CN106321200A

CN106321200A - Main body pipe for SCR urea pipe and SCR urea pipe

Info

Publication number: CN106321200A
Application number: CN201610736736.4A
Authority: CN
Inventors: 高明; 李宏杰; 李庆刚
Original assignee: CHANGSHUN YADA AUTOMOBILE COMPONENTS AND PARTS MANUFACTURING Co Ltd
Current assignee: CHANGSHUN YADA AUTOMOBILE COMPONENTS AND PARTS MANUFACTURING Co Ltd
Priority date: 2016-08-29
Filing date: 2016-08-29
Publication date: 2017-01-11
Also published as: WO2018040149A1

Abstract

The invention provides a main body pipe for an SCR urea pipe and the SCR urea pipe. The main body pipe comprise a core pipe, a heating layer and a micro-foaming insulating layer, wherein the heating layer is arranged at the outer side of the core pipe in a wrapping manner, and the micro-foaming insulating layer is arranged at the outer side of the heating layer in a wrapping manner. A base body of the micro-foaming insulating layer is thermoplastic elastomer. The micro-foaming insulating layer is a micro-foaming insulating layer obtained through secondary extrusion molding conducted on the core pipe. The heating layer of the main body pipe is an electric heating wire. The electric heating wire further extends and is wound on a joint. The main body pipe is sleeved with an appearance layer. The joint and the appearance layer are subjected to rubber coating treatment. The SCR urea pipe is attractive in appearance, uniform in power distribution, small in number of circuit connection points, low in failure risk, good in thermal insulation performance, low in energy consumption, resistant to water and dust and uniform in heat conduction.

Description

A kind of SCR urea tube main body pipeline and SCR urea tube

Technical field

The invention belongs to motor exhaust post-processing technology field, be specifically related to a kind of in diesel automobile exhaust post processing SCR (SCR) system on SCR urea tube main body pipeline and SCR urea tube.

Background technology

Present stage, along with the requirement of Environmental protection is more and more higher, commercial car is mainly manifested in automobile is arranged Putting in the requirement of regulation, forced to use Europe IV discharge, the strictest Europe V discharge standard will give reality in 3 years Execute.For realizing above-mentioned emission request, current home and abroad diesel car the most commonly used SCR(Selective Catalyst Reduction) technology carries out emission aftertreatment, utilizes aqueous solution of urea to be ejected in diesel exhaust gas as reducing agent, useless Under the effect of temperature and air-flow, carbamide discharges ammonia (NH through pyrolysis and hydrolysis₃), and at uniform temperature and catalyst Under effect, NOx is reduced to nitrogen (N₂) and water (H₂O), to reduce the purpose of NOx discharge.

And can crystallize during urea liquid-11 DEG C under normal pressure, for ensureing that diesel engine can normally make in cold season With, it is necessary to urea pipe is heated, to ensure urea liquid proper flow in a liquid-like manner, is wound with outside usual urea tube Resistance wire, is heated urea tube by resistance wire.But what the urea pipe in existing product had does not has heat-insulation layer, only passes through Increasing electrical power and meet defrosting requirement, shortcoming is indirectly to increase energy consumption of vehicles；Outer layer is simply carried out by some urea pipes The forms such as general extrusion insulation and linen-cotton braid insulation, shortcoming is all not have good heat insulation effect, and heat insulation effect is not Substantially, heat-insulation layer internal-external temperature difference only has 1 ~ 2 DEG C；Employing EPDM rubber foaming is currently also had to be incubated, but the setting of this foaming Standby investment is very big, can not well adhere to body core pipe and be connected, the too fat to move and post-production that seems the most greatly of simultaneously foaming Technique is the most difficult.The heat that above-mentioned urea pipe all can not make heating wire send can farthest be applied on body, makes In pipe, the liquid of frost melts as soon as possible.

On automobile, the SCR heated pressure pipe product in SCR system is various informative, and general employing fitting end is Plastic pipe clip 1 carries out outward appearance process, heating wire 2-1 be wound around after body with adhesive tape 3 fixed, the heater wire later stage of end-fitting Mate, product junction point 4-1 is more, carry out insulation etc. without heat-insulation layer, sees Fig. 1, Fig. 2.During the use on vehicle of this kind of structure Have a following disadvantage:

A, outward appearance are poor, simultaneously because there is the existence of protrusion on pipe clamp, easily causes other product adjacent with this pipe and produce Abrasion, the inefficacy so that other products are worn；

B, the later stage coupling of pipe joint heater wire, be not easily formed series circuit, and electric thermal power distribution simultaneously deviation easily occurs, makes The defrosting efficiency becoming each position differs；

C, heating wire junction point more, make the electric fault risk increase of product more than at least 25%；

D, product do not have external thermal insulation, cause thermal loss relatively big, indirectly add oil consumption, are unfavorable for reducing vehicle exhaust Discharge；

E, due to end use pipe clamp process, there is no sealing, easily make rainwater be very easy to enter interiors of products, make product deposit In higher electric leakage risk；

The heat being transmitted on body after the heating of f, resistive conductor is uneven.

