CN106238500A - A kind of production technology rolling monolithic finned tube seamless steel pipe - Google Patents

A kind of production technology rolling monolithic finned tube seamless steel pipe Download PDF

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Publication number
CN106238500A
CN106238500A CN201610695609.4A CN201610695609A CN106238500A CN 106238500 A CN106238500 A CN 106238500A CN 201610695609 A CN201610695609 A CN 201610695609A CN 106238500 A CN106238500 A CN 106238500A
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pipe
steel
steel pipe
temperature
cold
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CN106238500B (en
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黄卫国
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Cang Dongsheng
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黄卫国
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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

Abstract

The invention discloses a kind of production technology rolling monolithic finned tube seamless steel pipe, this technique comprises the steps: to use sawing machine sawed-off raw material pipe, by self-centering machine, pipe carried out cold centering process again, pipe heats in continuous-type furnace, heating-up temperature is set by heating cycle requirement, by detecting heating-up temperature in real time, closed-loop automatic control furnace temperature so that blank temperature is uniform;Drilling/rolling technique is pressed pass schedule and is selected tool and mould and adjustment;By technological requirement, reasonable arrangement cold-drawn road number of times, arranging annealing operation between passage, final pass is lining core draw;Draw, to after the steel pipe of finished size, carries out stress relief annealing in stove at the bottom of Continuous Roller;After using above-mentioned technique, the monolithic finned tube quality, the precision that roll out improve, and structure property is stable, and the security performance of the heat exchanger of making is further improved, and eliminate potential leakage and the hidden danger of blast, extend the cycle in service life of heat exchanger.

