CN104646449A - Manufacturing method for cold drawn welded pipe used for hydraulic oil cylinders - Google Patents

Manufacturing method for cold drawn welded pipe used for hydraulic oil cylinders Download PDF

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Publication number
CN104646449A
CN104646449A CN201310596957.2A CN201310596957A CN104646449A CN 104646449 A CN104646449 A CN 104646449A CN 201310596957 A CN201310596957 A CN 201310596957A CN 104646449 A CN104646449 A CN 104646449A
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Prior art keywords
welded tube
tube
cold
drawn
welding
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CN201310596957.2A
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Chinese (zh)
Inventor
许卫东
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WUXI DAJIN HIGH-PRECISION COLD-DRAWN STEEL TUBE Co Ltd
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WUXI DAJIN HIGH-PRECISION COLD-DRAWN STEEL TUBE Co Ltd
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Priority to CN201310596957.2A priority Critical patent/CN104646449A/en
Publication of CN104646449A publication Critical patent/CN104646449A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21CMANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06Manufacture 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
    • B21C37/08Making tubes with welded or soldered seams
    • B21C37/0807Tube treating or manipulating combined with, or specially adapted for use in connection with tube making machines, e.g. drawing-off devices, cutting-off
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21CMANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06Manufacture 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
    • B21C37/08Making tubes with welded or soldered seams
    • B21C37/0807Tube treating or manipulating combined with, or specially adapted for use in connection with tube making machines, e.g. drawing-off devices, cutting-off
    • B21C37/0811Tube treating or manipulating combined with, or specially adapted for use in connection with tube making machines, e.g. drawing-off devices, cutting-off removing or treating the weld bead
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21CMANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06Manufacture 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
    • B21C37/30Finishing tubes, e.g. sizing, burnishing

Abstract

The invention relates to a manufacturing method for a cold drawn welded pipe used for hydraulic oil cylinders. The manufacturing method includes the steps of: longitudinal shearing, roll bending formation, high-frequency welding, weld joint treatment, sizing, online eddy current flow detection, stress relief annealing, pre-straightening treatment, pipe cutting, normalizing air cooling treatment, pinching, pickling treatment, phosphating treatment, saponification treatment, cold-drawing, induction furnace quenching treatment, box type furnace tempering treatment, straightening treatment, fine boring rolling, magnetic leakage flaw detection, and pipe cutting measurement. The product obtained by the method provided by the invention has the advantages of high yield strength, high tensile strength, precise size, smooth surface, fast machine shaping speed, high yield, and remarkably improved manufacturing precision. The cold drawn welded pipe has good surface smoothness and low roughness, the follow-up gold processing amount is reduced, the steel utilization is improved, the manufacturing cost is lowered, and energy saving and environmental protection are promoted.

Description

A kind of manufacture method of hydraulic jack cold drawing welded tube
Technical field
The invention belongs to steel pipe preparing technical field, be specifically related to a kind of manufacture method of hydraulic jack cold drawing welded tube.
Background technology
In prior art, the production technology of cylinder body of hydraulic oil cylinder, generally with hot rolled seamless steel tube, the Cutting Process of bore hole one roll extrusion associating is adopted to produce, because one of seamless steel pipe maximum defect is that wall unevenness is even, its producing cause is mainly that heating of pipe blank is uneven, rolled by piercing mill line does not correct that the Centering Roll caused is unstable, top wearing and tearing, top metapore are eccentric, pipe internal point not just, the many reasons such as pipe flexibility is excessive, need the technical difficulty removing above-mentioned whole reason one by one larger, therefore, the yield rate of seamless steel pipe is relatively low; Seamless steel pipe also easily produce infolding, in scab, stick up skin, interior straight way, interior bulge, draw the defects such as recessed, this just causes becoming in the process of oil cylinder in following process, need to carry out machining, a large amount of metals is cut into chip and wastes, and also consumes mass energy simultaneously; The blank of seamless steel pipe is that continuous casting forms, and easily there are sand holes, therefore, easily causes steel pipe parent defect.Have again, non-metallic inclusion (mainly sulfide and the oxide of steel inside, also have silicate) be easily pressed into thin slice, there is lamination, the performance of steel through-thickness tension is deteriorated significantly, in addition, the precision of seamless steel pipe is difficult to control, there will be certain minus tolerance after the cooling period, this minus tolerance hem width is wider, the thicker performance of thickness more obvious.So all cannot require too accurate for the hem width of seamless steel pipe, thickness, length, angle and sideline.Adopt this kind of method to manufacture the cylinder body of hydraulic jack, speed of production is slow, energy waste is large, using rate of metal is low, yield rate is also low.
