CN201413066Y - Shell-and-tube helix flat tube heat exchanger - Google Patents

Shell-and-tube helix flat tube heat exchanger Download PDF

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Publication number
CN201413066Y
CN201413066Y CN2009200137013U CN200920013701U CN201413066Y CN 201413066 Y CN201413066 Y CN 201413066Y CN 2009200137013 U CN2009200137013 U CN 2009200137013U CN 200920013701 U CN200920013701 U CN 200920013701U CN 201413066 Y CN201413066 Y CN 201413066Y
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China
Prior art keywords
tube
heat exchanger
shell
barrier
spiral flat
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Expired - Lifetime
Application number
CN2009200137013U
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Chinese (zh)
Inventor
陈崇刚
李立权
张卫华
邓方义
贺玲
李和杰
王声文
徐又春
张士华
王晓溥
秦岭
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YINGKOU QINGYING PETROCHEMICAL EQUIPMENT GENERAL FACTORY
Sinopec Luoyang Guangzhou Engineering Co Ltd
Original Assignee
YINGKOU QINGYING PETROCHEMICAL EQUIPMENT GENERAL FACTORY
Sinopec Luoyang Petrochemical Engineering Corp
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Priority to CN2009200137013U priority Critical patent/CN201413066Y/en
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/10—Process efficiency

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Abstract

The utility model relates to a shell-and-tube helix flat tube heat exchanger, which fundamentally solves the problems that the traditional shell-and-tube segmental baffle heat exchanger has shell-sideflowing dead zone and large shell-side pressure decrease, and is characterized in that a heat exchanging tube in a tube bundle is of a plurality of helix flat tubes, the long axis part of two adjacent helix flat tubes can be contacted with each other to form support and blocking, the short axis part correspondently forms a gap, and finally a netted flow passage is formed in the tube bundle; the gap between circular tube parts on two ends of the heat exchanging tube is provided with a cross blocking tube bracket corresponding to a partition plate inside a corresponding tube box, a plurality ofblocking tubes which are lined up in parallel with the heat exchanging tubes are arranged between the blocking tube brackets, the long axis part of the blocking and the heat exchanging tubes is contacted with each other, the short axis part is opposite to each other, a guide tightening cylinder which is provided with a plurality of annular barrier plates is sleeved on the outer part of the heat exchanging tube, and the guide tightening cylinder is welded on a barrier tube bracket. Compared with the prior helix flat tube heat exchanger, the shell-and-tube helix flat tube heat exchanger has theadvantages that the heat exchanging efficiency can be greatly improved, thereby being widely applicable to the industries such as oil refining, petroleum chemical engineering, metallurgy, electric power and the like.

