CN117000808A - Production method of double-layer alloy composite seamless pipe - Google Patents
Production method of double-layer alloy composite seamless pipe Download PDFInfo
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- CN117000808A CN117000808A CN202310965775.1A CN202310965775A CN117000808A CN 117000808 A CN117000808 A CN 117000808A CN 202310965775 A CN202310965775 A CN 202310965775A CN 117000808 A CN117000808 A CN 117000808A
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- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 140
- 239000000956 alloy Substances 0.000 title claims abstract description 140
- 239000002131 composite material Substances 0.000 title claims abstract description 56
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 23
- 238000001125 extrusion Methods 0.000 claims abstract description 87
- 238000010438 heat treatment Methods 0.000 claims abstract description 28
- 238000005097 cold rolling Methods 0.000 claims abstract description 24
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000000463 material Substances 0.000 claims abstract description 19
- 238000003466 welding Methods 0.000 claims abstract description 19
- 230000007547 defect Effects 0.000 claims abstract description 16
- 238000003754 machining Methods 0.000 claims abstract description 14
- 238000001192 hot extrusion Methods 0.000 claims abstract description 11
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 11
- 238000009713 electroplating Methods 0.000 claims abstract description 9
- 229910001209 Low-carbon steel Inorganic materials 0.000 claims abstract description 8
- 238000012545 processing Methods 0.000 claims abstract description 8
- 238000007599 discharging Methods 0.000 claims abstract description 7
- 238000004381 surface treatment Methods 0.000 claims abstract description 5
- 238000009749 continuous casting Methods 0.000 claims abstract description 3
- 238000005242 forging Methods 0.000 claims abstract description 3
- 238000002360 preparation method Methods 0.000 claims abstract description 3
- 239000011521 glass Substances 0.000 claims description 36
- 239000000314 lubricant Substances 0.000 claims description 19
- 239000000843 powder Substances 0.000 claims description 19
- 239000011248 coating agent Substances 0.000 claims description 18
- 238000000576 coating method Methods 0.000 claims description 18
- 238000000034 method Methods 0.000 claims description 18
- 230000008569 process Effects 0.000 claims description 16
- 230000005674 electromagnetic induction Effects 0.000 claims description 12
- 238000001816 cooling Methods 0.000 claims description 10
- 238000005096 rolling process Methods 0.000 claims description 10
- 230000001050 lubricating effect Effects 0.000 claims description 9
- 238000000137 annealing Methods 0.000 claims description 8
- 230000003064 anti-oxidating effect Effects 0.000 claims description 8
- 238000000227 grinding Methods 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 claims description 4
- 238000009826 distribution Methods 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 4
- 239000000839 emulsion Substances 0.000 claims description 4
- 229910002804 graphite Inorganic materials 0.000 claims description 4
- 239000010439 graphite Substances 0.000 claims description 4
- 238000005461 lubrication Methods 0.000 claims description 4
- 230000003746 surface roughness Effects 0.000 claims description 4
- 238000005406 washing Methods 0.000 claims description 4
- 238000005498 polishing Methods 0.000 claims description 2
- 238000007789 sealing Methods 0.000 claims description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims 2
- 229910010413 TiO 2 Inorganic materials 0.000 claims 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims 2
- 229910004298 SiO 2 Inorganic materials 0.000 claims 1
- 239000000203 mixture Substances 0.000 claims 1
- 230000007797 corrosion Effects 0.000 abstract description 6
- 238000005260 corrosion Methods 0.000 abstract description 6
- 238000010008 shearing Methods 0.000 description 7
- 238000005336 cracking Methods 0.000 description 6
- 230000032798 delamination Effects 0.000 description 6
- 238000005070 sampling Methods 0.000 description 4
- 238000013329 compounding Methods 0.000 description 3
- 238000005238 degreasing Methods 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000009750 centrifugal casting Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 239000010970 precious metal Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
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- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 230000000135 prohibitive effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 238000004513 sizing Methods 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B17/00—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
- B21B17/02—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling with mandrel, i.e. the mandrel rod contacts the rolled tube over the rod length
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/02—Making uncoated products
- B21C23/04—Making uncoated products by direct extrusion
- B21C23/08—Making wire, bars, tubes
- B21C23/085—Making tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/32—Lubrication of metal being extruded or of dies, or the like, e.g. physical state of lubricant, location where lubricant is applied
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J3/00—Lubricating during forging or pressing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/06—Methods for forging, hammering, or pressing; Special equipment or accessories therefor for performing particular operations
- B21J5/08—Upsetting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/06—Methods for forging, hammering, or pressing; Special equipment or accessories therefor for performing particular operations
- B21J5/10—Piercing billets
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/12—Electroplating: Baths therefor from solutions of nickel or cobalt
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Extrusion Of Metal (AREA)
Abstract
The invention relates to a production method of a double-layer alloy composite seamless pipe. The outer layer of the double-layer alloy composite seamless pipe is made of low carbon steel, the inner layer of the double-layer alloy composite seamless pipe is made of nickel base alloy, the outer layer of alloy bar stock is a continuous casting billet or a rolled billet, and the inner layer of alloy bar stock is a forging billet. The production steps are as follows: preparing a blank; upsetting the material; machining blanks; hot reaming is performed; carrying out hot extrusion; performing heat treatment; surface treatment; cold rolling; and (3) finishing treatment. The blank preparation process comprises the following steps: calculating theory; discharging; electroplating; assembling the blank; and (5) welding the head and tail pads. The inner layer alloy and the outer layer alloy of the double-layer alloy composite seamless pipe produced by the invention are firmly combined, the defect of extrusion layering is reduced, the outer layer alloy has high strength, the inner layer alloy has good corrosion resistance, the yield processing defect is improved, and the material cost is reduced.