In prior art, process for producing welded pipe is the production technology of relative maturity, but, welded tube generally can not be used as the cylinder body manufacture of hydraulic jack, mainly contain some problem following and limit its application on hydraulic jack manufactures: 1), the precision of welded tube itself is relatively low, and its circularity is difficult to obtain Reliable guarantee; 2), welded tube weld time, its surface weld be easy to process, but the weld seam of inwall be difficult to process, especially on continual tinuous production, if do not processed the weld seam of its inwall, and being directly used in the man-hour that adds of oil cylinder, there is the problem that cutting output is large equally; 3), weld seam without heat treatment, cause internal stress large, be easy in using occur cracking phenomena; 4) even if weld seam is through Overheating Treatment, because welded tube is without drawing, the bearing capacity on its axial direction is relatively low, for improving its bearing capacity, needing to amplify, causing the waste of metal material.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, a kind of manufacture method of hydraulic jack cold drawing welded tube is provided, the hydraulic jack cold drawing welded tube that the method obtains, yield strength is high, tensile strength is high, precision size, smooth surface, improve the production efficiency of hydraulic jack cold drawing welded tube simultaneously, reduce manufacturing cost, propulsion energy-saving environmental protection.
According to technical scheme provided by the invention, a kind of manufacture method of hydraulic jack cold drawing welded tube comprises the steps:
(1), slitting: be that the wide coil of strip of 27SiMn carries out slitting, according to the width of coil of strip after the diameter determination slitting of welded tube on slitter by material;
(2), roll bending formation: the coil of strip after slitting is placed on exhibition bin, by feed mechanism, the termination of coil of strip is extracted out, send in continuous pressure roller shaping mechanism and carry out roll bending formation processing, described pressure roller shaping mechanism comprises continuous print many groups pressure roller pair, often organize pressure roller to two pressure rollers comprising misfortune conjunction mutually, gap is left between described two pressure rollers, the gap of adjacent pressure roller to correspondence is out of shape gradually, make the coil of strip through respective clearance become curved surface by plane, then become conglobate body by curved surface;
(3), the coil of strip of high-frequency welding: Cheng Yuanhou adopts high-frequency welding, and the vertical masonry joint docked its side carries out induction welding, forms welded tube;
(4), weld seam process: when welded tube not yet cools, adopt the weld seam of burring knife milling downhand welding pipe, described burring knife comprises and is arranged on removing outer deburring cutter and being arranged on outside welded tube and removes internal hair bayonet inside welded tube, go internal hair bayonet axially to insert in body from the opening part not yet becoming conglobate body, and reach the front of welding position; Because roll bending formation and welding are carried out continuously, the weld seam of inner wall of welded pipe is made to be treated as a difficult problem, welded tube before cutting, its length can continue tens meters on a production line, after welding fabrication, conventional means is utilized to be to cut the weld seam of inwall or to polish process, the present invention adopts and is axially inserted in body by the body open going internal hair bayonet from Cheng Yuanqian, cross high-frequency welding position, again deburring is carried out to the weld seam in pipe, make inner wall of welded pipe smooth, for follow-up cold-drawn provides guarantee; In addition, deburring carries out in time after tube-welding, and now welded tube not yet cools, and can reduce difficulty of processing, improves deburring speed;
(5), sizing: the welded tube formed after weld seam process is again through sizing mill sizing, and form steel pipe, temperature during sizing controls at 750 ~ 800 DEG C;
(6), online eddy current inspection: pop one's head in and to move in metal surface, when running into defect or the change such as material, size, make eddy current magnetism different to the reaction of coil, cause coil impedance to change, measure this variable quantity by eddy detecting instrument and just can differentiate that there are zero defect or other change in physical in metal surface;
(7), stress relief annealing: welded tube introduced heating in heating furnace and be incubated, come out of the stove with after stove cooling, obtain welded tube of annealing, object is the intensity guaranteeing welded tube, when annealing temperature is too high, processing strain recovers, the effect of work hardening can not be obtained, annealing temperature is 950 ~ 980 DEG C, the effect of work hardening can be obtained, this annealing in process is the annealing in process of entire body, ensure welding region and neighboring area consistent with all the other regions of welded tube in metallographic structure and mechanical performance, in order to remove the strength variance of welded tube, in the stove of welded tube, the retention time is 60 ~ 90 minutes,
(8), pre-straightening process: straightening temperature 600 ~ 650 DEG C, to reduce residual stress;
