CN109807511A - Reduce the in-service welding sleeve that hydrogen splits tendency - Google Patents

Reduce the in-service welding sleeve that hydrogen splits tendency Download PDF

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Publication number
CN109807511A
CN109807511A CN201910101163.1A CN201910101163A CN109807511A CN 109807511 A CN109807511 A CN 109807511A CN 201910101163 A CN201910101163 A CN 201910101163A CN 109807511 A CN109807511 A CN 109807511A
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China
Prior art keywords
sleeve
pipeline
welding
service
heating
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CN201910101163.1A
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Chinese (zh)
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CN109807511B (en
Inventor
张丽萍
王敬东
左存果
尹立孟
李明忠
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Chongqing University of Science and Technology
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Chongqing University of Science and Technology
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Abstract

The invention discloses a kind of in-service welding sleeves, it is formed including sleeve and heating tape, heating tape had both been used as weld preheating component, was also used as postweld heat preservation device, be used cooperatively with sleeve, by before weldering, the heat treatment of postwelding split phenomenon to reduce inevitable hydrogen in welding process;Sleeve is welded on the position for needing to repair, to prevent to reveal or reinforce pipeline, there are certain intervals between sleeve and pipeline, high-pressure inert gas is filled in gap, the power received at pipeline can not only be reduced, and the inert gas property in gap is stablized, can be avoided pipeline by extraneous corrosion, to extend pipeline life, so that the pipeline after repairing can continue to the long period of being on active service.