Description

A kind of production technology rolling monolithic finned tube seamless steel pipe
Technical field
The present invention relates to the production technology of a kind of finned tube raw material (base) pipe, refer more particularly to a kind of rolling monolithic devices fin The production technology of effective seamless steel pipe.
Background technology
Monolithic finned tube relative to the most more advanced be also to use most heat exchanger tube element sheet string type, wound form Be wound around the various finned tubes such as welding type, antiseptic property (Anti-corrosion), anti-wear performance (Anti-wear), Low thermal contact resistance (lower contact resistance), high stability (Higher Stability) and anti-long-pending The aspects such as ash ability, have significant superiority.
In the rolling line of existing monolithic finned tube, all use common cold-drawn thick-walled seamless steel pipes.Leave face several Problem: 1. dimensional tolerance
Meeting the common cold-drawn thick-walled seamless steel pipes of existing national standards, owing to dimensional tolerance is big, particularly " eccentric " index is inclined Difference is big, easily causes that finned tube base tube wall thickness (S) the size circumference deviation shut out is big, finned tube fin height (H) circumference, axially The defect such as inconsistent.Thus cause:
1) after rolling, finned tube linearity (at present without national standard) is poor, and is irreversible, and the essence of heat exchanger is installed, made in impact Degree;
2) increase finned tube heat exchange property circumference poor, affect the concordance of heat exchanger efficiency;
3) bearing capacity of finned tube is determined by minimum basis thickness of pipe wall (S), and dimensional discrepancy senior general reduces its bearing capacity, peace Overall coefficient reduces, and equipment, the security incidents such as leakage, blast easily occurs at minimum wall thickness (MINI W.), cause huge loss time serious.
2. defective workmanship and structure property
Owing to finned tube is extruded by rolling, the H/b ratio of fin is big, there is violent deformation, causes fin Tissue deterioration trend big, be easily formed non-equilibrium microstructure, when producing especially with materials such as middle and high carbon, steel alloys, tissue is disliked Change more serious, the quality in kind of finished product finned tube can be affected.This just requires the tissue base that raw material seamless steel pipe to have had itself Plinth and quality in kind.
1), during existing cold-drawn produces seamless steel pipe mode, in order to reduce cost, have employed " empty sinking " technique too much, easily " crackle " defect of thick-walled seamless steel pipes inwall occurs, even if this defect uses eddy current, the method for detection such as ultrasonic to examine Go out.
This defect expands during rolled finned tube further, when finished product finned tube pressure test can not detect, Cause the heat exchanger made of this finned tube and there is potential leakage and the risk exploded;
2) existing raw material seamless steel pipe delivery is full annealing (900 DEG C) state, passes through again before rolled finned tube
It is heated to about 1200 DEG C, repeats high-temperature heating and easily occur that the coarse grains of material, tissue looseness, skin decarburization etc. lack Fall into, violent crimp is formed fin surface " crackle " defect, and causes waste product;When this " crackle " defect is present in During inner surface, the heat exchanger made of this finned tube also exists the risk of potential leakage and blast.
Summary of the invention
The technical problem to be solved in the present invention be to provide a kind of eliminate " crackle " of thick-walled pipe, monolithic finned tube quality, Precision improve, structure property is stable, and the security performance of the heat exchanger of making is further improved, eliminate potential leakage with The hidden danger of blast, extends the production technology of pepriodic rolling in the service life monolithic finned tube seamless steel pipe of heat exchanger.
In order to solve above-mentioned technical problem, the invention provides a kind of production rolling monolithic finned tube seamless steel pipe Technique, it is characterised in that: this production technology comprises the steps:
Step 1: raw material pipe based process;
Using sawing machine sawed-off raw material pipe, pipe length determines according to production tube preseting length, then by self-centering machine pair Pipe carries out cold centering process, and pipe is got internal point, and a diameter of 1/3 pipe diameter of described internal point, internal point is a length of 10-15 mm;
Step 2: heat treated;
Pipe is sent in continuous-type furnace after centering processes and heat, according to pipe specification different set heating-up temperature not With, if 10 steel are or/and 20 steel, heating-up temperature is set as 1220 ± 15 DEG C, if 35 steel are or/and 45 steel are or/and steel alloy, heating is warm Degree is set as 1200 ± 15 DEG C, is detected heating-up temperature in real time by real-time detection apparatus, uses closed loop automatic equipment certainly Dynamic control in-furnace temperature so that it is blank temperature is uniform, and described closed loop automatic equipment control accuracy is ± 15 DEG C;
Step 3: drilling/rolling is processed;
Using perforating machine that pipe after heating is carried out perforation processing, piercer roll rotates in the same direction, and circular pipe blank enters roll After, on the one hand being driven by the frictional force between metal and roll, make the rotation in anti-roller rotational direction, pipe moves the most vertically Dynamic, helically kinestate, make hollow billet, hollow billet wall thickness deviation 0.3 mm after perforation;
Step 4: draw processes;
Different according to steel pipe specification, Tube Drawing road number of times is different, utilizes drawbench to be pulled in the way of strong pull by steel pipe The cold drawing steel tube less than former diameter of steel tube, steel pipe carries out repeatedly cold-drawn, for eliminating draw stress, sets and move back between cold-drawn passage Firer's sequence, after annealing, steel pipe forms final pass, steel pipe finished product wall thickness reducing amount in lining core draw by lining core draw 0.3mm, steel pipe finished diameter tolerance+0.1mm, wall thickness tolerance ± 0.2mm, wall thickness circumference deviation 0.2mm;
Step 5: production tube stress relief annealing;
Draw to after the steel pipe of finished size, carries out stress relief annealing in stove at the bottom of Continuous Roller, annealing temperature 700 DEG C, The stove time is 20-25 min;
Step 6: finishing;