Description
Technical Field
The invention belongs to the technical field of industrial equipment production, and relates to a production method of a double-layer alloy composite seamless pipe.
Background
With the development of industries such as petroleum, natural gas, chemical industry and the like, the demand of pipelines is increased, higher requirements are put on the mechanical and corrosion resistance of the pipelines, the pipeline industry is required to take markets as guidance, the pipelines with moderate price and excellent performance are developed and utilized, the ever-increasing market demands are met, and meanwhile, the brand of the pipelines is built in the industry. Nickel-based alloy pipes are widely used in the corrosion-resistant field, but the high price of the pipes is prohibitive for a plurality of using units, so that double-layer alloy composite pipes are produced for reducing the cost of the pipes.
The prior manufacturing technology is as follows: the manufacturing process of the composite seamless pipe is many, and the common processes are explosion molding compounding, overlaying molding compounding, centrifugal casting extrusion molding and the like, and the common processes are all methods for compounding by adopting two alloys as raw materials.
From the angles of the composite process and deformation characteristics, all the processes can manufacture double-layer alloy composite seamless pipes. The centrifugal casting composite round tube blank and extrusion process is very suitable for manufacturing high-end composite tube products with nickel-based alloy inner layer metal, but has poor plasticity of cast structure, and is easy to delaminate and crack after extrusion, while other composite processes are only applied to the low-end field due to the defects of low bonding strength and the like.
Disclosure of Invention
The invention aims to provide a production method of a double-layer alloy composite seamless pipe, which is beneficial to the combination of alloys in the extrusion process, reduces the defects of extrusion layering, improves the strength and corrosion resistance of the seamless pipe, saves precious metals and reduces the material cost.
The technical scheme of the invention is as follows: the production method of the double-layer alloy composite seamless pipe comprises the following steps that the outer layer of the double-layer alloy composite seamless pipe is made of low carbon steel, and the inner layer of the double-layer alloy composite seamless pipe is made of nickel-based alloy:
preparing a blank: and selecting an outer layer alloy bar material and an inner layer alloy bar material which are made of the proper materials of the double-layer alloy composite seamless pipe, calculating the size, and electroplating, assembling and welding.
Upsetting the material; the double-layer alloy blank is coated with an anti-oxidation coating, heated to 100-150 ℃, and kept at the temperature for 1h for drying. Heating to 700-800 ℃ in a resistance furnace, preserving heat for 3-5 h for preheating, and heating to 1170-1220 ℃ in an electromagnetic induction heating furnace. And (3) uniformly roll-coating a glass powder lubricant on the outer surface of the furnace outlet, placing the furnace outlet into an upsetting barrel with the inner diameter being 6-12 mm larger than the outer diameter of the double-layer alloy blank, upsetting the furnace outlet, eliminating gaps between the inner layer and the outer layer of the double-layer alloy blank, and air cooling to room temperature after upsetting.
Machining blanks: the single side of the outer circle of the double-layer alloy blank after upsetting is processed by 3 mm-5 mm, and a through hole with the diameter of 35 mm-100 mm is processed in the center. The inner hole of the head pad is provided with a horn mouth, and the outer circle is provided with a round angle of R30 mm. And (3) grinding and polishing the inner and outer surfaces to remove the defects of collision, lathe tool lines and the like, wherein the surface roughness Ra is less than or equal to 3.2 mu m.
Hot reaming is performed; and placing the machined blank in a reaming barrel of a vertical reamer for hot reaming.
Hot extrusion: and placing the blanks after hot reaming into an extrusion barrel of a horizontal extruder for hot extrusion.
Performing heat treatment; heating the extruded double-layer alloy composite seamless pipe to 950-1050 ℃; preserving the heat for 0.5 to 1 hour, discharging from the furnace, and air cooling to room temperature.
Surface treatment: acid washing, grinding and removing surface glass powder, oxide skin and defects.
Cold rolling: and (3) carrying out one-pass or multi-pass cold rolling by adopting a two-roll cold rolling mill, wherein the feeding amount is 2.5-3.5 mm/time, the rolling speed is 30-50 times/min, the deformation amount of each pass is 30-50%, deoiling and annealing are carried out after each pass of cold rolling, and the annealing is carried out in a vacuum furnace or an atmosphere protection furnace.
And (3) finishing: checking, marking and bundling.
The outer layer of the double-layer alloy composite seamless pipe is made of 16Mn, 12MnV, 15MnV or 20MnV, and the inner layer is made of N06022, N10276, GH4169, N08825, N06625, N09925, N08028, N06200 or N08800. The outer layer alloy bar is a continuous casting blank or a rolled blank, and the inner layer alloy bar is a forging blank.