Description

Shell-and-tube heat exchanger with oblate tube
Technical field
The utility model relates to a kind of shell-and-tube heat exchanger, particularly a kind of shell-and-tube heat exchanger with oblate tube that adopts spiral flat tube as heat exchanger tube.Can be widely used in industries such as oil refining, petrochemical industry, metallurgy, electric power.
Background technology
Heat exchanger is the key equipment in the thermal procession, is widely used in fields such as the energy, power, chemical industry, metallurgy, machinery, traffic, aeronautics and space.Simultaneously, heat exchanger also is the necessaries that utilizes the energy and energy savings.The kind of heat exchanger is a lot, and shell-and-tube heat exchanger is easy to make because of having, cost is lower, cleaning is convenient, adaptability is strong, treating capacity is big, reliable operation, selection range is wide and the characteristics such as operating mode that are suitable for HTHP, uses very general in every profession and trade.Yet traditional shell-and-tube heat exchanger mostly is segmental baffle board heat exchangers, this heat exchanger is when having the shell-and-tube heat exchanger advantage, the defective of himself is also arranged, as have shell side flow dead, big, the easy fouling of shell side pressure loss and tube bank induced vibration etc. takes place easily.As when the design pipe shell formula heat exchanger, the situation that the two media flow differs greatly appears sometimes.In this case, it is inappropriate that the medium that flow is big is walked tube side, and this is because number of tube passes even number normally change number of tube passes tube side speed will be multiplied, thereby it is excessive to cause pressure to fall.Arrange the big medium of flow to walk shell side, if select the shell-and-tube segmental baffle board heat exchangers for use, shell side pressure is fallen very big, is difficult in the practical application accept.In order effectively to overcome the defective that traditional segmental baffle board heat exchangers exists, how association area personnel are to changing the flow regime of shell side, tube side fluid, improve heat-transfer effect, big quantity research has been carried out in aspects such as raising heat transfer efficiency, wherein also comprises and uses the research of spiral flat tube as heat exchanger tube.Studies show that the shell side of this heat exchanger has been cancelled additional tube bundle support thing, does not establish any supporting member, has saved material and cost.Closely contact forms spiral flow channel at heat exchanger shell pass between the spiral flat tube, also plays the effect of mutual supporting simultaneously.This structure all produces with the rotating flow tube side fluid and shell-side fluid to be the complexity of principal character to flow, and obtains stronger rotation disturbance, thereby has strengthened diabatic process significantly, and the while has also significantly reduced the shell side pressure loss.By a large amount of experimental studies, prove the ratio ho/ Δ P of heat exchanger with oblate shell side film coefficient and shell-side pressure drop, high more a lot of than segmental baffle board heat exchangers; The ratio hi/ Δ P of tube side film coefficient and tube side pressure drop, also than light pipe height, but its comprehensive benefit is apparently higher than the light pipe segmental baffle board heat exchangers.Yet the domestic now report of also not using this class heat exchanger, it mainly is its specific embodiments, all do not reach perfect condition as the caliber of the comb mode of spiral flat tube in housing, spiral flat tube, major and minor axis size etc., its tube side film heat transfer coefficient is very big, and tube side pressure drop simultaneously is also bigger; The pressure of shell side falls very little, and the shell side film heat transfer coefficient is also less.For disclosing, " the spiral flat tube oil cooler " of CN2867256Y use the technical scheme of spiral flat tube as patent announcement number as the heat exchange oil pipe, but the description to the comb mode of spiral flat tube in housing is too simple, be unfavorable for those skilled in the art's enforcement, its scope of application is relative narrower also.So the structure of existing shell-and-tube heat exchanger with oblate tube is demanded urgently optimizing.
The utility model content
The purpose of this utility model is for a kind of shell-and-tube heat exchanger with oblate tube of reasonable in design is provided, big, easy fouling and the easy problem that induced vibration takes place to restrain fall in the shell side flow dead, the shell side pressure that have fundamentally solved the existence of conventional tube shell-type segmental baffle board heat exchangers, have reduced investment cost simultaneously.Compare with existing heat exchanger with oblate, have more the advantage that significantly improves heat exchange efficiency, the scope of application is extensive.