Production tube after stress relief annealing, sends into Runout area, carry out aligning, sawing end to end and product inspection, check steel pipe chi Very little specification, surfaces externally and internally quality and eddy current inspection, certified products warehouse-in packaging.
Preferably, described raw material pipe steel substrate material is carbon steel, steel alloy, rustless steel, nonferrous materials.
Preferably, in step 4, lining core road number of times 2, empty sinking road number of times 1.
Compared with prior art, the present invention has the advantage that
Pipe is sent in continuous-type furnace after centering processes and heat, according to pipe specification different set heating-up temperature not With, if 10 or/and 20 steel, heating-up temperature is set as 1220 ± 15 DEG C, if 35 or/and 45 or/and steel alloy, heating-up temperature sets It is 1200 ± 15 DEG C, by real-time detection apparatus, heating-up temperature is detected in real time, use closed loop automatic equipment to automatically control In-furnace temperature so that it is blank temperature is uniform, and described closed loop automatic equipment control accuracy is ± 15 DEG C, and this piercing process can be protected The hollow billet that card pipe passes has extraordinary wall thickness circumference deviation precision, can reach 0.3mm;
Utilizing drawbench that steel pipe pulls in the way of strong pull the cold drawing steel tube less than former diameter of steel tube, steel pipe is carried out repeatedly Cold-drawn, for eliminating draw stress, sets annealing operation between cold-drawn passage, and after annealing, steel pipe passes through lining core draw shape Becoming final pass, steel pipe finished product wall thickness reducing amount 0.3mm in lining core draw, steel pipe finished diameter tolerance+0.1mm, wall thickness is public Difference ± 0.2mm, wall thickness circumference deviation 0.2mm, this cold-drawing technology can eliminate " crackle " defect of thick-walled pipe;
Final pass uses the stress relief annealing of low temperature, and steel pipe can be avoided to repeat the metallographic structure crystal grain that high-temperature heating easily occurs The defects such as thick, skin decarburization;
Use this technique can provide high-precision rolled fin effective raw material seamless steel pipe, wall thickness deviation 0.2 mm; Monolithic finned tube quality, precision that the roll seamless steel tube that this process technology scheme produces goes out improve, and structure property is stable, system The security performance of the heat exchanger made is further improved, and eliminates potential leakage and the hidden danger of blast, extends heat exchanger Cycle in service life.
Accompanying drawing explanation
Fig. 1 is the flow chart that the present invention rolls the production technology of monolithic finned tube seamless steel pipe.
Detailed description of the invention
As it is shown in figure 1, the production technology of rolling monolithic finned tube seamless steel pipe, this production technology includes walking as follows Rapid:
Before mother tube prepares perforation, pipe must use sawing machine sawed-off, and sawed-off length determines according to production tube process length;Sawed-off After pipe, cold centering must be carried out on self-centering machine (drilling machine), get internal point, a diameter of 1/3 pipe of described internal point Diameter, internal point a length of 10-15 mm;
Pipe is sent in continuous-type furnace after centering processes and heat, according to pipe specification different set heating-up temperature not
With, if 10 or/and 20 steel, heating-up temperature is set as 1220 ± 15 DEG C, if 35 or/and 45 low-alloy steel, heating-up temperature sets It is set to 1200 ± 15 DEG C, by real-time detection apparatus, heating-up temperature is detected in real time, use closed loop automatic equipment automatically to control In-furnace temperature processed so that blank temperature is uniform, and described closed loop automatic equipment control accuracy is ± 15 DEG C;
Using perforating machine that pipe after heating is carried out perforation processing, piercer roll rotates in the same direction, and circular pipe blank enters roll After, on the one hand being driven by the frictional force between metal and roll, make the rotation in anti-roller rotational direction, pipe moves the most vertically Dynamic, helically kinestate, make hollow billet, hollow billet wall thickness deviation 0.3 mm after perforation, drilling/rolling technique presses pass schedule choosing Select tool and mould and adjustment, the high-quality hollow billet of wall thickness deviation 0.3 mm can be obtained.
Different according to pipe specification, Tube Drawing road number of times is different, utilizes drawbench to be pulled out in the way of strong pull by steel pipe Becoming the cold drawing steel tube less than former bar diameter, steel pipe carries out repeatedly cold-drawn, is used for improving steel strength;Set between cold-drawn passage Determining annealing operation, after annealing, steel pipe forms final pass, steel pipe finished product wall thickness reducing amount in lining core draw by lining core draw 0.3mm, steel pipe finished product batch production available accuracy: steel pipe finished diameter tolerance+0.1mm, wall thickness tolerance ± 0.2mm , wall thickness circumference deviation (S1-S2) 0.2mm, by technological requirement, reasonable arrangement cold-drawn road number of times, between passage, arrange lehr attendant Sequence.
Stress relief annealing: after draw to the steel pipe of finished size, carries out stress relief annealing in stove at the bottom of Continuous Roller, annealing Temperature 700 DEG C, time inside furnace is 20-25 min;
Finishing: the production tube after stress relief annealing, sends into Runout area, carry out aligning, sawing end to end and product inspection, check steel Pipe dimensions, surfaces externally and internally quality and eddy current inspection, certified products warehouse-in packaging.
Above-mentioned technique can provide high-precision rolled fin effective raw material seamless steel pipe, wall thickness deviation 0.2 mm;Can To eliminate " crackle " defect of thick-walled pipe;Solve to repeat the metallographic structure coarse grains of high-temperature heating tubing, skin decarburization etc. to lack Fall into;Monolithic finned tube quality, precision that the roll seamless steel tube that this process technology scheme produces goes out improve, and structure property is steady Fixed, the security performance of the heat exchanger of making is further improved, and eliminates potential leakage and the hidden danger of blast, extends and change The cycle in service life of hot device.
The foregoing is only presently preferred embodiments of the present invention, not in order to limit the present invention, all spirit in the present invention and Any amendment, equivalent and the improvement etc. made within principle, should be included within the scope of the present invention.