The blank preparation process comprises the following steps:
theoretical calculation: and (3) according to the size of the finished product of the double-layer alloy composite seamless pipe, reversely pushing to calculate the size of the inner-layer alloy bar and the outer-layer alloy bar in the distribution process of the deformation of the finished product.
Feeding: and blanking and processing the inner layer alloy bar and the outer layer alloy bar according to the length of 400-1200 mm, wherein the outer diameter of the inner layer alloy blank is 0.6-1.5 mm smaller than the inner diameter of the outer layer alloy blank, and welding grooves are processed at two ends of the inner layer alloy blank.
Electroplating: and nickel metal with the thickness of 0.1-0.3 mm is respectively electroplated on the joint surfaces of the inner alloy blank and the outer alloy blank.
And (3) assembling a blank: and (3) assembling the inner and outer alloy bars treated in the step (III) together in a vacuum chamber, and sealing and welding the two ends to form a double-layer alloy blank.
Welding the head and tail pads: and welding a head pad and a tail pad of the treated double-layer alloy blank, wherein the head pad is 120-150 mm long, the tail pad is 60-100 mm long, and the head pad and the tail pad are made of low-carbon steel.
The hot reaming step comprises: (1) the outer diameter of the blank is 10 mm-12 mm smaller than the inner diameter of the reaming barrel, and the reaming barrel is preheated to 100-200 ℃; (2) the blank is coated with an anti-oxidation coating, heated to 100 ℃ to 150 ℃ and kept for 1h, heated to 800 ℃ to 900 ℃ in a resistance furnace and kept for 3h to 5h, and heated to 1150 ℃ to 1170 ℃ in an electromagnetic induction heating furnace; (3) coating glass powder lubricants on the inner and outer surfaces before reaming of the blank, placing the blank in a reaming barrel so that one end of a bell mouth faces upwards, placing a lubricating glass bowl prepared in advance at the bell mouth, standing for 1.5-2.5 min, and placing a reaming head above the lubricating glass bowl for reaming at a reaming speed of 150-250 mm/s and a reaming ratio of 1.02-1.38.
The hot extrusion step comprises: (1) the extrusion barrel is preheated to the temperature of 250-350 ℃, the preheating temperature of the conical extrusion die and the mandrel is 300-350 ℃, the inner wall of the extrusion barrel and the surface of the mandrel are coated with graphite emulsion for lubrication, (2) before the extrusion of the blank, the blank is rapidly heated to 1170-1220 ℃ by adopting electromagnetic induction, (3) after being heated out of the furnace, the inner and outer surfaces of the blank are uniformly coated with glass powder lubricant, the blank is placed in the extrusion barrel, and a glass lubricating pad is placed at the inlet of the extrusion die. The inner diameter of the extrusion barrel is 5 mm-10 mm larger than the outer diameter of the blank after reaming, the extrusion speed is 80 mm/s-200 mm/s, the extrusion ratio is 4.0-25.0, and the double-layer alloy composite seamless pipe is air cooled to room temperature after extrusion.
The upsetting, hot reaming and hot extrusion stages were lubricated with a glass frit lubricant consisting of SiO2, al2O3, caO, mgO, tiO2, K2O, na O and B2O 3. The glass powder lubricant comprises the following components in percentage by mass: siO2:50% -70%, al2O3:1% -8%, caO:2% -12%, mgO:2% -8%, tiO2:0.1% -3%, K2O:0.2% -3%, na2O:5% -20%, B2O3:0.5 to 10 percent. According to the characteristics of the extrusion process, glass powder components with proper proportions are selected, the shape of the glass pad for extrusion is determined by the working surface of an extrusion die and the shape of the front end of a blank, the inner hole of the glass pad is 15-40 mm larger than the diameter of a pipe, and the thickness of the glass pad is 15-25 mm.
The production method of the double-layer alloy composite seamless pipe adopts electroplating to plate transition layer nickel on the joint surface in advance, the inner layer and the outer layer are firmly combined, the combination of the alloy in the extrusion process is facilitated, and the defect of extrusion layering is reduced. The outer layer alloy is low carbon steel, has high strength, the inner layer alloy is nickel base alloy, has good corrosion resistance, saves precious metals, and reduces material cost. The existence of the head and tail pads reduces extrusion force, is beneficial to the uniform flow of metal during the forming of the composite pipe, reduces processing defects and improves the yield. The seamless pipe produced by the invention has the advantages of high dimensional accuracy, good surface quality, compact internal structure, fine grains, stable mechanical property, high strength, high toughness and good corrosion resistance, and is superior to the performance of a single alloy steel pipe.
Drawings
FIG. 1 is a schematic structural view of a double-layer alloy composite billet subjected to machining after upsetting;
FIG. 2 is a schematic process flow diagram of a method of producing a double-layer alloy composite seamless tube according to the present invention;
FIG. 3 is a schematic view of a vertical reamer;
FIG. 4 is a schematic view of a horizontal extruder;
FIG. 5 is a schematic diagram of a cold rolling process;
fig. 6 is a view in the direction a of fig. 5.