The technical solution of the utility model is: this shell-and-tube heat exchanger with oblate tube comprises the housing that is provided with the shell side entrance and exit, be assembled in the tube bank in the housing, the bobbin carriage that is assembled in shell end is with big, little floating head, bobbin carriage is provided with the tube side entrance and exit, and its inside is provided with pass partition, it is characterized in that: heat exchanger tube is some spiral flat tubes in the described tube bank, and adjacent described spiral flat tube major axis position contacts and form to support and stop, corresponding formation gap, minor axis position, finally in described tube bank, form netted runner, it is fixing that described spiral flat tube two ends penetrate the fixed tube sheet of described tube bank and floating tubesheet and welding respectively, pass partition place in the gap of described heat exchanger tube both ends pipe part in the corresponding described bobbin carriage is provided with cross barrier tube support, the barrier tube of the some and described heat exchanger tube parallel arranged of welding between described barrier tube support, the major axis position of described barrier tube and described heat exchanger tube is in contact with one another, the minor axis position is corresponding mutually, described heat exchanger tube outer cover is equipped with water conservancy diversion and tightens up tube, described water conservancy diversion tightens up tube and is welded on the described barrier tube support, and described water conservancy diversion tightens up the outside uniform welding ring form drag baffle plate of tube, and described annular barrier plate outer is supported on the slideway that described fixed tube sheet shell side face down bonding connects.
Described spiral flat tube major axis is 30mm, and minor axis is 16.24mm, and the tube pitch of adjacent described spiral flat tube is 30mm.
Described spiral flat tube adopts special warfare to form rough outer surface in pressing process.
Advantage of the present utility model and the positive technique effect that is produced are: because the heat exchanger tube in the utility model tube bank is some spiral flat tubes, and adjacent spiral flat tube major axis position contacts and form to support and stop, corresponding formation gap, minor axis position, finally form netted runner in tube bank, the shell side medium flows in this space.The utility model has been cancelled deflection plate or rod baffle, relies on spiral flat tube to support mutually fully, has reduced investment cost.Fluid flows in the continuous screw type of tube side, and making tube side pressure fall has to a certain degree increase, makes screw type vertically in shell-side fluid and flows, and pressure falls very low, therefore is fit to very much big flow fluid and flows at shell side.Big, easy fouling and the easy problem that induced vibration takes place to restrain fall in the shell side flow dead, the shell side pressure that have fundamentally solved the existence of conventional tube shell-type segmental baffle board heat exchangers.As multi-tube pass heat exchanger, the position that the corresponding pass partition of the utility model can not be arranged the displacement heat pipe is provided with cross barrier tube support and barrier tube simultaneously, and this structure can effectively reduce short-circuit flow, has improved the heat exchange efficiency of shell side greatly.The outside suit water conservancy diversion of heat exchanger tube tightens up tube, and then whole heat exchanger tube tightens up tube with water conservancy diversion and fixes.The measures such as the annular barrier plate that welds on the tube and slideway that tighten up at water conservancy diversion have strengthened tube bank rigidity greatly, guarantee that the normal mounting of restraining uses.Fall thereby reduce tube side pressure, increase the shell side film heat transfer coefficient by major and minor axis optimized dimensions to spiral flat tube.The utility model has increased the heat transfer surface area of heat exchanger tube to the design of spiral flat tube outer surface, helps conducting heat.To sum up, the utility model is compared with existing heat exchanger with oblate, has the advantage that significantly improves heat exchange efficiency, and the scope of application is extensive.
Description of drawings
The utility model is described in further detail in conjunction with the accompanying drawings.
Fig. 1 is a kind of concrete structure schematic diagram of the present utility model;
Fig. 2 is the concrete structure schematic diagram of restraining among Fig. 1;
Fig. 3 is along the cutaway view of A-A direction among Fig. 1;
Fig. 4 is along the cutaway view of B-B direction among Fig. 1;
Fig. 5 is the structural representation of heat exchanger tube among Fig. 1.
Sequence number explanation among the figure: 1 bobbin carriage, 2 tube sides inlet, 3 fixed tube sheets, 4 barrier tube supports, 5 barrier tube, the outlet of 6 shell sides, 7 water conservancy diversion tighten up that tube, 8 annular barrier plates, 9 tube banks, 10 housings, 11 heat exchanger tubes, 12 slideways, 13 floating tubesheets, 14 little floating heads, 15 are raised the nose above water to breathe greatly, 16 shell sides enter the mouth, 17 tube sides export.
The specific embodiment
Be described in detail according to Fig. 1-5 pair the utility model.This shell-and-tube heat exchanger with oblate tube is the new type heat exchanger with self supporting structure, is to improve and optimizate to form on existing heat exchanger with oblate basis, has very important practical value.The utility model mainly partly is made up of the housing 10 that is provided with shell side inlet 16 and outlet 6, tube bank 9, the bobbin carriage 1 that is assembled in housing 10 ends and the large and small floating heads 15,14 etc. that are assembled in the housing 10.Bobbin carriage 1 is provided with tube side inlet 2 and outlet 17, and bobbin carriage 1 inside is provided with pass partition.Bobbin carriage 1, floating head can adopt Bolt Connection with connecting of housing 10.
