenized forge pieces |
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| CN105728492B (en) * | 2016-03-11 | 2018-02-23 | 华中科技大学 | The clad steel plate of a kind of yield strength more than 700MPa and preparation method thereof |
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| CN113578966B (en) * | 2021-08-02 | 2023-09-19 | 沈阳科安捷材料技术有限公司 | Production process and device for low-cost high-performance stainless steel composite board roll |
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| CN101773931A (en) * | 2009-12-30 | 2010-07-14 | 东北大学 | Method for rolling special thick board by means of vacuum compositing |
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