Wherein: 1-head gasket, 2-blank outer layer, 3-blank inner layer, 4-tail gasket, 5-bell mouth, 6-composite blank, 7-composite seamless pipe, 8-core rod, 9-pre-rolling pipe, 10-post-rolling pipe, 11-upper roller, 12-lower roller, 17-ejection mechanism, 18-reaming barrel base, 19-shearing ring support, 20-shearing ring, 21-reaming barrel, 22-reaming rod, 23-reaming head, 24-die holder, 25-extrusion die, 26-die support, 27-extrusion barrel inner liner, 28-extrusion barrel middle layer, 29-extrusion barrel outer sleeve, 30-core rod, 31-extrusion gasket and 32-extrusion rod.
Detailed Description
The present invention will be described in detail with reference to examples and drawings. The scope of the invention is not limited to the examples, and any modifications within the scope of the claims are within the scope of the invention.
As shown in fig. 3, the vertical reamer is provided with an ejector mechanism 17, a reamer bucket base 18, a shear ring support 19, a shear ring 20, a reamer bucket 21, a reamer needle 22, and a reamer head 23. The diameter of the reaming needle is 5 mm-10 mm smaller than that of the working section of the reaming head, and the inner diameter of the shearing ring is 1 mm-2 mm larger than that of the working section of the reaming head. The reaming is not deviated by more than 1mm for the reaming barrel center line. The reaming barrel has a taper of 0.4 mm-1 mm in the length direction of the inner circle. The reaming barrel base and the reaming barrel are fixedly connected through high-strength bolts. The reaming needle is connected with the dowel bar through a threaded connector. The reaming barrel base plays a supporting role on the shearing ring support, the shearing ring support plays a supporting role on the shearing ring and the blank, the shearing ring supports the blank and cuts off the blank to expand surplus, and the dowel bar exerts reaming force on the reaming head through reaming. One end of the blank bell mouth faces upwards, and the reaming head is placed at the blank bell mouth for reaming.
As shown in fig. 4, a horizontal extruder is provided with a die holder 24, an extrusion die 25, a die support 26, an extrusion barrel inner liner 27, an extrusion barrel intermediate layer 28, an extrusion barrel outer jacket 29, a mandrel 30, an extrusion pad 31, and an extrusion rod 32. The die holder and the die support are fixed through a bottom clamping groove, the front end structure shape of the extrusion barrel is designed corresponding to the die holder structure shape, and the extrusion barrel has a taper of 0.3-1 mm in the length direction of the inner circle; the cavity of the die support is 15 mm-30 mm larger than the cavity of the extrusion die; the center line of the extrusion rod to the extrusion barrel deviates no more than 0.5mm, and the clearance between the outer circle of the extrusion pad and the inner hole of the extrusion barrel is 1.0-1.5 mm; the gap between the inner hole of the extrusion pad and the core rod is 1.5-2.5 mm, the length of the extrusion pad is 200-210 mm, the front end of the extrusion pad is a blank, the rear end of the extrusion pad is an extrusion rod, and the extrusion pad plays a role in transmitting the thrust of the extrusion rod. The extrusion die consists of an inlet transition zone, a middle sizing zone and an outlet reverse cone. When in operation, the extrusion rod, the core rod and the extrusion barrel are respectively provided with power by the hydraulic cylinder, and the extrusion barrel moves back and forth through the bottom slideway.
As shown in fig. 5, a two-roll cold rolling mill is used, which includes an upper roll 11 and a lower roll 12. The cold rolling process comprises a composite blank 6, a composite seamless pipe 7, a core rod 8, a pipe before rolling 9 and a pipe after rolling 10. Carrying out one-pass or multi-pass cold rolling, wherein the feeding amount is 2.5-3.5 mm/time, the rolling speed is 30-50 times/min, the deformation amount of each pass is 30-50%, annealing and degreasing are carried out after each pass of cold rolling, and the annealing is carried out in a vacuum furnace or an atmosphere protection furnace.
Example 1
The material of the double-layer alloy composite seamless pipe is 15MnV/N08825, the material of the outer layer is 15MnV, the material of the inner layer is N08825, the nominal specification is phi 178mm (outer diameter) x 11mm (outer layer thickness 7.5 mm+inner layer thickness 3.5 mm), the length is more than 3m, and the actual thick-wall range of the inner layer is required to be 2.5 mm-4.5 mm. The production steps are as follows:
preparing a blank: including calculating dimensions, plating, assembly, and welding.
(1) Theoretical calculation: according to the size of the finished product of the double-layer alloy composite seamless pipe, the deformation distribution process is calculated by back-pushing: double-layer alloy blank assembly phi 357mm (outer diameter)/phi 200.6mm (middle diameter), upsetting rough blank phi 363mm (outer diameter)/phi 206.6mm (middle diameter), machining blank phi 357mm (outer diameter)/phi 206.6mm (middle diameter)/phi 75mm (inner diameter), extruded tube phi 219mm (outer diameter) x 16mm (outer layer thickness 10.86 mm+inner layer thickness 5.14 mm), cold rolled tube phi 178mm (outer diameter) x 11mm (outer layer thickness 7.5 mm+inner layer thickness 3.5 mm), namely inner layer alloy bar diameter phi 200.6mm and outer layer alloy bar size diameter phi 357mm.