Claims (4)

1. the production technology rolling monolithic finned tube seamless steel pipe, it is characterised in that: this production technology includes as follows Step:
Step 1: raw material pipe based process;
Using sawing machine sawed-off raw material pipe, pipe length determines according to production tube preseting length, then by self-centering machine pair Pipe carries out cold centering process, and pipe is got internal point, and a diameter of 1/3 pipe diameter of described internal point, internal point is a length of 10-15 mm;
Step 2: heat treated;
Pipe is sent in continuous-type furnace after centering processes and heat, according to pipe material different set heating-up temperature not With, if 10 steel are or/and 20 steel, heating-up temperature is set as 1220 ± 15 DEG C, if 35 steel are or/and 45 steel are or/and steel alloy, heating is warm Degree is set as 1200 ± 15 DEG C, is detected heating-up temperature in real time by real-time detection apparatus, uses closed loop automatic equipment certainly Dynamic control in-furnace temperature so that it is blank temperature is uniform, and described closed loop automatic equipment control accuracy is ± 15 DEG C;
Step 3: drilling/rolling is processed;
Using perforating machine that pipe after heating is carried out perforation processing, piercer roll rotates in the same direction, and circular pipe blank enters roll After, on the one hand driving by the frictional force between metal and roll, make the rotation in anti-roller rotational direction, pipe is the most simultaneously Mobile, helically kinestate, make hollow billet, hollow billet wall thickness deviation 0.3 mm after perforation;
Step 4: draw processes;
Different according to steel pipe specification, cold-drawn road number of times is different, utilizes drawbench that steel pipe pulls in the way of strong pull ratio former The cold drawing steel tube that diameter of steel tube is little, steel pipe carries out repeatedly cold-drawn, for eliminating draw stress, sets lehr attendant between cold-drawn passage Sequence, after annealing, steel pipe by lining core draw formed final pass, steel pipe finished product wall thickness reducing amount 0.3mm in lining core draw, Steel pipe finished diameter tolerance+0.1mm, wall thickness tolerance ± 0.2mm, wall thickness circumference deviation 0.2mm;
Step 5: production tube stress relief annealing;
Draw to after the steel pipe of finished size, carries out stress relief annealing in stove at the bottom of Continuous Roller, annealing temperature 700 DEG C, The stove time is 20-25 min;
Step 6: finishing;
Production tube after stress relief annealing, sends into Runout area, carry out aligning, sawing end to end and product inspection, check steel pipe chi Very little specification, surfaces externally and internally quality and eddy current inspection, certified products warehouse-in packaging.
The production technology of rolling monolithic finned tube seamless steel pipe the most according to claim 1, it is characterised in that: described Raw material pipe steel substrate material is carbon steel, steel alloy, rustless steel, nonferrous materials.
The production technology of rolling monolithic finned tube seamless steel pipe the most according to claim 1, it is characterised in that: step In 1, pipe is carried out cold centering process, pipe is got internal point, a diameter of 1/3 pipe diameter of described internal point, internal point A length of 10-15 mm.
The production technology of rolling monolithic finned tube seamless steel pipe the most according to claim 1, it is characterised in that: step In 4, lining core road number of times 2, empty sinking road number of times 1.
CN201610695609.4A 2016-08-22 2016-08-22 A kind of production technology of rolling monolithic finned tube seamless steel pipe Active CN106238500B (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106767096A (en) * 2016-12-29 2017-05-31 浙江久立特材科技股份有限公司 A kind of corrosion resistant alloy finned tube and manufacture method
CN111230515A (en) * 2020-02-14 2020-06-05 南京沃尔德特钢有限公司 Production method of seamless stainless steel tube for boiler heat exchanger

