CN2253460Y

CN2253460Y - Needle fin tube

Info

Publication number: CN2253460Y
Application number: CN 96209163
Authority: CN
Inventors: 王励端; 高莉萍; 钱颂文; 岑汉钊; 蔡淑芬; 江楠; 马小明; 方江敏
Original assignee: South China University Of Science And Technology Development Co; BEIJING DESIGN INST CHINA PETR
Current assignee: South China University Of Science And Technology Development Co; BEIJING DESIGN INST CHINA PETR
Priority date: 1996-04-29
Filing date: 1996-04-29
Publication date: 1997-04-30
Anticipated expiration: 2006-04-29

Abstract

The utility model relates to a needle fin pipe used for consolidating heat transfer. The outside of a base pipe thereof is provided with a plurality of long and short round-rod-shaped needle fins which are arranged equidistantly, along the circumferential direction and the longitudinal direction, in the interlaced method or the sequential method, and are welded on the base pipe with a slope angle or vertically. The utility model, which can have intensive turbulent action on fluid, consolidate the heat transfer, and enlarge a secondary heat-transferring area, has high fin efficiency. When applied to high-viscosity liquid, the needle fin pipe has the functions of scaling resistance and coking resistance; when applied to high-temperature smoke gas, the needle fin pipe has the functions of dirt deposition resistance and corrosion resistance. The utility model is suitable for being used in a heat exchanger for petroleum products of the petrochemical industry and various heating furnaces or waste heat boilers of the industry.

Description

A kind of Needle fin tube

The utility model belongs to augmentation of heat transfer equipment.

Domestic heat exchange to high viscosity liquid at present because its fouling and coking are serious, is adopted light pipe mostly.In use for some time, because fouling and coking seriously make heat transfer efficiency extremely low, cause and to satisfy production requirement.For the heat exchange of oil product, adopt low fin screwed pipe though have in recent years, the expansion heat transfer area, but augmentation of heat transfer still has certain limit, serious coking is still failed to solve well, yet can not be applied in the high viscosity media such as picture residual oil, heavy oil and slurry oil, and the processing trouble.And, then mainly adopt draw ratio extremely short and on pipe, arrange sparse studded tube to the convection section in various industrial heating furnaces and the waste heat boiler, waste heat recovery, and it is few to enlarge heat-transfer area, and the augmentation of heat transfer effect is little.

Abroad, the minute hand finned tube of the similar present technique of employing that has, this minute hand finned tube has enlarged heat-transfer area, but the augmentation of heat transfer effect is little, and mainly be limited to oil product heat exchange and marine boiler flue gas heat exchange on the ship, be not reported and in petrochemical industry, use.

In addition, be widely used in deflection rod heat exchanger both domestic and external at present, its rod system forms independent member, with certain spacing, supports heat-transfer pipe in vertical and horizontal direction, when making fluid flow over rod, produces whirlpool, augmentation of heat transfer in the downstream, the back side of rod.But just because gapped between these rods and heat-transfer pipe, be two independent members, enlarge the effect of heat-transfer area wing rib and can not play, and this rod at each tube section place has only the 2-4 root, the point that makes it to produce whirlpool is limited, thereby the augmentation of heat transfer effect also has certain limit, and usually needs to use low thread finned tube or spiral grooved tube simultaneously, causes the cost height.

The purpose of this utility model is to provide a kind of serious fouling and coking problem that can solve high viscosity liquid better, and the dust stratification of high-temperature smoke gas and etching problem, heat transfer area can be enlarged greatly again, the high novel pin finned tube of strengthening heat-transfer effect can be obtained.And make its processing easy, and to use reliably, the life-span is long, can be widely used in the heat exchange of various high viscosity oil products in the petrochemical industry, replaces light pipe or low fin screwed pipe; Can replace the studded tube in various high temperature furnaces and the waste heat boiler.

The utility model is a kind of Needle fin tube that is used for augmentation of heat transfer, is made up of parent tube and pin wing, and the shaft-like pin wing in many long and short gardens is arranged outside parent tube, equally spacedly along circumferentially and vertically staggered or order arrange, and be the inclination angle or vertically be welded on the parent tube.