(2) And (3) blanking: and blanking the inner layer alloy bar and the outer layer alloy bar according to the equal length of 500mm, processing welding grooves at two ends, wherein the outer diameter of the inner layer alloy blank is 1mm smaller than the inner diameter of the outer layer alloy blank, the outer diameter of the inner layer alloy blank after processing is phi 200.1mm, and the inner diameter of the outer layer alloy blank is phi 201.1mm.
(3) Electroplating: the joint surfaces of the inner alloy blank and the outer alloy blank are respectively electroplated with a layer of nickel metal with the thickness of 0.15 mm.
(4) Blank assembly: the inner and outer alloy bars are assembled together in a vacuum chamber, and the two ends are sealed and welded to form a double-layer alloy blank, wherein the nominal specification phi 357mm (outer diameter)/phi 200.6mm (middle diameter) of the double-layer alloy blank.
(5) Welding head and tail pads: and welding a head pad and a tail pad of the double-layer alloy blank, wherein the length of the head pad is 120-150 mm, the length of the tail pad is 60-100 mm, and the head pad and the tail pad are made of low carbon steel.
Upsetting the material; firstly, coating an anti-oxidation coating on a double-layer alloy blank, heating to 100-150 ℃, preserving heat for 1h, drying, heating to 700-800 ℃ in a resistance furnace, preserving heat for 3-5 h, preheating, heating to 1170-1220 ℃ in an electromagnetic induction heating furnace, and uniformly rolling and coating a glass powder lubricant on the outer surface after discharging. Finally, the blank is put into an upsetting barrel with the inner diameter being 6mm larger than the outer diameter of the double-layer alloy blank to be upset, gaps between the inner layer and the outer layer of the double-layer alloy blank are eliminated, air cooling is carried out to room temperature after upsetting, and the specification phi 363mm (outer diameter)/phi 206.6mm (middle diameter) of the upsetting blank is achieved.
Machining blanks: and (3) machining the single side of the excircle of the upset double-layer alloy blank by 3mm, and machining a through hole with the diameter of 75mm in the center. The inner hole of the head pad is provided with a horn mouth, and the outer circle is provided with a round angle of R30 mm. The inner and outer surfaces are polished and polished, the defects of collision, lathe tool lines and the like are removed, the surface roughness Ra is less than or equal to 3.2 mu m, and the machining blank specification phi 357mm (outer diameter)/phi 206.6mm (middle diameter)/phi 75mm (inner diameter).
Hot reaming is performed; placing the blank in a reaming barrel of a vertical reamer for reaming, wherein the steps comprise: (1) the reaming barrel is preheated to the temperature of 100-200 ℃. (2) The blank is coated with anti-oxidation paint, heated to 100 ℃ to 150 ℃, kept for 1h, heated to 800 ℃ to 900 ℃ in a resistance furnace, kept for 3h to 5h, and heated to 1150 ℃ to 1170 ℃ in an electromagnetic induction heating furnace. (3) Coating glass powder lubricants on the inner and outer surfaces before reaming of the blank, placing the blank in a reaming barrel so that one end of a bell mouth faces upwards, placing a lubricating glass bowl prepared in advance at the bell mouth, and standing for 1.5-2.5 min. And then the reaming head is placed above the lubricating glass bowl for reaming, the reaming speed is 150 mm/s-250 mm/s, the diameter of the reaming head is 200mm, and the inner diameter of the reaming barrel is 369mm.
Hot extrusion: placing the blank after hot reaming in an extrusion barrel of a horizontal extruder for extrusion, wherein the steps comprise: (1) the extrusion barrel is preheated to the temperature of 250-350 ℃, the preheating temperature of the conical extrusion die and the mandrel is 300-350 ℃, and the inner wall of the extrusion barrel and the surface of the mandrel are coated with graphite emulsion for lubrication. (2) Before extrusion of the blank, electromagnetic induction is adopted to rapidly heat the blank to 1170-1220 ℃. (3) After the blank is heated and discharged out of the furnace, the inner and outer surfaces of the blank are uniformly coated with glass powder lubricant, the blank is placed into an extrusion barrel, and a glass lubricant pad is placed at the inlet of an extrusion die. The inner diameter of the extrusion barrel is 5 mm-10 mm larger than the outer diameter of the blank after reaming, the extrusion speed is 80 mm/s-200 mm/s, the inner diameter of the extrusion barrel is 375mm, the diameter of the core rod is 189.2mm, the inner diameter of the extrusion die is 223.4mm, the extruded double-layer alloy composite seamless pipe is air-cooled to room temperature, and the specification phi 219mm (outer diameter) x 16mm (outer layer thickness 10.86 mm+inner layer thickness 5.14 mm) of the extruded pipe is cooled;
performing heat treatment; heating the extruded double-layer alloy composite seamless pipe to 980 ℃ and preserving heat for 0.5-1 h, discharging from the furnace and air-cooling to room temperature.
Surface treatment: acid washing, grinding and removing surface glass powder, oxide skin and defects.