(9), Pipe Cutting: the welded tube feeding turned off in synchronization device through pre-straightening process cuts off, and turned off in synchronization device overall rectilinear motion of following welded tube in cutting-off process is synchronized with the movement, and when both move at the uniform velocity, is cut off by welded tube; The program adopts the method for synchronization to be cut off by welding pipe fixed length, ensure that welding, roll bending formation, weld seam process are carried out continuously in non-stop-machine situation, can improve speed of production;
(10), the process of normalizing air cooling: the Technology for Heating Processing adopting tempering again after quenching, hardening heat is 600 ~ 650 DEG C, and hardening media is water, and temperature, at 500 ~ 550 DEG C, reduces the residual stress of steel pipe;
(11), pinching: the welded tube after annealing carries out pinching process, make welded tube termination diametric shrinkage after extrusion die extruding, described extrusion die comprises the active section that two sections of diameters do not wait, seamlessly transit between two sections of active sections, welded tube termination enters from bigger diameter end and extrudes, the termination of extrusion die and welded tube is carrying out extruding front lubricant sprayer, with avoid extrude time wearing and tearing and surface tear, after the extrusion die extruding that 1 ~ 3 diameter reduces gradually, the external diameter of welded tube termination is punctured into 50 ~ 75% of original diameter;
(12), pickling processes: welded tube is carried out pickling, removes the scale on surface, concentration of hydrochloric acid: 7 ~ 19%, pickling time: 35 ~ 60 minutes, then neutralization pond rolling, rolling number of times: 2 ~ 3 times, neutralizer pH value: 9 ~ 10, then through clear water reserviors rolling, rolling number of times: 2 ~ 3 times;
(13), phosphorating treatment: the chemistry forming trbasic zinc phosphate on the surface of welded tube generates overlay film, trbasic zinc phosphate concentration: 20 ~ 30%, Phosphating Solution temperature: 68 ~ 75 DEG C, phosphating time: 10 ~ 20 minutes, Phosphating Solution free acidity: 4 ~ 7, General Acidity in Phosphating Solution: 45 ~ 75;
(14), saponification process: form the lubricating film coateds such as metallic soap on overlay film, for follow-up cold-drawn is ready, drawn tube surface can be made brighter and cleaner, saponification temperature: 55 ~ 75 DEG C, saponification time: 8 ~ 15 minutes, saponification liquor pH value: 8 ~ 9;
(15), cold-drawn: will treat that cold drawing welded tube carries out cold-drawn processing, obtain drawn tube, cold-drawing technology, mould chock plug and bore spacing: 3 ~ 5mm, pull out machine draft: 300 ~ 400t, cold-drawn speed: 5 ~ 30m/min, opening speed: 10 ~ 50m/min, drawn tube length: maximum 20m, drawn tube external diameter: 85 ~ 250mm, drawn tube wall thickness: 3 ~ 20mm;
(16), induction furnace Quenching Treatment: induction furnace hardening heat is 500 ~ 550 DEG C, and hardening media is water, reduces the residual stress of steel pipe;
(17), temper in batch-type furnace: the temperature of tempering air cooling is 350 ~ 380 DEG C, to reduce residual stress;
(18), straightening processing: be incubated 30 ~ 45 minutes in low-temp temper furnace, then carry out thermal straightening process, thermal straightening temperature 400 ~ 500 DEG C, to reduce residual stress;
(19), finish-boring rolling: pass through roll forming, rolling surface forms one deck flow harden layer, decrease elasticity and the plastic deformation of the secondary contact surface of grinding, thus improve the wearability on polished rod surface, case hardness and intensity improve, and improve the wearability of surface of the work, corrosion resistance and conformability;
(20), magnetic leakage detection: under suitable lift-off gap, inspection speed and the intensity of magnetization, to steel pipe vertical, horizontal defects detection;
(21), Pipe Cutting is measured: carry out fixed length cutting to steel pipe, after cutting, pipe is smooth.
Compared with prior art, beneficial effect of the present invention is:
1), machine-shaping speed is fast, output is high, and not injured surface during cold-drawn, can make the pipe fitting of multiple different size, process needs to adapt to client, wall thickness from 1 ~ 16mm, caliber 10 ~ 254mm; The product of size not within the scope of hot finished steel pipe standardized product can be obtained;
2), the accuracy of manufacture significantly improves, and after cold-drawn, welded tube external diameter and internal diameter precision all can be guaranteed, and eccentricity is 3% to the maximum, are less than the eccentricity of seamless steel pipe 7.5%, and its dimensional accuracy reaches H10 ~ H8;
3), when having identical chemical composition product, obtain higher mechanical performance, cold-drawn can make welded tube radial-axial direction produces plastic deformation, thus improve the yield point of steel, mechanical strength is balanced everywhere on radial-axial direction to make welded tube, bearing capacity is improved 60%, has the percentage elongation that high tensile strength is become reconciled;
4) the surface of welded pipe fineness, after cold-drawn is good, and roughness is low;
5), decrease follow-up metalworking amount, improve the utilization rate of steel, reduce manufacturing cost.
Detailed description of the invention:
Below in conjunction with specific embodiment, the invention will be further described.
