CN106238500B - A kind of production technology of rolling monolithic finned tube seamless steel pipe - Google Patents
A kind of production technology of rolling monolithic finned tube seamless steel pipe Download PDFInfo
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- CN106238500B CN106238500B CN201610695609.4A CN201610695609A CN106238500B CN 106238500 B CN106238500 B CN 106238500B CN 201610695609 A CN201610695609 A CN 201610695609A CN 106238500 B CN106238500 B CN 106238500B
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- 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
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Abstract
The invention discloses a kind of production technology of rolling monolithic finned tube seamless steel pipe, which includes the following steps：Raw material pipe is sawed-off using sawing machine, then cold centering processing is carried out to pipe by self-centering machine, pipe heats in continuous-type furnace, heating temperature is set by heating cycle requirement, by detecting heating temperature, closed-loop automatic control furnace temperature so that blank temperature is uniform in real time；Drilling/rolling technique is by pass schedule selection tool and mould and adjustment；By technological requirement, reasonable arrangement cold-drawn road number, it is lining core draw that annealing operation, final pass are arranged between passage；After draw to the steel pipe of finished size, stress relief annealing is carried out in the stove of Continuous Roller bottom；After above-mentioned technique, the monolithic finned tube quality, the precision that roll out improve, and structure property is stablized, and the security performance of the heat exchanger of making is further improved, and eliminate the potential hidden danger leaked with explosion, extend the service life period of heat exchanger.
Description
Technical field
The present invention relates to a kind of finned tube raw materials（Base）The production technology of pipe more particularly to a kind of rolling monolithic devices fin
The production technology of effective seamless steel pipe.
Background technology
Monolithic finned tube is relative to more advanced at present and use most heat exchange tube elements --- sheet string type, wound form
With the various finned tubes of winding welded type etc., in antiseptic property（Anti-corrosion）, wear-resisting property（Anti-wear） 、
Low thermal contact resistance (lower contact resistance), high stability（Higher Stability）With anti-product
Grey ability etc. has significant superiority.
In the rolling line of existing monolithic finned tube, common cold-drawn thick-walled seamless steel pipes are used.It is several to leave face
Problem：1. dimensional tolerance
Meet the common cold-drawn thick-walled seamless steel pipes of existing national standards, since dimensional tolerance is big, especially " bias " refers to
It is big to mark deviation, be easy to cause the finned tube base tube wall thickness shut out（S）Size circumferential direction deviation is big, finned tube fin height（H）Circumferential,
The defects of axial inconsistent.So as to cause：
1）Finned tube straightness after rolling（At present without national standard）Difference, and be irreversible, it influences installation, make heat exchanger
Precision；
2）It increases that finned tube heat exchange property is circumferentially poor, influences the consistency of heat exchanger efficiency；
3）The bearing capacity of finned tube is by minimum basis thickness of pipe wall（S）It determines, dimensional discrepancy senior general reduces its pressure-bearing energy
Power, safety coefficient reduce, and easily occur equipment, the safety accident such as leaking, explode at minimum wall thickness (MINI W.) when serious, cause huge damage
It loses.
2. defective workmanship and structure property
Since finned tube is by rolling extrusion forming, the H/b ratios of fin are big, and there is violent deformations, cause
The tissue deterioration trend of fin is big, easily forms non-equilibrium microstructure, when being produced especially with materials such as middle and high carbon, steel alloys, group
It is more serious to knit deterioration, the quality in kind of finished product finned tube can be influenced.This requires the groups that raw material seamless steel pipe itself will have
Knit basis and quality in kind.
1）In existing cold-drawn production seamless steel pipe mode, in order to reduce cost, " empty sinking " technique is used too much, easily
" crackle " defect for thick-walled seamless steel pipes inner wall occur, even if this defect can not be examined using methods of detection such as vortex, ultrasounds
Go out.
This defect further expands during rolled finned tube, when finished product finned tube pressure testing cannot detect,
Causing the heat exchanger that is made of this finned tube, there is the potential risks leaked with explosion；
2）Existing raw material seamless steel pipe delivery is full annealing（≧900℃）State, before rolled finned tube again
By being heated to 1200 DEG C or so, easily there is coarse grains, tissue looseness, skin decarburization of material etc. and lacks in repetition high-temperature heating
It falls into, forms fin surface " crackle " defect in violent crimp, and cause waste product；When this " crackle " defect is present in
When inner surface, there is the potential risks leaked with explosion for the heat exchanger made of this finned tube.