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2480795Y (en) * 2001-04-19 2002-03-06 丁国柱 Hot rolling formed steel base finned pipe
US20070022796A1 (en) * 2004-01-16 2007-02-01 Chihiro Hayashi Method for manufacturing seamless pipes or tubes
CN101130197A (en) * 2006-09-26 2008-02-27 李永立 Cold drawing, cold rolling production method for high-accuracy weldless steel tube
CN101650143A (en) * 2008-08-14 2010-02-17 张诗林 Finned tube and method for processing same
CN102873512A (en) * 2012-09-29 2013-01-16 攀钢集团成都钢钒有限公司 Manufacture method of large-caliber medium-and-thick-wall seamless steel tube for nuclear power plant
CN103447365A (en) * 2012-05-29 2013-12-18 候彩花 Semi-automatic hot rolling device for integral spiral finned tubes
CN104368623A (en) * 2014-11-29 2015-02-25 攀钢集团成都钢钒有限公司 Production method of large-diameter stainless steel seamless steel pipe

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2480795Y (en) * 2001-04-19 2002-03-06 丁国柱 Hot rolling formed steel base finned pipe
US20070022796A1 (en) * 2004-01-16 2007-02-01 Chihiro Hayashi Method for manufacturing seamless pipes or tubes
CN101130197A (en) * 2006-09-26 2008-02-27 李永立 Cold drawing, cold rolling production method for high-accuracy weldless steel tube
CN101650143A (en) * 2008-08-14 2010-02-17 张诗林 Finned tube and method for processing same
CN103447365A (en) * 2012-05-29 2013-12-18 候彩花 Semi-automatic hot rolling device for integral spiral finned tubes
CN102873512A (en) * 2012-09-29 2013-01-16 攀钢集团成都钢钒有限公司 Manufacture method of large-caliber medium-and-thick-wall seamless steel tube for nuclear power plant
CN104368623A (en) * 2014-11-29 2015-02-25 攀钢集团成都钢钒有限公司 Production method of large-diameter stainless steel seamless steel pipe

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106767096A (en) * 2016-12-29 2017-05-31 浙江久立特材科技股份有限公司 A kind of corrosion resistant alloy finned tube and manufacture method
CN111230515A (en) * 2020-02-14 2020-06-05 南京沃尔德特钢有限公司 Production method of seamless stainless steel tube for boiler heat exchanger

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