Cold rolling: the cold rolling is carried out once by adopting a two-roll cold rolling mill shown in FIG. 5, the feeding amount is 2.5-3.5 mm/time, the rolling speed is 45 times/min, the specification of a cold-rolled tube is phi 178mm (outer diameter) multiplied by 11mm (outer layer thickness 7.5 mm+inner layer thickness 3.5 mm), and the degreasing and annealing are carried out after the cold rolling.
And (3) finishing: checking, marking and bundling.
Ultrasonic flaw detection is carried out on the produced 15MnV/N08825 double-layer alloy composite seamless pipe, no layering defect is found, and sampling inspection data are shown in table 1.
TABLE 1.15 sampling test results of MnV/N08825 double-layer alloy composite seamless tubes
| Project | Binding force/MPa | Bending | Flattening | Flaring (flaring) |
| Sample 1# -1 | 325 | Qualified product | Qualified product | Qualified product |
| Sample 1# -2 | 308 | Qualified product | Qualified product | Qualified product |
| Technical index | ≥250 | No delamination and cracking | No delamination and cracking | No delamination and cracking |
Example 2
The double-layer alloy composite seamless pipe is made of 16Mn/N08800, the outer layer is made of 16Mn, the inner layer is made of N08800, the nominal specification is phi 114mm (outer diameter) multiplied by 10mm (outer layer thickness 7 mm+inner layer thickness 3 mm), the length is more than 2.5mm, and the actual thick-wall range of the inner layer is required to be 2 mm-4 mm.
The specific production steps are as follows:
preparing a blank: including calculating dimensions, plating, assembly, and welding.
(1) Theoretical calculation: according to the size of the finished product of the double-layer alloy composite seamless pipe, the deformation distribution process is calculated by back-pushing: the double-layer alloy blank assembly phi 242mm (outer diameter)/phi 133.3mm (middle diameter), upsetting rough blank phi 248mm (outer diameter)/phi 139.3mm (middle diameter), machining blank phi 242mm (outer diameter)/phi 139.3mm (middle diameter)/phi 65mm (inner diameter), extruded tube phi 161mm (outer diameter) x 18mm (outer layer thickness 12.49mm + inner layer thickness 5.51 mm), cold rolled tube phi 133mm (outer diameter) x 13mm (outer layer thickness 9.07mm + inner layer thickness 3.93 mm), cold rolled tube phi 114mm (outer diameter) x 10mm (outer layer thickness 7mm + inner layer thickness 3 mm), namely inner layer alloy bar diameter phi 133.3mm and outer layer alloy bar size diameter phi 242mm.
(2) And (3) blanking: and blanking the inner layer alloy bar and the outer layer alloy bar according to the length of 650mm, processing welding grooves at two ends, wherein the outer diameter of the inner layer alloy blank is 1.4mm smaller than the inner diameter of the outer layer alloy blank, the outer diameter of the inner layer alloy blank after processing is phi 132.6mm, and the inner diameter of the outer layer alloy blank is phi 134.0mm.
(3) Electroplating: and nickel metal with the thickness of 0.25mm is respectively electroplated on the joint surfaces of the inner alloy blank and the outer alloy blank.
(4) Blank assembly: the treated inner and outer alloy bars are assembled together in a vacuum chamber, and the two ends are sealed and welded to form a double-layer alloy blank, wherein the nominal specification phi of the double-layer alloy blank is 242mm (outer diameter)/phi 133.3mm (middle diameter).
(5) Welding head and tail pads: and welding a head pad and a tail pad of the processed double-layer alloy blank, wherein the length of the head pad is 120-150 mm, the length of the tail pad is 60-100 mm, and the head pad and the tail pad are made of low carbon steel.
Upsetting the material; firstly, coating an anti-oxidation coating on a double-layer alloy blank, heating to 100-150 ℃, preserving heat for 1h, drying, heating to 700-800 ℃ in a resistance furnace, preserving heat for 3 h-3.5 h, preheating, heating to 1170-1200 ℃ in an electromagnetic induction heating furnace, uniformly roll-coating glass powder lubricant on the outer surface after discharging, finally, upsetting in an upsetting barrel with the inner diameter being 6mm larger than the outer diameter of the double-layer alloy blank, eliminating gaps between the inner layer alloy blank and the outer layer alloy blank, air cooling to room temperature after upsetting, and upsetting blank specification phi 248mm (outer diameter)/phi 139.3mm (intermediate diameter).
Machining blanks: and (3) machining the single side of the outer circle of the double-layer alloy blank subjected to upsetting treatment by 3mm, and machining a through hole with the diameter of 65mm in the center. A horn mouth is processed at the inner hole of the head pad, and an R30mm round angle is processed at the outer circle; the inner and outer surfaces are polished and polished, the defects of collision, lathe tool lines and the like are removed, the surface roughness Ra is less than or equal to 3.2 mu m, and the machining blank specification phi 242mm (outer diameter)/phi 139.3mm (middle diameter)/phi 65mm (inner diameter).