Invention content
The technical problem to be solved in the present invention is to provide it is a kind of eliminate " crackle " of thick-walled pipe, monolithic finned tube quality,
Precision improves, and structure property is stablized, and the security performance of the heat exchanger of making is further improved, eliminate potential leakage with
The hidden danger of explosion extends the production technology of the service life pepriodic rolling monolithic finned tube seamless steel pipe of heat exchanger.
In order to solve the above technical problem, the present invention provides a kind of productions of rolling monolithic finned tube seamless steel pipe
Technique, it is characterised in that：The production technology includes the following steps：
Step 1：Raw material pipe based process；
Raw material pipe is sawed-off using sawing machine, and pipe length is determined according to production tube setting length, then passes through self-centering
Machine carries out cold centering processing to pipe, gets internal point on pipe, a diameter of 1/3 pipe diameter of internal point, and internal point is long
Degree is 10-15 mm；
Step 2：Heat treatment；
Pipe is sent into continuous-type furnace after centering is handled and is heated, temperature is heated according to pipe specification different set
Degree is different, if 10 steel or/and 20 steel, heating temperature are set as 1220 ± 15 DEG C, if 35 steel or/and 45 steel or/and steel alloy, add
Hot temperature is set as 1200 ± 15 DEG C, is measured in real time to heating temperature by real-time detection apparatus, is set automatically using closed loop
It is standby to automatically control in-furnace temperature, keep its blank temperature uniform, the closed loop automatic equipment control accuracy is ± 15 DEG C；
Step 3：Drilling/rolling is processed；
Pipe after heating is processed into eleven punch 11 using punch, piercer roll rotates in the same direction, and circular pipe blank enters
It after roll, is on the one hand driven by the frictional force between metal and roll, makees the rotation in anti-roller rotational direction, pipe is again in an axial direction
Mobile, helically motion state makes hollow billet after perforation, and hair thickness of pipe wall is partially poor≤0.3 mm；
Step 4：Draw processing；
Different according to steel pipe specification, Tube Drawing road number is different, by drawbench by steel pipe in the way of strong pull
The cold drawing steel tube smaller than raw steel pipe diameter is pulled into, steel pipe carries out multiple cold-drawn, to eliminate draw stress, is set between cold-drawn passage
Determine annealing operation, after annealing, steel pipe forms final pass, the steel pipe finished product wall thickness reducing amount in lining core draw by lining core draw
≤ 0.3mm, steel pipe finished diameter Gong Cha≤± 0.1mm, Bi thickness Gong Cha≤± 0.2mm, wall thickness circumferential direction Pian Cha≤0.2mm；
Step 5：Production tube stress relief annealing；
After draw to the steel pipe of finished size, stress relief annealing is carried out in the stove of Continuous Roller bottom, moves back fiery Wen Du≤700
DEG C, time inside furnace is 20-25 min；
Step 6：Finishing；
Production tube after stress relief annealing is sent into Runout area, aligned, sawing end to end and product inspection, examine steel
Pipe size specification, inside and outside surface quality and eddy current inspection, certified products storage packaging.
Preferably, the raw material pipe steel substrate material is carbon steel, steel alloy, stainless steel, nonferrous materials.
Preferably, in step 4, lining core road number≤2, empty sinking road number≤1.
Compared with prior art, the present invention has following advantages：
Pipe is sent into continuous-type furnace after centering is handled and is heated, temperature is heated according to pipe specification different set
Degree is different, if 10 or/and 20 steel, heating temperature are set as 1220 ± 15 DEG C, if 35 or/and 45 or/and steel alloy, heating temperature
It is set as 1200 ± 15 DEG C, heating temperature is measured in real time by real-time detection apparatus, it is automatic using closed loop automatic equipment
In-furnace temperature is controlled, keeps its blank temperature uniform, the closed loop automatic equipment control accuracy is ± 15 DEG C, which can
It, can be to reach≤0.3mm to ensure that the hollow billet that pipe is pierced by has extraordinary wall thickness circumferential direction deviation precision；
Steel pipe is pulled into the cold drawing steel tube smaller than raw steel pipe diameter in the way of strong pull by drawbench, steel pipe carries out
Multiple cold-drawn sets annealing operation to eliminate draw stress between cold-drawn passage, and after annealing, steel pipe is pulled out by lining core
System forms final pass, steel pipe finished product Jian Bi Liang≤0.3mm in lining core draw, steel pipe finished diameter Gong Cha≤± 0.1mm, wall
Thick Gong Cha≤± 0.2mm, wall thickness circumferential direction Pian Cha≤0.2mm, the cold-drawing technology can eliminate " crackle " defect of thick-walled pipe；
Final pass uses the stress relief annealing of low temperature, can repeatedly be heated at high temperature the metallographic structure easily occurred to avoid steel pipe
The defects of coarse grains, skin decarburization；
It can provide high-precision rolled fin effective raw material seamless steel pipe using the technique, wall thickness is partially poor≤and 0.2
mm ；Monolithic finned tube quality that the roll seamless steel tube of process technology scheme production goes out, precision improve, and structure property is steady
Fixed, the security performance of the heat exchanger of making is further improved, and is eliminated the potential hidden danger leaked with explosion, is extended and change
The service life period of hot device.