Tube bank 9 mainly tightens up tube 7, annular barrier plate 8, slideway 12, floating tubesheet 13 etc. by fixed tube sheet 3, heat exchanger tube 11, barrier tube support 4, barrier tube 5, water conservancy diversion and forms.Wherein: heat exchanger tube is some spiral flat tubes in the tube bank, and adjacent spiral flat tube major axis position contacts and form to support and stop, corresponding formation gap, minor axis position, finally form netted runner in tube bank, the spiral flat tube two ends penetrate the fixed tube sheet of tube bank and floating tubesheet respectively and are weldingly fixed on above-mentioned two plates.Spiral flat tube is that circular light pipe is pressed into ellipse, and distortion forms then, and fluid is in the helical flow state in pipe, thereby has destroyed near the laminar boundary layer the tube wall, has improved heat transfer efficiency.The characteristics of this Pipe bundle structure are: two adjacent pipes of parallel arranged are in contact with one another at the transverse place, support mutually.In order to reach desirable heat exchange effect, the applicant finds its tube side film heat transfer coefficient α through experimental study for many years from the shell-and-tube heat exchanger with oblate tube experiment iVery big, tube side pressure drop Δ Pi is also bigger simultaneously; It is very little that Δ Po falls in the pressure of shell side, shell side film heat transfer coefficient α oAlso less.At this situation, need on structure, be improved, fall to reduce tube side pressure, increase the shell side film heat transfer coefficient, thereby make the overall performance of shell-and-tube heat exchanger with oblate tube reach optimum.
At first the caliber size of spiral flat tube is optimized.
(1) before the change: common spiral flat tube major axis a=32mm, minor axis b=12.8mm
Draw after the calculating: individual tubes tube side circulation area Si=197mm 2,
A unit shell side circulation area So=649mm 2
(2) change the back: spiral flat tube major axis a '=30mm, minor axis b '=16.24mm
Draw after the calculating: individual tubes tube side circulation area Si '=235.9mm 2,
A unit shell side circulation area So '=469.5mm 2
After promptly improving, the tube side circulation area has increased by 19.4%, and the shell side circulation area has reduced 27.6%.Theory analysis thinks that along with the increase of actual internal area, pressure falls with film heat transfer coefficient and all descends under the constant prerequisite of flow channel shape, flow; Reduce with circulation area, pressure falls with film heat transfer coefficient all to be increased.So the shell-and-tube heat exchanger with oblate tube after optimizing contrasts by experiment, the tube side pressure drop has reduced 35%, and the tube side film heat transfer coefficient reduces about 20%; Shell side pressure is fallen increases by 25% approximately, and the shell side film heat transfer coefficient has increased about 15%.By changing the shell-and-tube heat exchanger with oblate tube structure, its combination property is highly improved.In addition, after the spiral flat tube size changed, heat exchange pore centre distance was also adjusted accordingly on the corresponding tube sheet, and for the spiral flat tube of φ 25mm * 2.5mm, adjacent spiral flat tube tube pitch is reduced to 30mm by 32mm.Can arrange the heat exchanger tube more than 10% after improving on the heat exchanger of same size, promptly heat-transfer surface increases more than 10% more.Under identical operating mode, reach identical effect, heat exchanger shell footpath can dwindle, thereby has reduced investment cost.
Increase barrier tube row and be and optimize heat exchanger structure, significantly improve another big means of heat exchange efficiency.Because the particularity that shell-and-tube heat exchanger with oblate tube flows, displacement heat pipe 11 can not be afraid of in the position of pass partition in the corresponding bobbin carriage 1 on the tube sheet, and this part will produce bigger short-circuit flow, have a strong impact on shell side heat exchange effect.So the pass partition in the gaps of heat exchanger tube 11 both ends pipes part in the corresponding bobbin carriage 1 is provided with cross barrier tube support 4 respectively, and between two barrier tube supports 4 barrier tube 5 of some of welding and heat exchanger tube 11 parallel arranged, the formation barrier tube is arranged.Barrier tube 5 also adopts the spiral flat tube structure, and its major axis position is in contact with one another with the major axis position of adjacent heat exchange tubes 11, the minor axis position is corresponding mutually with the minor axis position of adjacent heat exchange tubes 11.Increase barrier tube row and can effectively reduce short-circuit flow, thereby significantly improved the heat exchange efficiency of shell side.
Heat exchanger tube 11 outer cover are equipped with water conservancy diversion and tighten up tube 7, water conservancy diversion tightens up tube 7 and is welded on the barrier tube support 4, and water conservancy diversion tightens up tube 7 outside uniform welding ring form drag baffle plates 8, and slideway 12 1 ends are fixed on fixed tube sheet 3 shell side sides, and annular barrier plate 8 fixed distance according to the rules is on slideway 12.Thereby increased tube bank rigidity, guaranteed the normal mounting use of restraining.
Annular knurl technology is all adopted on above-mentioned spiral flat tube surface, and promptly spiral flat tube adopts special warfare to form rough outer surface in pressing process, has so just increased the heat transfer surface area of heat exchanger tube, more helps conducting heat.