Hot reaming is performed; placing the processed blank in a reaming barrel of a vertical reamer for reaming, wherein the steps comprise: (1) the reaming barrel is preheated to the temperature of 100-200 ℃. (2) The blank is coated with anti-oxidation paint, heated to 100 ℃ to 150 ℃ and kept for 1h, heated to 800 ℃ to 900 ℃ in a resistance furnace and kept for 3h to 5h, and heated to 1150 ℃ to 1170 ℃ in an electromagnetic induction heating furnace. (3) Coating glass powder lubricants on the inner and outer surfaces before reaming of the blank, placing the blank in a reaming barrel so that one end of a bell mouth faces upwards, placing a lubricating glass bowl prepared in advance at the bell mouth, and standing for 1.5-2.0 min. And then the reaming head is placed above the lubricating glass bowl for reaming, the reaming speed is 150 mm/s-250 mm/s, the diameter of the reaming head is 135mm, and the inner diameter of the reaming barrel is 250mm.
Hot extrusion: placing the blank after hot reaming in an extrusion barrel of a horizontal extruder for extrusion, wherein the steps comprise: (1) the extrusion barrel is preheated to the temperature of 250-350 ℃, the preheating temperature of the conical extrusion die and the mandrel is 300-350 ℃, and the inner wall of the extrusion barrel and the surface of the mandrel are coated with graphite emulsion for lubrication. (2) Before extrusion, the blank is heated to 1170-1210 ℃ rapidly by electromagnetic induction. (3) After the blank is heated and discharged out of the furnace, the inner and outer surfaces of the blank are uniformly coated with glass powder lubricant, the blank is placed into an extrusion barrel, and a glass lubricant pad is placed at the inlet of an extrusion die. The inner diameter of the extrusion barrel is 5 mm-10 mm larger than the outer diameter of the blank after reaming, the extrusion speed is 100 mm/s-200 mm/s, the inner diameter of the extrusion barrel is 255mm, the diameter of the core rod is 126mm, and the inner diameter of the extrusion die is 164mm. Air-cooling the extruded double-layer alloy composite seamless pipe to room temperature, wherein the specification phi 161mm (outer diameter) x 18mm (the thickness of the outer layer is 12.49 mm+the thickness of the inner layer is 5.51 mm) of the extruded pipe after cooling;
performing heat treatment; heating the extruded double-layer alloy composite seamless pipe to 1150 ℃, preserving heat for 0.5-1 h, discharging from the furnace, and air-cooling to room temperature.
Surface treatment: acid washing, grinding and removing surface glass powder, oxide skin and defects.
Cold rolling: the two-pass cold rolling is carried out by a two-roll cold rolling mill shown in FIG. 5, the feeding amount is 2.5-3.5 mm/time, and the rolling speed is 45 times/min. The first cold rolling specification was phi 133mm (outer diameter) x 13mm (outer layer thickness 9.07mm + inner layer thickness 3.93 mm). The second-pass cold rolling specification is phi 114mm (outer diameter) multiplied by 10mm (outer layer thickness 7 mm+inner layer thickness 3 mm), and degreasing and annealing are carried out after each cold rolling.
And (3) finishing: checking, marking and bundling.
Ultrasonic flaw detection is carried out on the produced 16Mn/N08800 double-layer alloy composite seamless pipe, no layering defect is found, and sampling inspection data are shown in Table 2.
TABLE 2.16 sampling test results of Mn/N08800 double-layer alloy composite seamless pipe
| Project | Binding force/MPa | Bending | Flattening | Flaring (flaring) |
| Sample 2# -1 | 265 | Qualified product | Qualified product | Qualified product |
| Sample 2# -2 | 278 | Qualified product | Qualified product | Qualified product |
| Technical index | ≥210 | No delamination and cracking | No delamination and cracking | No delamination and cracking |
Claims (7)
1. A production method of a double-layer alloy composite seamless pipe is characterized by comprising the following steps: the outer layer material of the double-layer alloy composite seamless pipe is low carbon steel, the inner layer material is nickel-based alloy, and the production method comprises the following steps:
preparing a blank: selecting an outer layer alloy bar material and an inner layer alloy bar material which are made of a proper material of the double-layer alloy composite seamless pipe, calculating the size, and electroplating, assembling and welding;
upsetting the material; coating an anti-oxidation coating on the double-layer alloy blank, heating to 100-150 ℃, and preserving heat for 1h for drying; heating to 700-800 ℃ in a resistance furnace, preserving heat for 3-5 h for preheating, and heating to 1170-1220 ℃ in an electromagnetic induction heating furnace; uniformly roll-coating glass powder lubricant on the outer surface of the furnace outlet, placing the furnace outlet into an upsetting barrel with the inner diameter 6-12 mm larger than the outer diameter of the double-layer alloy blank for upsetting, and air-cooling to room temperature after upsetting;
machining blanks: the single side of the outer circle of the double-layer alloy blank after upsetting is processed by 3 mm-5 mm, and a through hole with the diameter of 35 mm-100 mm is processed in the center; a horn mouth is processed at the inner hole of the head pad, and an R30mm round angle is processed at the outer circle; grinding and polishing the inner and outer surfaces to remove the defects of collision, lathe tool lines and the like, wherein the surface roughness Ra is less than or equal to 3.2 mu m;
hot reaming is performed; placing the machined blank into a reaming barrel of a vertical reamer for hot reaming;
hot extrusion: and placing the blanks after hot reaming into an extrusion barrel of a horizontal extruder for hot extrusion.