Description of the drawings
Fig. 1 is the flow chart of the production technology of present invention rolling monolithic finned tube seamless steel pipe.
Specific implementation mode
As shown in Figure 1, the production technology of rolling monolithic finned tube seamless steel pipe, which includes following step
Suddenly：
Pipe must use sawing machine sawed-off before mother tube prepares perforation, and sawed-off length is determined according to production tube process length；
Pipe after sawed-off, must be in self-centering machine（Drilling machine）It is upper to carry out cold centering, get internal point, the internal point a diameter of 1/3
Pipe diameter, centering hole length are 10-15 mm；
Pipe is sent into continuous-type furnace after centering is handled and is heated, temperature is heated according to pipe specification different set
Degree is not
Together, if 10 or/and 20 steel, heating temperature are set as 1220 ± 15 DEG C, if 35 or/and 45 low-alloy steel, heating temperature
Degree is set as 1200 ± 15 DEG C, is measured in real time to heating temperature by real-time detection apparatus, certainly using closed loop automatic equipment
Dynamic control in-furnace temperature so that blank temperature is uniform, and the closed loop automatic equipment control accuracy is ± 15 DEG C；
Pipe after heating is processed into eleven punch 11 using punch, piercer roll rotates in the same direction, and circular pipe blank enters
It after roll, is on the one hand driven by the frictional force between metal and roll, makees the rotation in anti-roller rotational direction, pipe is again in an axial direction
Mobile, helically motion state makes hollow billet after perforation, and hair thickness of pipe wall is partially poor≤0.3 mm, and drilling/rolling technique presses pass schedule
Tool and mould and adjustment are selected, the high quality hollow billet of Bi thickness Pian Cha≤0.3 mm can be obtained.
Different according to pipe specification, Tube Drawing road number is different, is pulled out in the way of strong pull steel pipe by drawbench
At the cold drawing steel tube smaller than former bar diameter, steel pipe carries out multiple cold-drawn, for improving steel strength；It is set between cold-drawn passage
Determine annealing operation, after annealing, steel pipe forms final pass, the steel pipe finished product wall thickness reducing amount in lining core draw by lining core draw
≤ 0.3mm, steel pipe finished product produce available accuracy in batches：Steel pipe finished diameter Gong Cha≤± 0.1mm, Bi thickness Gong Cha≤± 0.2mm
, wall thickness circumferential direction deviation（S1-S2）≤ 0.2mm, by technological requirement, reasonable arrangement cold-drawn road number arranges lehr attendant between passage
Sequence.
Stress relief annealing：After draw to the steel pipe of finished size, stress relief annealing is carried out in the stove of Continuous Roller bottom, is annealed
Wen Du≤700 DEG C, time inside furnace are 20-25 min；
Finishing：Production tube after stress relief annealing is sent into Runout area, aligned, sawing end to end and product inspection, inspection
Test steel pipe sizes specification, inside and outside surface quality and eddy current inspection, certified products storage packaging.
Above-mentioned technique can provide high-precision rolled fin effective raw material seamless steel pipe, and wall thickness is partially poor≤0.2 mm；It can
To eliminate " crackle " defect of thick-walled pipe；The metallographic structure coarse grains for repeating to be heated at high temperature tubing, skin decarburization etc. is solved to lack
It falls into；Monolithic finned tube quality that the roll seamless steel tube of process technology scheme production goes out, precision improve, and structure property is steady
Fixed, the security performance of the heat exchanger of making is further improved, and is eliminated the potential hidden danger leaked with explosion, is extended and change
The service life period of hot device.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
All any modification, equivalent and improvement etc., should all be included in the protection scope of the present invention made by within refreshing and principle.