Claims (3)

1, a kind of shell-and-tube heat exchanger with oblate tube, comprise the housing that is provided with the shell side entrance and exit, be assembled in the tube bank in the housing, the bobbin carriage that is assembled in shell end is with big, little floating head, bobbin carriage is provided with the tube side entrance and exit, and its inside is provided with pass partition, it is characterized in that: heat exchanger tube is some spiral flat tubes in the described tube bank, and adjacent described spiral flat tube major axis position contacts and form to support and stop, corresponding formation gap, minor axis position, finally in described tube bank, form netted runner, it is fixing that described spiral flat tube two ends penetrate the fixed tube sheet of described tube bank and floating tubesheet and welding respectively, pass partition place in the gap of described heat exchanger tube both ends pipe part in the corresponding described bobbin carriage is provided with cross barrier tube support, the barrier tube of the some and described heat exchanger tube parallel arranged of welding between described barrier tube support, the major axis position of described barrier tube and described heat exchanger tube is in contact with one another, the minor axis position is corresponding mutually, described heat exchanger tube outer cover is equipped with water conservancy diversion and tightens up tube, described water conservancy diversion tightens up tube and is welded on the described barrier tube support, and described water conservancy diversion tightens up the outside uniform welding ring form drag baffle plate of tube, and described annular barrier plate outer is supported on the slideway that described fixed tube sheet shell side face down bonding connects.
2, shell-and-tube heat exchanger with oblate tube according to claim 1 is characterized in that: described spiral flat tube major axis is 30mm, and minor axis is 16.24mm, and the tube pitch of adjacent described spiral flat tube is 30mm.
3, shell-and-tube heat exchanger with oblate tube according to claim 1 and 2 is characterized in that: described spiral flat tube adopts special warfare to form rough outer surface in pressing process.
CN2009200137013U 2009-05-15 2009-05-15 Shell-and-tube helix flat tube heat exchanger Expired - Lifetime CN201413066Y (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2009200137013U CN201413066Y (en) 2009-05-15 2009-05-15 Shell-and-tube helix flat tube heat exchanger

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Application Number Priority Date Filing Date Title
CN2009200137013U CN201413066Y (en) 2009-05-15 2009-05-15 Shell-and-tube helix flat tube heat exchanger

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CN201413066Y true CN201413066Y (en) 2010-02-24

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103063056A (en) * 2012-12-28 2013-04-24 朱冬生 Pipe casing type heat exchanger
CN104713402A (en) * 2013-12-13 2015-06-17 清华大学 Sleeving method for multi-layer screw-type heat exchanging tube bundles
CN105716448A (en) * 2016-04-06 2016-06-29 太原理工大学 Shutter-shaped baffle plate fixed tube-sheet heat exchanger and machining and installing method
CN109029051A (en) * 2018-06-28 2018-12-18 浙江环宸超通量管科技有限公司 A kind of square spiral flat pipe heat exchanger and its manufacturing method

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103063056A (en) * 2012-12-28 2013-04-24 朱冬生 Pipe casing type heat exchanger
CN103063056B (en) * 2012-12-28 2015-09-09 广州以惠节能科技有限公司 A kind of shell-and-tube heat exchanger
CN104713402A (en) * 2013-12-13 2015-06-17 清华大学 Sleeving method for multi-layer screw-type heat exchanging tube bundles
CN104713402B (en) * 2013-12-13 2016-08-17 清华大学 A kind of assembling method of multi-deck screw type heat-exchanging tube bundle
CN105716448A (en) * 2016-04-06 2016-06-29 太原理工大学 Shutter-shaped baffle plate fixed tube-sheet heat exchanger and machining and installing method
CN105716448B (en) * 2016-04-06 2019-11-26 太原理工大学 A kind of blinds shape baffle plate fixed tube-sheet exchanger and processing installation method
CN109029051A (en) * 2018-06-28 2018-12-18 浙江环宸超通量管科技有限公司 A kind of square spiral flat pipe heat exchanger and its manufacturing method

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C14 Grant of patent or utility model
GR01 Patent grant
AV01 Patent right actively abandoned

Granted publication date: 20100224

Effective date of abandoning: 20090515