Embodiment one: the manufacture method of a kind of hydraulic jack cold drawing welded tube of the present invention comprises the steps:
(1), slitting: be that the wide coil of strip of 27SiMn carries out slitting, according to the width of coil of strip after the diameter determination slitting of welded tube on slitter by material; The welded tube diameter such as needed is 100mm, due in roll-forming process, the width of coil of strip has certain elongation, the developed width of coil of strip is calculated according to this percentage elongation, carry out slitting by this width again, this width should be less than 314mm, changes according to molding curve difference;
(2), roll bending formation: the coil of strip after slitting is placed on exhibition bin, by feed mechanism, the termination of coil of strip is extracted out, send in continuous pressure roller shaping mechanism and carry out roll bending formation processing, described pressure roller shaping mechanism comprises continuous print many groups pressure roller pair, often organize pressure roller to two pressure rollers comprising misfortune conjunction mutually, gap is left between described two pressure rollers, the gap of adjacent pressure roller to correspondence is out of shape gradually, make the coil of strip through respective clearance become curved surface by plane, then become conglobate body by curved surface;
(3), the coil of strip of high-frequency welding: Cheng Yuanhou adopts high-frequency welding, and the vertical masonry joint docked its side carries out induction welding, forms welded tube;
(4), weld seam process: when welded tube not yet cools, adopt the weld seam of burring knife milling downhand welding pipe, described burring knife comprises and is arranged on removing outer deburring cutter and being arranged on outside welded tube and removes internal hair bayonet inside welded tube, go internal hair bayonet axially to insert in body from the opening part not yet becoming conglobate body, and reach the front of welding position;
(5), sizing: the welded tube formed after weld seam process is again through sizing mill sizing, and form steel pipe, temperature during sizing controls at 750 DEG C;
(6), online eddy current inspection: pop one's head in and to move in metal surface, when running into defect or the change such as material, size, make eddy current magnetism different to the reaction of coil, cause coil impedance to change, measure this variable quantity by eddy detecting instrument and just can differentiate that there are zero defect or other change in physical in metal surface;
(7), stress relief annealing: welded tube introduced heating in heating furnace and be incubated, come out of the stove with after stove cooling, obtain welded tube of annealing, object is the intensity guaranteeing welded tube, when annealing temperature is too high, processing strain recovers, the effect of work hardening can not be obtained, annealing temperature is 950 DEG C, the effect of work hardening can be obtained, this annealing in process is the annealing in process of entire body, ensure welding region and neighboring area consistent with all the other regions of welded tube in metallographic structure and mechanical performance, in order to remove the strength variance of welded tube, in the stove of welded tube, the retention time is 60 minutes,
(8), pre-straightening process: straightening temperature 600 DEG C, to reduce residual stress;
(9), Pipe Cutting: the welded tube feeding turned off in synchronization device through pre-straightening process cuts off, and turned off in synchronization device overall rectilinear motion of following welded tube in cutting-off process is synchronized with the movement, and when both move at the uniform velocity, is cut off by welded tube; It is long that welded tube can cut into 5 ~ 16m, and therefore, synchronized stroke is also that 5 ~ 16m is long, and the speed of following during cut-out is 8 ~ 160m/min;
(10), the process of normalizing air cooling: the Technology for Heating Processing adopting tempering again after quenching, hardening heat is 600 DEG C, and hardening media is water, and temperature, at 500 DEG C, reduces the residual stress of steel pipe;
(11), pinching: the welded tube after annealing carries out pinching process, make welded tube termination diametric shrinkage after extrusion die extruding, described extrusion die comprises the active section that two sections of diameters do not wait, seamlessly transit between two sections of active sections, welded tube termination enters from bigger diameter end and extrudes, the termination of extrusion die and welded tube is carrying out extruding front lubricant sprayer, with avoid extrude time wearing and tearing and surface tear, after the extrusion die extruding that 3 diameters reduce gradually, the external diameter of welded tube termination is punctured into 50% of original diameter;
(12), pickling processes: welded tube is carried out pickling, removes the scale on surface, concentration of hydrochloric acid: 7%, pickling time: 35 minutes, then neutralization pond rolls, rolling number of times: 2 times, neutralizer pH value: 9, then roll through clear water reserviors, rolling number of times: 2 times;
(13), phosphorating treatment: the chemistry forming trbasic zinc phosphate on the surface of welded tube generates overlay film, trbasic zinc phosphate concentration: 20%, Phosphating Solution temperature: 68 DEG C, phosphating time: 10 minutes, Phosphating Solution free acidity: 4, General Acidity in Phosphating Solution: 45;
(14), saponification process: form the lubricating film coateds such as metallic soap on overlay film, for follow-up cold-drawn is ready, drawn tube surface can be made brighter and cleaner, saponification temperature: 55 DEG C, saponification time: 8 minutes, saponification liquor pH value: 8;
(15), cold-drawn: will treat that cold drawing welded tube carries out cold-drawn processing, obtain drawn tube, cold-drawing technology, mould chock plug and bore spacing: 3mm, pull out machine draft: 300t, cold-drawn speed: 5m/min, opening speed: 10m/min, drawn tube length: maximum 20m, drawn tube external diameter: 85mm, drawn tube wall thickness: 3mm;
(16), induction furnace Quenching Treatment: induction furnace hardening heat is 500 DEG C, and hardening media is water, reduces the residual stress of steel pipe;
(17), temper in batch-type furnace: the temperature of tempering air cooling is 350 DEG C, to reduce residual stress;
(18), straightening processing: be incubated 30 minutes in low-temp temper furnace, then carry out thermal straightening process, thermal straightening temperature 400 DEG C, to reduce residual stress;
(19), finish-boring rolling: pass through roll forming, rolling surface forms one deck flow harden layer, decrease elasticity and the plastic deformation of the secondary contact surface of grinding, thus improve the wearability on polished rod surface, case hardness and intensity improve, improve the wearability of surface of the work, corrosion resistance and conformability, reach yield strength (MPa): 850, tensile strength (MPa): 870;
(20), magnetic leakage detection: under suitable lift-off gap, inspection speed and the intensity of magnetization, to steel pipe vertical, horizontal defects detection, underproof welded tube is rejected, and makes mark at rejected region;
(21), Pipe Cutting is measured: carry out fixed length cutting to steel pipe, after cutting, pipe is smooth.