Because the rod draw ratio of the utility model Needle fin tube can be designed to optimal state according to the process application condition, and rod can be welded on the parent tube in high quality, be integrality with parent tube, basically there is not thermal contact resistance, belong to whole minute hand finned tube structure, wing fin efficiency height, and excellent wing arranges closelyer on pipe, thereby enlarged heat-transfer area greatly.Simultaneously, because it is this pin wing belongs to discrete discontinuous wing rib, can constantly destroy the boundary layer of fluid heat transferring on the parent tube, lower than continuous buttress (comprising low fin screwed pipe) liquid film thermal resistance, thereby making this heat-transfer area heat exchange efficiency height of parent tube, film coefficient of heat transfer is higher.The rod wing curves certain angle, can reach higher heat-transfer effect and the purpose that reduces resistance, increases the wing draw ratio, can obtain bigger secondary heat-transfer area, can reduce to restrain lay ratio again, makes tube bank compacter.Because the pin wing rod number of each tube section of this Needle fin tube reaches 4～9, can produce stronger eddy current effect than rod baffle, and excellent wing firmly is welded on the parent tube, belong to whole minute hand finned tube structure, heat-transfer area is big, the efficient height, played the double action of rod baffle and pin wing, it is the combination of rod baffle and minute hand wing, combine the characteristics of the two, thereby can solve the serious fouling and the coking problem of high viscosity liquid, and the dust stratification of high-temperature smoke gas and etching problem, can enlarge heat transfer area greatly again, obtain the high heat-transfer effect of strengthening.And process easyly, and to use reliably, the life-span is long.

Narrate embodiment of the present utility model in further detail below in conjunction with accompanying drawing.

Fig. 1 is the structural representation of Needle fin tube

Fig. 2 is vertical detail drawing of Needle fin tube

Fig. 3 is the circumferential arrangement schematic diagram of Needle fin tube

As Fig. 1, the utility model is by parent tube 3, and oblique pin wing 1 of stock and hour hand wing 2 are formed, and

pin wing

1 and 2 equally spacedly along circumferentially and vertically staggered or order arrange, and be the inclination angle or vertically be welded on the parent tube 3, the parent tube caliber is 25～32 millimeters.

As Fig. 2, the inclined angle alpha of the oblique pin wing 1 of stock is 30 °～60 °, and the inclined angle alpha of quarter butt pin wing 2 is 0 °,

pin wing

1 and 2 bar directly are 4～6 millimeters, and bar length is 21～36 millimeters, and the draw ratio of hour hand wing 2 is 3～5, the draw ratio of minute hand wing is 5～8, and the longitudinal pitch of pin wing is 8～16 millimeters.

As Fig. 3, each tube section and pin wing rod number are 4～9, and along circumferentially evenly distributing.

In order to investigate this enhancement heat transfer of Pin-Fin Tube effect, once done a large amount of simulated tests in laboratory, medium has adopted the diesel oil of gas and different viscosities and heavy oil etc. respectively.The heat transfer caliber be in 32 and in 25 millimeters, the inclination angle of pin wing is 30 °, 45 °, 60 °, rod pin wing diameter is 6 millimeters of φ 4～φ, long 21～36 millimeters of rod pin wing, the draw ratio of hour hand wing is 3～5, the draw ratio of minute hand wing is 5～8, and the longitudinal pitch of pin wing is 10～16 millimeters, and same tube section upper edge circumferentially uniform rod number is 6～9.Result of the test pin wing efficient can be up to 0.95, and augmentation of heat transfer can reach more than 2 times.The theoretical model parsing all conforms to result of the test with finite element analysis and numeric value analysis calculating.

Claims

1. a Needle fin tube that is used for augmentation of heat transfer is made up of parent tube and pin wing, it is characterized in that parent tube has many long and short round bar shape pin wings outward, equally spacedly along circumferentially and vertically staggered or order arrange, and be the inclination angle or vertically be welded on the parent tube.

2. Needle fin tube as claimed in claim 1, the caliber that it is characterized in that parent tube is 25～32 millimeters, the inclined angle alpha of the oblique pin wing of stock is 30 °～60 °, quarter butt pin wing inclination angle is 0 °, the bar of pin wing rod directly is 4～6 millimeters, and bar length is 21～36 millimeters, and the draw ratio of hour hand wing is 3～5, the draw ratio of minute hand wing is 5～8, and the longitudinal pitch of pin wing is 8～16 millimeters.

3. Needle fin tube as claimed in claim 1 is characterized in that the pin wing rod number of each tube section is 4～9, and along circumferentially evenly distributing.