Therefore the SCR system pressure piping in vehicle exhaust post processing need one have outward appearance good, power consumption less, fault wind Relatively low, the product of water proof and dust proof in danger.

Summary of the invention

In order to solve above-mentioned the deficiencies in the prior art, it is an object of the invention to the SCR system for vehicle maintenance service and carry For a kind of efficient, stable, SCR urea tube main body pipeline of the most low-risk a kind of new construction and SCR urea tube.

The technical problem to be solved is achieved by the following technical programs:

A kind of SCR urea tube main body pipeline, it is characterised in that include core pipe, be coated on the zone of heating outside described core pipe and It is coated on the fretting map heat-insulation layer outside described zone of heating.

Further, the matrix of described fretting map heat-insulation layer is thermoplastic elastomer (TPE).

Further, described fretting map heat-insulation layer is the fretting map heat-insulation layer carrying out second time extrusion molding on core pipe.

Further, being provided with heat-conducting layer between described zone of heating and fretting map heat-insulation layer, described heat-conducting layer is aluminium foil.

The present invention also provides for a kind of SCR urea tube, and it includes above-mentioned main body pipeline and the core pipe with described main body pipeline The joint connected.

Further, the zone of heating of described main body pipeline is heating wire；Described heating wire also extends and is wrapped in described joint On.

Further, described heating wire one end is connected with external power connecting line, and the other end carries out closing connection, forms string Connection circuit.

Further, described heating wire all uses double with the junction point of electric power connection line and described heating wire closing junction point Wall heat-shrink tube carries out insulative water-proof process.

Further, described main body pipeline is arranged with outward appearance layer；Described joint and outward appearance layer carry out encapsulated process.

There is advantages that

(1) the Microcellular foam extrusion contrast original structure energy consumption of body reduces by more than 20%；This thermal-insulating scheme heat insulation effect is obvious, protects Temperature layer internal-external temperature difference has 15 ~ 18 DEG C, it is simple to technique realizes；Microcellular foam extrusion is easy to large batch of production, reaches 15m-20m/ min；(2) contrast of the heating power on joint original structure is stable, and fluctuation is less than 1%；(3) product electrical equipment junction point fault rate pair More than 25% is reduced than original structure；(4) make profile more attractive in appearance due to the encapsulated process of fitting end, simultaneously work as waterproof Effect, particularly as follows: the 500mm degree of depth of can soaking, 24h, simultaneously energising 24h properties of product be not any change, do not have water to enter into yet Tubular body.

Accompanying drawing explanation

Fig. 1 is existing structure schematic diagram；

Fig. 2 is existing structure circuit theory diagrams, and wherein R1 is joint 1 resistance, and R2 is body resistance 1, and R3 is body resistance 2, R4 For joint 2 resistance；

Fig. 3 is the pipe structure schematic diagram that the present invention is embodied as；

Fig. 4 is the intermediateness that the present invention is embodied as the assembling process of structure；

Fig. 5 is the circuit catenation principle figure that the present invention is embodied as in structure, and wherein R1 is body resistance 1, and R2 is body resistance 2；

Fig. 6 is SCR urea tube assembly state diagram of the present invention.

In figure: 1, plastic pipe clip, 2,2-1 heating wire, 3, adhesive tape, 4,4-1 junction point, 5, main body pipeline, 6, core pipe, 7, micro- Insulating foam layer, 8, heat-conducting layer, 9, joint, 10, outward appearance layer, 11, encapsulated portion.

Detailed description of the invention

The present invention will be described in detail with embodiment below in conjunction with the accompanying drawings.

Embodiment 1

As it is shown on figure 3, present embodiments provide the main body pipeline 5 of a kind of SCR urea tube, it includes core pipe the most successively 6, zone of heating and fretting map heat-insulation layer 7.

Described core pipe 6 is for transport urea solution, preferably nylon tube, it is highly preferred that be multilamellar nylon tube；Described heating Layer preferably but is not limited to the heating wire 2 that Double helix is wrapped in outside core pipe 6, can the uniform urea liquid in heating core pipe 6, prevent Only it freezes.