After testing, institute's inspection project meets GB/T3639-2009 standard to the product that the present embodiment obtains, and product is qualified, meets the requirement of user.
The contrast in technical performance of a kind of hydraulic jack cold drawing welded tube and conventional steel pipe
Embodiment two: the manufacture method of a kind of hydraulic jack cold drawing welded tube of the present invention comprises the steps:
(1), slitting: be that the wide coil of strip of 27SiMn carries out slitting, according to the width of coil of strip after the diameter determination slitting of welded tube on slitter by material; The welded tube diameter such as needed is 200mm, due in roll-forming process, the width of coil of strip has certain elongation, the developed width of coil of strip is calculated according to this percentage elongation, carry out slitting by this width again, this width should be less than 628mm, changes according to molding curve difference;
(2), roll bending formation: the coil of strip after slitting is placed on exhibition bin, by feed mechanism, the termination of coil of strip is extracted out, send in continuous pressure roller shaping mechanism and carry out roll bending formation processing, described pressure roller shaping mechanism comprises continuous print many groups pressure roller pair, often organize pressure roller to two pressure rollers comprising misfortune conjunction mutually, gap is left between described two pressure rollers, the gap of adjacent pressure roller to correspondence is out of shape gradually, make the coil of strip through respective clearance become curved surface by plane, then become conglobate body by curved surface;
(3), the coil of strip of high-frequency welding: Cheng Yuanhou adopts high-frequency welding, and the vertical masonry joint docked its side carries out induction welding, forms welded tube;
(4), weld seam process: when welded tube not yet cools, adopt the weld seam of burring knife milling downhand welding pipe, described burring knife comprises and is arranged on removing outer deburring cutter and being arranged on outside welded tube and removes internal hair bayonet inside welded tube, go internal hair bayonet axially to insert in body from the opening part not yet becoming conglobate body, and reach the front of welding position;
(5), sizing: the welded tube formed after weld seam process is again through sizing mill sizing, and form steel pipe, temperature during sizing controls at 800 DEG C;
(6), online eddy current inspection: pop one's head in and to move in metal surface, when running into defect or the change such as material, size, make eddy current magnetism different to the reaction of coil, cause coil impedance to change, measure this variable quantity by eddy detecting instrument and just can differentiate that there are zero defect or other change in physical in metal surface;
(7), stress relief annealing: welded tube introduced heating in heating furnace and be incubated, come out of the stove with after stove cooling, obtain welded tube of annealing, object is the intensity guaranteeing welded tube, when annealing temperature is too high, processing strain recovers, the effect of work hardening can not be obtained, annealing temperature is 980 DEG C, the effect of work hardening can be obtained, this annealing in process is the annealing in process of entire body, ensure welding region and neighboring area consistent with all the other regions of welded tube in metallographic structure and mechanical performance, in order to remove the strength variance of welded tube, in the stove of welded tube, the retention time is 90 minutes,
(8), pre-straightening process: straightening temperature 450 DEG C, to reduce residual stress;
(9), Pipe Cutting: the welded tube feeding turned off in synchronization device through pre-straightening process cuts off, and turned off in synchronization device overall rectilinear motion of following welded tube in cutting-off process is synchronized with the movement, and when both move at the uniform velocity, is cut off by welded tube; It is long that welded tube can cut into 5 ~ 16m, and therefore, synchronized stroke is also that 5 ~ 16m is long, and the speed of following during cut-out is 8 ~ 160m/min;
(10), the process of normalizing air cooling: the Technology for Heating Processing adopting tempering again after quenching, hardening heat is 650 DEG C, and hardening media is water, and temperature, at 550 DEG C, reduces the residual stress of steel pipe;
(11), pinching: the welded tube after annealing carries out pinching process, make welded tube termination diametric shrinkage after extrusion die extruding, described extrusion die comprises the active section that two sections of diameters do not wait, seamlessly transit between two sections of active sections, welded tube termination enters from bigger diameter end and extrudes, the termination of extrusion die and welded tube is carrying out extruding front lubricant sprayer, with avoid extrude time wearing and tearing and surface tear, after the extrusion die extruding that 1 diameter reduces gradually, the external diameter of welded tube termination is punctured into 75% of original diameter;
(12), pickling processes: welded tube is carried out pickling, removes the scale on surface, concentration of hydrochloric acid: 19%, pickling time: 60 minutes, then neutralization pond rolls, rolling number of times: 3 times, neutralizer pH value: 10, then roll through clear water reserviors, rolling number of times: 3 times;
(13), phosphorating treatment: the chemistry forming trbasic zinc phosphate on the surface of welded tube generates overlay film, trbasic zinc phosphate concentration: 30%, Phosphating Solution temperature: 75 DEG C, phosphating time: 20 minutes, Phosphating Solution free acidity: 7, General Acidity in Phosphating Solution: 75;
(14), saponification process: form the lubricating film coateds such as metallic soap on overlay film, for follow-up cold-drawn is ready, drawn tube surface can be made brighter and cleaner, saponification temperature: 75 DEG C, saponification time: 15 minutes, saponification liquor pH value: 9;
(15), cold-drawn: will treat that cold drawing welded tube carries out cold-drawn processing, obtain drawn tube, cold-drawing technology, mould chock plug and bore spacing: 5mm, pull out machine draft: 400t, cold-drawn speed: 30m/min, opening speed: 50m/min, drawn tube length: maximum 20m, drawn tube external diameter: 250mm, drawn tube wall thickness: 20mm;
(16), induction furnace Quenching Treatment: induction furnace hardening heat is 550 DEG C, and hardening media is water, reduces the residual stress of steel pipe;
(17), temper in batch-type furnace: the temperature of tempering air cooling is 380 DEG C, to reduce residual stress;
(18), straightening processing: be incubated 45 minutes in low-temp temper furnace, then carry out thermal straightening process, thermal straightening temperature 500 DEG C, to reduce residual stress;
(19), finish-boring rolling: pass through roll forming, rolling surface forms one deck flow harden layer, decrease elasticity and the plastic deformation of the secondary contact surface of grinding, thus improve the wearability on polished rod surface, case hardness and intensity improve, and improve the wearability of surface of the work, corrosion resistance and conformability;
(20), magnetic leakage detection: under suitable lift-off gap, inspection speed and the intensity of magnetization, to steel pipe vertical, horizontal defects detection, underproof welded tube is rejected, and makes mark at rejected region;
(21), Pipe Cutting is measured: carry out fixed length cutting to steel pipe, after cutting, pipe is smooth.