Performing heat treatment; heating the extruded double-layer alloy composite seamless pipe to 950-1050 ℃, preserving heat for 0.5-1 h, discharging from a furnace, and air-cooling to room temperature;
surface treatment: acid washing, grinding and removing surface glass powder, oxide skin and defects;
cold rolling: cold rolling with a two-roller cold rolling mill for one or more times, wherein the feeding amount is 2.5-3.5 mm/time, the rolling speed is 30-50 times/min, the deformation amount of each time is 30-50%, deoiling and annealing are carried out after each time of cold rolling, and the annealing is carried out in a vacuum furnace or an atmosphere protection furnace;
and (3) finishing: checking, marking and bundling.
2. The method for producing the double-layer alloy composite seamless pipe according to claim 1, which is characterized in that: the outer layer of the double-layer alloy composite seamless pipe is made of 16Mn, 12MnV, 15MnV or 20MnV, and the inner layer is made of N06022, N10276, GH4169, N08825, N06625, N09925, N08028, N06200 or N08800.
3. The production method of the double-layer alloy composite seamless pipe according to claim 1 or 2, characterized by comprising the following steps: the outer layer alloy bar is a continuous casting blank or a rolled blank, and the inner layer alloy bar is a forging blank.
4. The method for producing the double-layer alloy composite seamless pipe according to claim 1, which is characterized in that: the blank preparation process comprises the following steps:
theoretical calculation: according to the size of the finished product of the double-layer alloy composite seamless pipe, reversely pushing to calculate the size of the inner-layer alloy bar and the outer-layer alloy bar in the distribution process of the deformation of the finished product;
feeding: blanking and processing the inner layer alloy bar and the outer layer alloy bar according to the length of 400 mm-1200 mm, wherein the outer diameter of the inner layer alloy blank is 0.6 mm-1.5 mm smaller than the inner diameter of the outer layer alloy blank, and welding grooves are processed at two ends;
electroplating: respectively electroplating a layer of nickel metal with the thickness of 0.1-0.3 mm on the joint surface of the inner alloy blank and the outer alloy blank;
and (3) assembling a blank: assembling the inner and outer alloy bars treated in the step III together in a vacuum chamber, and sealing and welding the two ends to form a double-layer alloy blank;
welding the head and tail pads: and welding a head pad and a tail pad of the treated double-layer alloy blank, wherein the head pad is 120-150 mm long, the tail pad is 60-100 mm long, and the head pad and the tail pad are made of low-carbon steel.
5. The method for producing the double-layer alloy composite seamless pipe according to claim 1, which is characterized in that: the hot reaming step includes: (1) the outer diameter of the blank is 10 mm-12 mm smaller than the inner diameter of the reaming barrel, and the reaming barrel is preheated to 100-200 ℃; (2) the blank is coated with an anti-oxidation coating, heated to 100 ℃ to 150 ℃ and kept for 1h, heated to 800 ℃ to 900 ℃ in a resistance furnace and kept for 3h to 5h, and heated to 1150 ℃ to 1170 ℃ in an electromagnetic induction heating furnace; (3) coating glass powder lubricants on the inner and outer surfaces before reaming of the blank, placing the blank in a reaming barrel so that one end of a bell mouth faces upwards, placing a lubricating glass bowl prepared in advance at the bell mouth, standing for 1.5-2.5 min, and placing a reaming head above the lubricating glass bowl for reaming at a reaming speed of 150-250 mm/s and a reaming ratio of 1.02-1.38.
6. The method for producing the double-layer alloy composite seamless pipe according to claim 1, which is characterized in that: the hot extrusion step includes: (1) preheating the extrusion barrel to the temperature of 250-350 ℃, and coating graphite emulsion on the inner wall of the extrusion barrel and the surface of the core rod for lubrication, wherein the preheating temperature of the conical extrusion die and the core rod is 300-350 ℃; (2) before the blank is extruded, electromagnetic induction is adopted to rapidly heat the blank to 1170-1220 ℃; (3) after the blank is heated and discharged out of the furnace, the inner and outer surfaces of the blank are uniformly coated with glass powder lubricant, the blank is placed into an extrusion barrel, and a glass lubricant pad is placed at the inlet of an extrusion die; the inner diameter of the extrusion barrel is 5 mm-10 mm larger than the outer diameter of the blank after reaming, the extrusion speed is 80 mm/s-200 mm/s, the extrusion ratio is 4.0-25.0, and the double-layer alloy composite seamless pipe is air cooled to room temperature after extrusion.
7. The method for producing the double-layer alloy composite seamless pipe according to claim 1, characterized by comprising the following steps: the upsetting, hot reaming and hot extrusion stages are lubricated with a glass frit lubricant consisting of SiO 2 、Al 2 O 3 、CaO、MgO、TiO 2 、K 2 O、Na 2 O and B 2 O 3 Composition; the glass powder lubricant comprises the following components in percentage by mass: siO (SiO) 2 ：50％～70％、Al 2 O 3 ：1％～8％、CaO：2％～12％、MgO：2％～8％、TiO 2 ：0.1％～3％、K 2 O：0.2％～3％、Na 2 O：5％～20％、B 2 O 3 ：0.5％～10％。
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