The heat that described main body pipeline 5 first has to make heating wire 2 send can farthest be applied on core pipe 6, makes pipe The liquid of interior frost melts as soon as possible, and this is always an extremely difficult problem.The more main body pipeline 5 of existing market is tied Structure does not has heat-insulation layer, only increases electrical power and meets defrosting requirement, the most indirectly increases energy consumption of vehicles simultaneously；Also increase is had to protect Temperature layer is to realize heat insulation effect, but mainly carries out the forms such as general extrusion insulation and linen-cotton braid insulation at outer layer, In terms of result of the test, all not having good heat insulation effect, i.e. heat insulation effect inconspicuous, heat-insulation layer internal-external temperature difference only has 1 ~ 2 DEG C；Also There is use EPDM rubber foaming to be incubated, but the equipment investment of this foaming is very big, can not carry out the most attached with core pipe Connection, foam seems the most greatly too fat to move and post-production is the most difficult simultaneously.The present inventor attempts the various foaming side of various material The test of formula, preferably goes out the fretting map scheme with thermoplastic elastomer (TPE) as matrix.Described fretting map heat-insulation layer 7 preferably but does not limits For carrying out the fretting map heat-insulation layer of second time extrusion molding on core pipe, i.e. by being extruded into core pipe, then at core for the first time Carry out second time on pipe and be extruded into fretting map heat-insulation layer；Described fretting map heat-insulation layer, preferably with thermoplastic elastomer (TPE) as matrix Fretting map heat-insulation layer；Described thermoplastic elastomer (TPE) is preferably but not limited to TPV；Described thermoplastic elastomer (TPE) can also is that through changing Property process；The thickness of described fretting map heat-insulation layer is preferably but not limited to 2-3mm, it is highly preferred that thickness is 2.5mm；This insulation Scheme heat insulation effect is obvious, and heat-insulation layer internal-external temperature difference has 15 ~ 18 DEG C, it is simple to technique realizes；Microcellular foam extrusion is easy to large batch of Produce, reach 15m ~ 20m/min.

Make further improvements ground, between described zone of heating and fretting map heat-insulation layer 7, be provided with heat-conducting layer 8.In order to preferably Being distributed in the even heat of heating wire 2 on core pipe 6 body, described heat-conducting layer 8 is preferably the aluminium foil that heat conduction efficiency is higher, It is highly preferred that described aluminium foil is wrapped on described zone of heating by single-screw mode.

This structure design of described main body pipeline 5, effectively uses the heat that heating wire 2 produces, reduces The energy consumption of car load, reduces the energy consumption of at least 20% than existing structure, indirectly reduces discharge.

Embodiment 2

Such as Fig. 4, shown in 6, present embodiments provide a kind of SCR urea tube, it include the main body pipeline 5 described in embodiment 1 and with The joint 9 that the core pipe of described main body pipeline 5 connects；Described joint 9 is preferably by laser welding or cold pressing and be connected to core pipe 6 body On, but it is not limited to this；Described joint 9 and core pipe are fixing be connected after, described heating wire 2 also extends and is wrapped on described joint 9, So that jointing is carried out heat treated.

As in figure 2 it is shown, be existing structure circuit theory diagrams, under this state, production technology calculates and manufactures all Cumbersome, when manufacturing especially, material kind is more, easily obscures and misuses, and causes properties of product to decline；And in a period of time The most this misuse, mixed phenomenon happens occasionally.In order to overcome drawbacks described above, heating wire 2 one end of the present invention is connected with external power source Line connects, and the other end carries out closing connection, forms series circuit as shown in Figure 5, and production management and product quality are the most significantly Promoting, the most this structural principle makes number of nodes decrease 2, and fault rate reduces 40% the most accordingly.

Further, described heating wire 2 is closed junction point 4 all adopt with junction point 4 and the described heating wire 2 of electric power connection line Insulative water-proof process is carried out, the good waterproof performance of product with the double wall heat draw.

Make further improvements ground, described main body pipeline 5 is arranged with outward appearance layer 10, preferably corrugated tube.Traditional product Marine glue is noted after being fastened by pipe clamp inside pipe clamp in fitting end position, and the disadvantage of this kind of mode is appearance poor, projection, rib The clearly demarcated cusp in angle easily makes other products produce abrasion, and glue note not only note is discontented, and water proofing property is the poorest, heat insulating ability is poor simultaneously, produces During more bother, operation is many, artificial put into the most, relatively costly.In order to overcome drawbacks described above, the joint of the present invention 9 with Outward appearance layer 10 carries out encapsulated process, forms encapsulated portion 11, makes product design more attractive in appearance, simultaneously works as waterproof effect, through surveying Examination, the 500mm degree of depth of can soaking, 24h, simultaneously energising 24h properties of product are not any change, and do not have water to enter into tubular body yet, Primary tube clamping structure can not be waterproof.