Embodiment three: the manufacture method of a kind of hydraulic jack cold drawing welded tube of the present invention comprises the steps:
(1), slitting: be that the wide coil of strip of 27SiMn carries out slitting, according to the width of coil of strip after the diameter determination slitting of welded tube on slitter by material; The welded tube diameter such as needed is 150mm, due in roll-forming process, the width of coil of strip has certain elongation, the developed width of coil of strip is calculated according to this percentage elongation, carry out slitting by this width again, this width should be less than 471mm, changes according to molding curve difference;
(2), roll bending formation: the coil of strip after slitting is placed on exhibition bin, by feed mechanism, the termination of coil of strip is extracted out, send in continuous pressure roller shaping mechanism and carry out roll bending formation processing, described pressure roller shaping mechanism comprises continuous print many groups pressure roller pair, often organize pressure roller to two pressure rollers comprising misfortune conjunction mutually, gap is left between described two pressure rollers, the gap of adjacent pressure roller to correspondence is out of shape gradually, make the coil of strip through respective clearance become curved surface by plane, then become conglobate body by curved surface;
(3), the coil of strip of high-frequency welding: Cheng Yuanhou adopts high-frequency welding, and the vertical masonry joint docked its side carries out induction welding, forms welded tube;
(4), weld seam process: when welded tube not yet cools, adopt the weld seam of burring knife milling downhand welding pipe, described burring knife comprises and is arranged on removing outer deburring cutter and being arranged on outside welded tube and removes internal hair bayonet inside welded tube, go internal hair bayonet axially to insert in body from the opening part not yet becoming conglobate body, and reach the front of welding position;
(5), sizing: the welded tube formed after weld seam process is again through sizing mill sizing, and form steel pipe, temperature during sizing controls at 780 DEG C;
(6), online eddy current inspection: pop one's head in and to move in metal surface, when running into defect or the change such as material, size, make eddy current magnetism different to the reaction of coil, cause coil impedance to change, measure this variable quantity by eddy detecting instrument and just can differentiate that there are zero defect or other change in physical in metal surface;
(7), stress relief annealing: welded tube introduced heating in heating furnace and be incubated, come out of the stove with after stove cooling, obtain welded tube of annealing, object is the intensity guaranteeing welded tube, when annealing temperature is too high, processing strain recovers, the effect of work hardening can not be obtained, annealing temperature is 960 DEG C, the effect of work hardening can be obtained, this annealing in process is the annealing in process of entire body, ensure welding region and neighboring area consistent with all the other regions of welded tube in metallographic structure and mechanical performance, in order to remove the strength variance of welded tube, in the stove of welded tube, the retention time is 80 minutes,
(8), pre-straightening process: straightening temperature 620 DEG C, to reduce residual stress;
(9), Pipe Cutting: the welded tube feeding turned off in synchronization device through pre-straightening process cuts off, and turned off in synchronization device overall rectilinear motion of following welded tube in cutting-off process is synchronized with the movement, and when both move at the uniform velocity, is cut off by welded tube; It is long that welded tube can cut into 5 ~ 16m, and therefore, synchronized stroke is also that 5 ~ 16m is long, and the speed of following during cut-out is 8 ~ 160m/min;
(10), the process of normalizing air cooling: the Technology for Heating Processing adopting tempering again after quenching, hardening heat is 620 DEG C, and hardening media is water, and temperature, at 520 DEG C, reduces the residual stress of steel pipe;
(11), pinching: the welded tube after annealing carries out pinching process, make welded tube termination diametric shrinkage after extrusion die extruding, described extrusion die comprises the active section that two sections of diameters do not wait, seamlessly transit between two sections of active sections, welded tube termination enters from bigger diameter end and extrudes, the termination of extrusion die and welded tube is carrying out extruding front lubricant sprayer, with avoid extrude time wearing and tearing and surface tear, after the extrusion die extruding that 2 diameters reduce gradually, the external diameter of welded tube termination is punctured into 63% of original diameter;
(12), pickling processes: welded tube is carried out pickling, removes the scale on surface, concentration of hydrochloric acid: 10%, pickling time: 45 minutes, then neutralization pond rolling, rolling number of times: 2.5 times, neutralizer pH value: 9.5, then through clear water reserviors rolling, rolling number of times: 2.5 times;
