CN103045837B - Manufacturing method of duplex-phase stainless seamless tube - Google Patents
Manufacturing method of duplex-phase stainless seamless tube Download PDFInfo
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- CN103045837B CN103045837B CN201310010343.1A CN201310010343A CN103045837B CN 103045837 B CN103045837 B CN 103045837B CN 201310010343 A CN201310010343 A CN 201310010343A CN 103045837 B CN103045837 B CN 103045837B
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Abstract
The invention relates to a manufacturing method of a duplex-phase stainless seamless tube, and the method comprises cold-drawing and heat treatment. The manufacturing method of the duplex-phase stainless seamless tube is characterized in that the diameter-to-wall ratio of the manufactured duplex-phase stainless seamless tube is 3-5, and reduction of a hot-extrusion cross section is not lower than 60%; the cold-drawing is performed for 3-5 passes, and the reduction of cross section of each pass is not greater than 20%; and the heat treatment annealing is performed once after each pass of cold-drawing. The performance of the seamless tube manufactured by the manufacturing method of the duplex-phase stainless seamless tube can meet standard requirements of GB/T21833-2008 and ASMESA789/790M.
Description
Technical field
The present invention relates to a kind of manufacture method of seamless two-phase stainless-steel pipe, is specifically the manufacture method of the seamless two-phase stainless-steel pipe of diameter-wall-rate 3 ~ 5.
Background technology
The ratio of outer diameter of steel pipes and wall thickness is called diameter-wall-rate, usual diameter-wall-rate be about 10 seamless two-phase stainless-steel pipe technique simple, production difficulty is little, and common stainless steel seamless steel tubing mill all can produce.For the seamless tube of diameter-wall-rate 3 ~ 5, hot and cold processing all can exceed the ability category of production unit, production difficulty is very large, adopt the manufacture method of existing seamless two-phase stainless-steel pipe cannot meet product requirement at all, therefore, the seamless two-phase stainless-steel pipe of current diameter-wall-rate 3 ~ 5 there is no production technique.
In addition, duplex stainless steel has austenite and ferrite two and the tissue deposited, and thermoplasticity is poor, and under high temperature, austenite is different with ferritic deformation mechanism, and stress and strain distribution uneven during hot-work easily causes crackle to be expanded in phase boundary.Meanwhile, the mechanical property of duplex stainless steel is more than 2 times of austenitic stainless steel, surrender and tensile strength high, unit elongation is lower, and cold-forming property is poor.Therefore, there is no case in the producing country for diameter-wall-rate 3 ~ 5 seamless two-phase stainless-steel pipe.
Summary of the invention
In order to overcome the above-mentioned deficiency of the manufacture method of existing seamless two-phase stainless-steel pipe, a kind of manufacture method of seamless two-phase stainless-steel pipe of diameter-wall-rate 3 ~ 5 is provided, meets the standard-required of GB/T21833-2008 and ASMESA789/790M by the performance of the seamless two-phase stainless-steel pipe of manufacture of the present invention.
Aim of the present invention is for diameter-wall-rate 3 ~ 5 duplex phase stainless tube hot and cold deformation technique of trimmed size rational and device parameter, because the cold hardening effect of duplex stainless steel is large, therefore cold working have employed the cold-drawing technology of gross distortion hot extrusion+small deformation multi-pass.
The manufacture method of this seamless two-phase stainless-steel pipe comprises cold-drawn and thermal treatment, it is characterized in that: the diameter-wall-rate of the seamless two-phase stainless-steel pipe manufactured by it is 3 ~ 5, and the relative reduction in area of hot extrusion is not less than 60%; The cold-drawn of multi-pass (3 ~ 5 passage), every time relative reduction in area is not more than 20%; A heat-treatment of annealing is all carried out after every time cold-drawn.
Say in detail, the manufacture method of this seamless two-phase stainless-steel pipe comprises following step successively:
ihot extrusion
Blank prepares to adopt Φ 219 ~ Φ 247mm forging blank, depth drill processing Φ 40 ~ Φ 60mm central through hole;
The preheating in ring furnace of blank preheated charge, ring furnace temperature arranges 700 ± 10 DEG C, the 3h ± 5min of time in stove;
Medium-frequency induction furnace induction heating put into by induction heating blank, induction heating target temperature 1180 ± 10 DEG C, soaking time 1 ~ 3min, heating power 600 ~ 650KW, insulation power ≯ 200KW.
Extruding extruding adopts the extruding tool and mould of Φ 78 × 16 ~ Φ 140 × 40mm, and relative reduction in area is not less than 60%, completes solid solution after extruding in 30 ± 5s.