Claims (4)
1. a kind of production technology of rolling monolithic finned tube seamless steel pipe, it is characterised in that：The production technology includes as follows
Step：
Step 1：Raw material pipe based process；
Raw material pipe is sawed-off using sawing machine, and pipe length is determined according to production tube setting length, then passes through self-centering machine pair
Pipe carries out cold centering processing, and internal point, a diameter of 1/3 pipe diameter of internal point are got on pipe, and centering hole length is
10-15 mm；
Step 2：Heat treatment；
Pipe is sent into continuous-type furnace after centering is handled and is heated, not according to pipe material different set heating temperature
Together, if 10 steel or 20 steel, heating temperature are set as 1220 ± 15 DEG C, if 35 steel or 45 steel or steel alloy, heating temperature are set as
1200 ± 15 DEG C, heating temperature is measured in real time by real-time detection apparatus, stove is automatically controlled using closed loop automatic equipment
Interior temperature keeps its blank temperature uniform, and the closed loop automatic equipment control accuracy is ± 15 DEG C；
Step 3：Drilling/rolling is processed；
Pipe after heating is processed into eleven punch 11 using punch, piercer roll rotates in the same direction, and circular pipe blank enters roll
Afterwards, it is on the one hand driven by the frictional force between metal and roll, makees the rotation in anti-roller rotational direction, while pipe is again in an axial direction
Mobile, helically motion state makes hollow billet after perforation, and hair thickness of pipe wall is partially poor≤0.3 mm；
Step 4：Draw processing；
Different according to steel pipe specification, cold-drawn road number is different, is pulled into steel pipe than original in the way of strong pull by drawbench
The small cold drawing steel tube of diameter of steel tube, steel pipe carry out multiple cold-drawn, and to eliminate draw stress, lehr attendant is set between cold-drawn passage
Sequence, after annealing, steel pipe forms final pass by lining core draw, steel pipe finished product Jian Bi Liang≤0.3mm in lining core draw,
Steel pipe finished diameter Gong Cha≤± 0.1mm, Bi thickness Gong Cha≤± 0.2mm, wall thickness circumferential direction Pian Cha≤0.2mm；
Step 5：Production tube stress relief annealing；
After draw to the steel pipe of finished size, stress relief annealing is carried out in the stove of Continuous Roller bottom, moves back fiery Wen Du≤700 DEG C,
The stove time is 20-25 min；
Step 6：Finishing；
Production tube after stress relief annealing is sent into Runout area, aligned, sawing end to end and product inspection, examine steel pipe ruler
Very little specification, inside and outside surface quality and eddy current inspection, certified products storage packaging.
2. the production technology of rolling monolithic finned tube seamless steel pipe according to claim 1, it is characterised in that：It is described
Raw material pipe steel substrate material is carbon steel, steel alloy.
3. the production technology of rolling monolithic finned tube seamless steel pipe according to claim 1, it is characterised in that：Step
In 1, cold centering processing is carried out to pipe, internal point, a diameter of 1/3 pipe diameter of internal point, internal point are got on pipe
Length is 10-15 mm.
4. the production technology of rolling monolithic finned tube seamless steel pipe according to claim 1, it is characterised in that：Step
In 4, lining core road number≤2, empty sinking road number≤1.
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| CN201610695609.4A CN106238500B (en) | 2016-08-22 | 2016-08-22 | A kind of production technology of rolling monolithic finned tube seamless steel pipe |
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| CN201610695609.4A CN106238500B (en) | 2016-08-22 | 2016-08-22 | A kind of production technology of rolling monolithic finned tube seamless steel pipe |
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| CN106238500B true CN106238500B (en) | 2018-09-07 |
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| CN106767096B (en) * | 2016-12-29 | 2019-06-28 | 浙江久立特材科技股份有限公司 | A kind of corrosion resistant alloy finned tube and manufacturing method |
| CN111214749B (en) * | 2019-12-18 | 2024-04-23 | 四川扬子江医疗器械有限公司 | High-pressure balloon catheter and manufacturing method thereof |
| 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 |
| CN112719801A (en) * | 2020-12-21 | 2021-04-30 | 常熟市无缝钢管有限公司 | Three-way composite special-shaped steel pipe and machining method thereof |
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| CN101130197A (en) * | 2006-09-26 | 2008-02-27 | 李永立 | Cold drawing, cold rolling production method for high-accuracy weldless steel tube |
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| CN103447365A (en) * | 2012-05-29 | 2013-12-18 | 候彩花 | Semi-automatic hot rolling device for integral spiral finned tubes |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN100522405C (en) * | 2004-01-16 | 2009-08-05 | 住友金属工业株式会社 | Method for producing seamless pipe |
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| 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 |
| 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 |
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Effective date of registration: 20180720 Address after: 225312 Century Avenue, Kowloon Town, Taizhou, Jiangsu Province, 69-5 Applicant after: Cang Dongsheng Address before: 225312 Jiangsu Taizhou Jiulong precision twin seamless steel tube Co., Ltd. Applicant before: Huang Weiguo |
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