(13), phosphorating treatment: the chemistry forming trbasic zinc phosphate on the surface of welded tube generates overlay film, trbasic zinc phosphate concentration: 25%, Phosphating Solution temperature: 70 DEG C, phosphating time: 15 minutes, Phosphating Solution free acidity: 6, General Acidity in Phosphating Solution: 60;
(14), saponification process: form the lubricating film coateds such as metallic soap on overlay film, for follow-up cold-drawn is ready, drawn tube surface can be made brighter and cleaner, saponification temperature: 60 DEG C, saponification time: 10 minutes, saponification liquor pH value: 8.5;
(15), cold-drawn: will treat that cold drawing welded tube carries out cold-drawn processing, obtain drawn tube, cold-drawing technology, mould chock plug and bore spacing: 4mm, pull out machine draft: 350t, cold-drawn speed: 20m/min, opening speed: 30m/min, drawn tube length: maximum 20m, drawn tube external diameter: 200mm, drawn tube wall thickness: 15mm;
(16), induction furnace Quenching Treatment: induction furnace hardening heat is 520 DEG C, and hardening media is water, reduces the residual stress of steel pipe;
(17), temper in batch-type furnace: the temperature of tempering air cooling is 370 DEG C, to reduce residual stress;
(18), straightening processing: be incubated 40 minutes in low-temp temper furnace, then carry out thermal straightening process, thermal straightening temperature 450 DEG C, to reduce residual stress;
(19), finish-boring rolling: pass through roll forming, rolling surface forms one deck flow harden layer, decrease elasticity and the plastic deformation of the secondary contact surface of grinding, thus improve the wearability on polished rod surface, case hardness and intensity improve, and improve the wearability of surface of the work, corrosion resistance and conformability;
(20), magnetic leakage detection: under suitable lift-off gap, inspection speed and the intensity of magnetization, to steel pipe vertical, horizontal defects detection, underproof welded tube is rejected, and makes mark at rejected region;
(21), Pipe Cutting is measured: carry out fixed length cutting to steel pipe, after cutting, pipe is smooth.

Claims (1)

1. the manufacture method of a hydraulic jack cold drawing welded tube comprises the steps:
(1), slitting: be that the wide coil of strip of 27SiMn carries out slitting, according to the width of coil of strip after the diameter determination slitting of welded tube on slitter by material;
(2), roll bending formation: the coil of strip after slitting is placed on exhibition bin, by feed mechanism, the termination of coil of strip is extracted out, send in continuous pressure roller shaping mechanism and carry out roll bending formation processing, described pressure roller shaping mechanism comprises continuous print many groups pressure roller pair, often organize pressure roller to two pressure rollers comprising misfortune conjunction mutually, gap is left between described two pressure rollers, the gap of adjacent pressure roller to correspondence is out of shape gradually, make the coil of strip through respective clearance become curved surface by plane, then become conglobate body by curved surface;
(3), the coil of strip of high-frequency welding: Cheng Yuanhou adopts high-frequency welding, and the vertical masonry joint docked its side carries out induction welding, forms welded tube;
(4), weld seam process: when welded tube not yet cools, adopt the weld seam of burring knife milling downhand welding pipe, described burring knife comprises and is arranged on removing outer deburring cutter and being arranged on outside welded tube and removes internal hair bayonet inside welded tube, go internal hair bayonet axially to insert in body from the opening part not yet becoming conglobate body, and reach the front of welding position; Because roll bending formation and welding are carried out continuously, the weld seam of inner wall of welded pipe is made to be treated as a difficult problem, welded tube before cutting, its length can continue tens meters on a production line, after welding fabrication, conventional means is utilized to be to cut the weld seam of inwall or to polish process, the present invention adopts and is axially inserted in body by the body open going internal hair bayonet from Cheng Yuanqian, cross high-frequency welding position, again deburring is carried out to the weld seam in pipe, make inner wall of welded pipe smooth, for follow-up cold-drawn provides guarantee; In addition, deburring carries out in time after tube-welding, and now welded tube not yet cools, and can reduce difficulty of processing, improves deburring speed;
(5), sizing: the welded tube formed after weld seam process is again through sizing mill sizing, and form steel pipe, temperature during sizing controls at 750 ~ 800 DEG C;
(6), online eddy current inspection: pop one's head in and to move in metal surface, when running into defect or the change such as material, size, make eddy current magnetism different to the reaction of coil, cause coil impedance to change, measure this variable quantity by eddy detecting instrument and just can differentiate that there are zero defect or other change in physical in metal surface;