After extruding, the outside dimension of steel pipe is 78 ~ 140mm, and wall thickness is 16 ~ 40mm.Again successively through aligning, pickling, reconditioning, lubrication.
iIcold-drawn
First passage: Φ 78 ~ Φ 140mm is drawn to Φ 71 ~ Φ 133mm
,process control relative reduction in area is not more than 20%;
Steel pipe after first passage cold-drawn, heat-treats after degreasing.
iIIthermal treatment
Steel pipe after first passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1080 ± 10 DEG C, and soaking time is not less than 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.
. through aligning, pickling, reconditioning, lubrication, then the second passage cold-drawn.
iVcold-drawn
Second passage: Φ 71 ~ Φ 133mm is drawn to Φ 64 ~ Φ 126mm, and process control relative reduction in area is not more than 20%;
Steel pipe after second passage cold-drawn, heat-treats after degreasing.
vthermal treatment
Steel pipe after second passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1080 ± 10 DEG C, and soaking time is not less than 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.
Carry out after thermal treatment aligning, pickling, reconditioning, lubrication, then the 3rd passage cold-drawn.
vIcold-drawn
3rd passage: Φ 64 ~ Φ 126mm is drawn to Φ 57 ~ Φ 119mm, and process control relative reduction in area is not more than 20%;
Steel pipe after 3rd passage cold-drawn, heat-treats after degreasing.
Ⅻthermal treatment
Steel pipe after 3rd passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1060 ± 10 DEG C, and soaking time is not less than 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.Steel pipe after 3rd passage cold-drawn postheat treatment, carries out aligning, pickling is finished product.
Remarks: based on contract (or user) technical need, can carry out the corresponding increase of passage.
Could put in storage through inspection, flaw detection.
The present invention efficiently solves the problem of the cold and hot working distortion difficulty of diameter-wall-rate 3 ~ 5 seamless two-phase stainless-steel pipe, gross distortion hot extrusion process relative reduction in area reaches more than 60%; cold working relative reduction in area ≯ 20% of small deformation, ensure that specification and the physicochemical property of production tube.
The pipe undoubtedly of the manufacture method manufacture of seamless two-phase stainless-steel pipe of the present invention, performance meets the standard-required of GB/T21833-2008 and ASMESA789/790M.
Embodiment
Describe the specific embodiment of the present invention in detail below in conjunction with embodiment, but the specific embodiment of the present invention is not limited to following embodiment.
Embodiment
The present embodiment manufacture be diameter-wall-rate ≯ 5 seamless two-phase stainless-steel pipes, require as follows:
Material: S32205;
Specification: Φ 57 × 16.5mm;
Technical requirements: acid wash passivation
Take following technique:
Φ 219/50(extrudes) → 78 × 18(cold-drawn) → 71 × 17.5 (cold-drawn) → 65 × 17 (cold-drawn) → 57 × 16.5
The manufacture method of this seamless two-phase stainless-steel pipe comprises following step successively:
ihot extrusion
1 blank prepares to adopt Φ 219mm forging blank, depth drill processing Φ 40mm central through hole;
2 blank preheated charge preheatings in ring furnace, ring furnace temperature arranges 700 DEG C, the 3h of time in stove;
Medium-frequency induction furnace induction heating put into by 3 induction heating blanks, induction heating target temperature 1180 DEG C, soaking time 1min, heating power 600KW, insulation power 180KW.
4 extruding extruding adopt the extruding tool and mould of Φ 78 × 18mm, and relative reduction in area is 91.6%, completes solid solution after extruding in 30s.
After 5 extruding, the outside dimension of steel pipe is 77.2 ~ 77.4mm, and wall thickness is 17.8 ~ 18.0mm.Again successively through aligning, pickling, reconditioning, lubrication.
iIcold-drawn
First passage: Φ 78 × 18mm is drawn to Φ 71 × 17.5mm operation;
After cold-drawn, outer diameter of steel pipes is of a size of 71.1 ~ 71.2mm, and wall thickness is 17.3 ~ 17.5mm;
Steel pipe after first passage cold-drawn, heat-treats after degreasing.
iIIthermal treatment
Steel pipe after first passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1080 DEG C, soaking time 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.
. through aligning, pickling, reconditioning, lubrication, then the second passage cold-drawn.
iVcold-drawn
Second passage: Φ 71 × 17.5mm is drawn to Φ 65 × 17mm operation;
After cold-drawn, outer diameter of steel pipes is of a size of 65.0 ~ 65.1mm, and wall thickness is 16.8 ~ 17.0mm;
Steel pipe after the second passage cold-drawn, heat-treats after degreasing.
vthermal treatment
Steel pipe after second passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1080 DEG C, soaking time 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.