After tested, compared with existing structure, the SCR urea tube energy consumption that the present embodiment provides reduces by more than 20%；This insulation side Case heat insulation effect is obvious, and heat-insulation layer internal-external temperature difference has 15 ~ 18 DEG C, it is simple to technique realizes；Microcellular foam extrusion is easy to large batch of life Produce, reach 15m ~ 20m/min；Heating power contrast original structure on joint is stable, and fluctuation is less than 1%；Connection point node Quantity decreases 2, uses the double wall heat draw to carry out insulative water-proof process simultaneously, fault rate contrast original structure reduce by 25% with On；Owing to the encapsulated process of fitting end makes profile more attractive in appearance, simultaneously work as waterproof effect, particularly as follows: the 500mm that can soak The degree of depth, 24h, simultaneously energising 24h properties of product are not any change, and do not have water to enter into tubular body yet.

Embodiment 3

The preparation method of a kind of SCR urea tube, specifically includes following steps:

(1) it is wound around heating wire at the outer Double helix of core pipe, single-screw is wound around aluminium foil and on core pipe, carries out second time extruded shape Become there is the fretting map heat-insulation layer of heat-insulating property, it is thus achieved that main body pipeline；

(2) according to process length, main body pipeline carries out cutting a long process, and the fretting map layer cutting that end is coated with is opened, the most again Get rid of inner foil and the multilayer core pipe being cut out part, outside main body pipeline, then overlap corrugated tube, finally will be even Joint laser welding or the mode connected of colding pressing are connected on core pipe body body；

(3) being attached with internal heating wire by corresponding external power supply connecting line according to product needed, the other end is carried out simultaneously Heating wire is closed and is connected, and forms the series circuit of a standard, is then carried out at insulative water-proof by the junction point double wall heat draw Reason；After completing, heating wire is wound on jointing；

(4) the above-mentioned semi-finished product jointing end completed is placed in injection mold, by blank area and bellows section Carry out encapsulated process.

The less investment simple, artificial of this preparation method technique, low cost, production management and product quality be increased dramatically, And compared with existing structure, the SCR urea tube energy consumption that the present embodiment prepares reduces by more than 20%；This thermal-insulating scheme heat insulation effect Substantially, heat-insulation layer internal-external temperature difference has 15 ~ 18 DEG C, it is simple to technique realizes；Microcellular foam extrusion is easy to large batch of production, reach 15m ~ 20m/min；Heating power contrast original structure on joint is stable, and fluctuation is less than 1%；Connection point number of nodes decreases 2 Individual, use the double wall heat draw to carry out insulative water-proof process simultaneously, fault rate contrast original structure reduces by more than 25%；Due to joint The encapsulated process of end makes profile more attractive in appearance, simultaneously works as waterproof effect, particularly as follows: the 500mm degree of depth of can soaking, 24h, with Shi Tong electricity 24h properties of product are not any change, and do not have water to enter into tubular body yet.

Embodiment described above only have expressed embodiments of the present invention, and it describes more concrete and detailed, but can not Therefore the restriction to the scope of the claims of the present invention it is interpreted as, as long as using the skill that the form of equivalent or equivalent transformation is obtained Art scheme, all should fall within the scope and spirit of the invention.

Claims

1. a SCR urea tube main body pipeline, it is characterised in that include core pipe, be coated on the zone of heating outside described core pipe And it is coated on the fretting map heat-insulation layer outside described zone of heating.

SCR urea tube main body pipeline the most according to claim 1, it is characterised in that the base of described fretting map heat-insulation layer Body is thermoplastic elastomer (TPE).

SCR urea tube main body pipeline the most according to claim 1 and 2, it is characterised in that described fretting map heat-insulation layer is Core pipe carries out the fretting map heat-insulation layer of second time extrusion molding.

SCR urea tube main body pipeline the most according to claim 1, it is characterised in that described zone of heating and fretting map are protected It is provided with heat-conducting layer between temperature layer.

SCR urea tube main body pipeline the most according to claim 4, it is characterised in that described heat-conducting layer is aluminium foil.

6. a SCR urea tube, it is characterised in that include the main body pipeline as described in claim 1 to 5 is arbitrary and with as described in master The joint that the core pipe of body pipeline connects.

SCR urea tube the most according to claim 6, it is characterised in that the zone of heating of described main body pipeline is heating wire；Institute State heating wire also to extend and be wrapped on described joint.

SCR urea tube the most according to claim 7, it is characterised in that described heating wire one end and external power connecting line Connecting, the other end carries out closing connection, forms series circuit.

SCR urea tube the most according to claim 8, it is characterised in that described heating wire and the junction point of electric power connection line Closing junction point with described heating wire all uses the double wall heat draw to carry out insulative water-proof process.

SCR urea tube the most according to claim 6, it is characterised in that be arranged with outward appearance layer on described main body pipeline；Institute State joint and carry out encapsulated process with outward appearance layer.