(7), stress relief annealing: welded tube introduced heating in heating furnace and be incubated, come out of the stove with after stove cooling, obtain welded tube of annealing, object is the intensity guaranteeing welded tube, when annealing temperature is too high, processing strain recovers, the effect of work hardening can not be obtained, annealing temperature is 950 ~ 980 DEG C, the effect of work hardening can be obtained, this annealing in process is the annealing in process of entire body, ensure welding region and neighboring area consistent with all the other regions of welded tube in metallographic structure and mechanical performance, in order to remove the strength variance of welded tube, in the stove of welded tube, the retention time is 60 ~ 90 minutes,
(8), pre-straightening process: straightening temperature 600 ~ 650 DEG C, to reduce residual stress;
(9), Pipe Cutting: the welded tube feeding turned off in synchronization device through pre-straightening process cuts off, and turned off in synchronization device overall rectilinear motion of following welded tube in cutting-off process is synchronized with the movement, and when both move at the uniform velocity, is cut off by welded tube; The program adopts the method for synchronization to be cut off by welding pipe fixed length, ensure that welding, roll bending formation, weld seam process are carried out continuously in non-stop-machine situation, can improve speed of production;
(10), the process of normalizing air cooling: the Technology for Heating Processing adopting tempering again after quenching, hardening heat is 600 ~ 650 DEG C, and hardening media is water, and temperature, at 500 ~ 550 DEG C, reduces the residual stress of steel pipe;
(11), pinching: the welded tube after annealing carries out pinching process, make welded tube termination diametric shrinkage after extrusion die extruding, described extrusion die comprises the active section that two sections of diameters do not wait, seamlessly transit between two sections of active sections, welded tube termination enters from bigger diameter end and extrudes, the termination of extrusion die and welded tube is carrying out extruding front lubricant sprayer, with avoid extrude time wearing and tearing and surface tear, after the extrusion die extruding that 1 ~ 3 diameter reduces gradually, the external diameter of welded tube termination is punctured into 50 ~ 75% of original diameter;
(12), pickling processes: welded tube is carried out pickling, removes the scale on surface, concentration of hydrochloric acid: 7 ~ 19%, pickling time: 35 ~ 60 minutes, then neutralization pond rolling, rolling number of times: 2 ~ 3 times, neutralizer pH value: 9 ~ 10, then through clear water reserviors rolling, rolling number of times: 2 ~ 3 times;
(13), phosphorating treatment: the chemistry forming trbasic zinc phosphate on the surface of welded tube generates overlay film, trbasic zinc phosphate concentration: 20 ~ 30%, Phosphating Solution temperature: 68 ~ 75 DEG C, phosphating time: 10 ~ 20 minutes, Phosphating Solution free acidity: 4 ~ 7, General Acidity in Phosphating Solution: 45 ~ 75;
(14), saponification process: form the lubricating film coateds such as metallic soap on overlay film, for follow-up cold-drawn is ready, drawn tube surface can be made brighter and cleaner, saponification temperature: 55 ~ 75 DEG C, saponification time: 8 ~ 15 minutes, saponification liquor pH value: 8 ~ 9;
(15), cold-drawn: will treat that cold drawing welded tube carries out cold-drawn processing, obtain drawn tube, cold-drawing technology, mould chock plug and bore spacing: 3 ~ 5mm, pull out machine draft: 300 ~ 400t, cold-drawn speed: 5 ~ 30m/min, opening speed: 10 ~ 50m/min, drawn tube length: maximum 20m, drawn tube external diameter: 85 ~ 250mm, drawn tube wall thickness: 3 ~ 20mm;
(16), induction furnace Quenching Treatment: induction furnace hardening heat is 500 ~ 550 DEG C, and hardening media is water, reduces the residual stress of steel pipe;
(17), temper in batch-type furnace: the temperature of tempering air cooling is 350 ~ 380 DEG C, to reduce residual stress;
(18), straightening processing: be incubated 30 ~ 45 minutes in low-temp temper furnace, then carry out thermal straightening process, thermal straightening temperature 400 ~ 500 DEG C, to reduce residual stress;
(19), finish-boring rolling: pass through roll forming, rolling surface forms one deck flow harden layer, decrease elasticity and the plastic deformation of the secondary contact surface of grinding, thus improve the wearability on polished rod surface, case hardness and intensity improve, and improve the wearability of surface of the work, corrosion resistance and conformability;
(20), magnetic leakage detection: under suitable lift-off gap, inspection speed and the intensity of magnetization, to steel pipe vertical, horizontal defects detection;
(21), Pipe Cutting is measured: carry out fixed length cutting to steel pipe, after cutting, pipe is smooth.
CN201310596957.2A 2013-11-16 2013-11-16 Manufacturing method for cold drawn welded pipe used for hydraulic oil cylinders Pending CN104646449A (en)

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CN108380692A (en) * 2018-02-12 2018-08-10 湘潭市智全机械有限公司 A kind of heavy wall stainless steel minor diameter rotary drum forming method
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CN112059540A (en) * 2020-08-11 2020-12-11 浙江晶日科技股份有限公司 Cold-drawn lamp pole and manufacturing process thereof

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