Carry out after thermal treatment aligning, pickling, reconditioning, lubrication, then the 3rd passage cold-drawn.
vIcold-drawn
3rd passage: Φ 65 × 17mm is drawn to Φ 57 × 16.5mm operation;
After cold-drawn, outer diameter of steel pipes is of a size of 57.0 ~ 57.1mm, and wall thickness is 16.4 ~ 16.6mm;
Steel pipe after the 3rd passage cold-drawn, heat-treats after degreasing.
Ⅻthermal treatment
Steel pipe after 3rd passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1060 DEG C, soaking time 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.Steel pipe after 3rd passage cold-drawn postheat treatment, carries out aligning, pickling is finished product.
Could put in storage through inspection, flaw detection.
The uniform wall thickness of steel pipe, physicochemical property is qualified, meets service requirements.Select three passage cold-drawns, resistance to deformation is little, Cold Drawing Process without scuffing, excellent surface quality.
The seamless two-phase stainless-steel pipe that the present embodiment manufactures, mechanical property meets GB/T21833-2008 " austenite-ferrite two-phase stainless steel seamless steel tube " and ASMESA789/790M " austenite-ferrite duplex stainless steel is seamless and Welded Steel Pipe " standard-required.The various technical parameters of the present embodiment see the following form:
Physicochemical property
Claims (2)
1. the manufacture method of a seamless two-phase stainless-steel pipe, it comprises cold-drawn and thermal treatment, it is characterized in that: the diameter-wall-rate of the seamless two-phase stainless-steel pipe manufactured by it is 3 ~ 5, adopt Φ 219 ~ Φ 247mm forging blank, depth drill processing Φ 40 ~ Φ 60mm central through hole; Carry out hot extrusion, the relative reduction in area of hot extrusion is not less than 60%; Adopt the cold-drawn of 3 ~ 5 passages, every time relative reduction in area is not more than 20%; A heat-treatment of annealing is all carried out after every time cold-drawn.
2. the manufacture method of seamless two-phase stainless-steel pipe according to claim 1, its steps characteristic is:
ihot extrusion
Blank prepares to adopt Φ 219 ~ Φ 247mm forging blank, depth drill processing Φ 40 ~ Φ 60mm central through hole;
The preheating in ring furnace of blank preheated charge, ring furnace temperature arranges 700 ± 10 DEG C, the 3h ± 5min of time in stove;
Medium-frequency induction furnace induction heating put into by induction heating blank, induction heating target temperature 1180 ± 10 DEG C, soaking time 1 ~ 3min;
Extruding extruding adopts the extruding tool and mould of Φ 78 × 16 ~ Φ 140 × 40mm, and relative reduction in area is not less than 60%, completes solid solution after extruding in 30 ± 5s;
After extruding, the outside dimension of steel pipe is 78 ~ 140mm, and wall thickness is 16 ~ 40mm; Again successively through aligning, pickling, reconditioning, lubrication;
iIcold-drawn
First passage: Φ 78 ~ Φ 140mm is drawn to Φ 71 ~ Φ 133mm
,process control relative reduction in area is not more than 20%;
Steel pipe after first passage cold-drawn, heat-treats after degreasing;
iIIthermal treatment
Steel pipe after first passage cold-drawn after degreasing, load thermal treatment in continuous roller bottom type annealing furnace, target temperature 1080 ± 10 DEG C, soaking time is not less than 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s; . through aligning, pickling, reconditioning, lubrication, then the second passage cold-drawn;
iVcold-drawn
Second passage: Φ 71 ~ Φ 133mm is drawn to Φ 64 ~ Φ 126mm, and process control relative reduction in area is not more than 20%;
Steel pipe after second passage cold-drawn, heat-treats after degreasing;
vthermal treatment
Steel pipe after second passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1080 ± 10 DEG C, and soaking time is not less than 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s; Carry out after thermal treatment aligning, pickling, reconditioning, lubrication, then the 3rd passage cold-drawn;
vIcold-drawn
3rd passage: Φ 64 ~ Φ 126mm is drawn to Φ 57 ~ Φ 119mm, and process control relative reduction in area is not more than 20%;
Steel pipe after 3rd passage cold-drawn, heat-treats after degreasing;
Ⅻthermal treatment
Steel pipe after 3rd passage cold-drawn, loads thermal treatment in continuous roller bottom type annealing furnace after degreasing, target temperature 1060 ± 10 DEG C, and soaking time is not less than 3min/mm; Be incubated the solid solution of laggard horizontal high voltage Water spray, ensured that cold-zone speed is not less than 25 DEG C/s.
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