Description

Reduce the in-service welding sleeve that hydrogen splits tendency
Technical field
The invention belongs to pipeline welding fields, and in particular to a kind of in-service welding sleeve for reducing hydrogen and splitting tendency.
Background technique
Oil-gas pipeline during long service, inevitably corrosion failure and cause the broken of leakage and pipeline Bad, processing may cause many serious problems not in time, must add thus to the part that pipeline is weak or reveals Gu and repair, cannot stop welding for oil-gas pipeline, in addition hydrogen induced cracking (hereinafter referred to as hydrogen is split) is also to cause to weld The one of the major reasons of failure are stitched, cannot solve above-mentioned two problems very well can not reach good repairing effect.
The in-service welding procedure that the prior art provides mainly includes two kinds, is exactly outside damaged portion one is sleeve reparation Welded sleeve is come to reinforcing at piping failure, another method is exactly branch pipe welding recovery technique, is exactly before damaged section A branch is welded afterwards, and repair process carries out transport oil gas by branch, after the completion of reparation, then takes back main road, second of side Method is obviously more time-consuming, and welding fault will cause normal pipeline instead and go wrong, therefore in actual use, often with first Kind of method carries out small-scale reparation, when replacing pipeline just uses second method, but since substrate is that have fluid flowing Pipeline, and sleeve be close to tube wall, so heat loss can quickly, so there is the risk of higher burn-through.
No matter which kind of above-mentioned method is used, what hydrogen was split is all the problem of can not avoiding, and hydrogen, which splits Producing reason, to summarize Be three aspects: first is that the addition of hydrogen source, in the welding process, atmosphere, material, the protium in welding rod can welding process into Enter in weld seam;Second is that the carbon equivalent of substrate itself, cooling velocity cause;Third is that welding stress caused by welding procedure, will be reduced The influence that hydrogen is split just needs to solve any one in above three aspect.
The prior art reduces cooling velocity frequently with the methods of low-hydrogen electrode, temper bead/ annealing bead technique, mid-frequency induction heating And hydrogen source intake, to reduce the influence that hydrogen is split;Application No. is 201810360208.2 Chinese invention patents, propose one The two methods of the prior art are integrated, are subtracted by building branch pipe again by the in-service welding method of kind gas pipeline, the invention Flow velocity in small supervisor, to reduce cooling velocity, remaining step is similar to the prior art, but this method needs to build branch again Pipe increases operating procedure, and since pipeline fluid is flowing, so heat loss is still very serious.
Summary of the invention
The object of the present invention is to provide a kind of in-service welding sleeves, can reduce burn-through while reducing hydrogen and splitting tendency Probability, realize better using effect.
To achieve the above object, the technical scheme is that
A kind of in-service welding sleeve for reducing hydrogen and splitting tendency, including sleeve, heating tape, the sleeve are sleeved on pipeline, by Multiple sleeve valves are welded, and are provided with chamfer bevel on the side that sleeve valve contacts with each other, and welding is facilitated to operate, on sleeve lining It is additionally provided with groove, for reducing the internal stress in welding process, high pressure valve is additionally provided on sleeve, for being filled with high pressure gas Body;The heating tape is divided into two layers, is heating layer, heat insulation layer respectively, and what is filled in heating layer is the heat transfer medium of liquid, insulation What is filled in layer is insulation medium, can reduce scattering and disappearing for heat.
Further, the cross sectional shape of the groove is arc.
Further, the heating tape is as weld preheating in use, high-temperature heating band two sides are fixed on, on reduction pipeline Thermal stress.
Further, the internal diameter of the annulus is less than sleeve diameter, and annulus outer diameter is greater than sleeve diameter and is less than outside sleeve Diameter.
The present invention can at least reach it is following the utility model has the advantages that
(1) there are certain gaps between sleeve and pipeline, and welded sleeve Shi Buyu pipeline directly contacts, therefore heat loss is more It is few.
(2) it is filled among gap using pressurized inert gas, and awards one inward force of pipeline, reduce piping failure The power that place is subject to, while condition relatively stable in gap reduce the corrosion of pipeline from outside to inside, and extend pipeline uses the longevity Life.
(3) heating tape can play the role of weld preheating, postweld heat preservation, further decrease, the tendency that hydrogen is split.
(4) heating tape uses the heat transfer medium of liquid, can not only more be bonded with sleeve surface, while can guarantee to add The consistency of hot-face temperature.
(5) annulus can reduce welding workload, while use as run-on tab.
(6) groove can reduce machining stress.
Detailed description of the invention
The Figure of description for constituting the application a part is used to provide further understanding of the present invention, signal of the invention Examples and descriptions thereof are used to explain the present invention for property, does not constitute improper limitations of the present invention.
In attached drawing:
Fig. 1 diagrammatically illustrates the cross-sectional view of middle sleeve of the present invention;
Fig. 2 diagrammatically illustrates the side view of middle sleeve of the present invention;
Fig. 3 diagrammatically illustrates the structural schematic diagram of heating tape in the present invention;
Wherein, the above drawings include the following reference numerals:
11- sleeve valve, 12- groove, 13- weld seam, 14- high pressure valve, 15- annulus, 21- heating layer, 22- heat insulation layer, 3- pipeline.
Specific embodiment
It is noted that following detailed description is all illustrative, it is intended to provide further instruction to the application.Unless another It indicates, all technical and scientific terms used herein has usually manages with the application person of an ordinary skill in the technical field The identical meanings of solution.
It should be noted that term used herein above is merely to describe specific embodiment, and be not intended to restricted root According to the illustrative embodiments of the application.As used herein, unless the context clearly indicates otherwise, otherwise singular Also it is intended to include plural form, additionally, it should be understood that, when in the present specification using term "comprising" and/or " packet Include " when, indicate existing characteristics, step, operation, device, component and/or their combination.
In addition, term " includes " and " having " and their any deformation, it is intended that covering non-exclusive includes example Such as, the process, method, system, product or equipment for containing a series of steps or units those of are not necessarily limited to be clearly listed Step or unit, but may include being not clearly listed or intrinsic for these process, methods, product or equipment other Step or unit.
For ease of description, spatially relative term can be used herein, as " ... on ", " ... top ", " ... upper surface ", " above " etc., for describing such as a device shown in the figure or feature and other devices or spy The spatial relation of sign.It should be understood that spatially relative term is intended to comprising the orientation in addition to device described in figure Except different direction in use or operation.
Embodiment
It is a kind of in-service welding sleeve, including sleeve and heating tape composition, heating tape and sleeve as shown in Fig. 1 ~ 3 Be used cooperatively, both as one of weld preheating component and postweld heat preservation device, by before weldering, the heat treatment of postwelding reduces Inevitable hydrogen splits phenomenon in welding process;Sleeve is welded on the position for needing to repair, to prevent leakage or reinforced pipe Road is filled with high-pressure inert gas, can not only reduce 3 place of pipeline there are certain interval between sleeve and pipeline 3 in gap The power received, and the inert gas property in gap is stablized, and can be avoided pipeline 3 by extraneous corrosion, to extend pipeline 3 Service life, so that the pipeline 3 after repairing can continue to the long period of being on active service.
Sleeve is synthesized by the welding of sleeve valve 11, according to the difference of 3 caliber of pipeline, the not just two panels of sleeve valve 11, and tubule The two panels sleeve valve 11 of pipeline 3 of diameter, the multiple sleeve valves 11 of pipeline of Large Diameter Pipeline, so convenient transportation and storage, The present embodiment is illustrated by taking two panels sleeve valve 11 as an example, two sleeve valves 11 is synthesized an annulars when use, such as Fig. 1 institute Showing, is then welded, the edge of sleeve valve 11 processes inclined ramp in advance, when two sleeve valves 11 synthesize annular, Two inclined ramp bottoms contact to form V-groove, facilitate welding, the internal diameter of sleeve is greater than caliber, so in welded sleeve valve It when 11, is not contacted with pipeline 3, pipeline 3 will not be damaged to burn-through when welding, and due to not contacting with pipeline 3, so Heat leakage is less, can reach preferable welding quality;In addition groove 12, the section shape of groove 12 are additionally provided on sleeve lining Shape is arc, and compared to smooth inner wall, the inner wall with groove 12 can absorb the stress generated when part is expanded with heat and contract with cold, is reduced The internal stress of material, and the stress that smooth inner wall is generated when expanding with heat and contract with cold can stay in the material, become internal stress, internal stress is got over The defects of being also more easy to appear crackle greatly.
The end face of left and right two in sleeve orientation shown in Fig. 2 is become into left side and right side, left and right end face and pipeline 3 Connection, connection type are welding, a high pressure valve 14 are additionally provided on sleeve, to the gap of sleeve and pipeline 3 after welding completion In fill high-pressure inert gas, the pressure of high-pressure inert gas is identical as the transport pressure of fluid in pipeline 3, can give pipeline 3 one A inward pressure offsets the pressure of pipeline 3 with fluid in pipeline 3, to reduce the power of the receiving of pipeline 3, and then avoids Crackle on pipeline 3 further increases, and the property of inert gas is relatively stable, and the fluid transported in the pipeline 3 is gas It will not react, and since the weak part of pipeline 3 is wrapped up by sleeve, especially 3 outer wall of pipeline is also located at inert gas Atmosphere, not will receive the influence of external environment, will not continue to be corroded by external environment, pipeline 3 is enable to stablize use For more time.
Gap is larger between casing and pipeline, if all being filled up with welding, needs to weld more multi-pass, it is important that this The release of sample welding heat is too many, and the range of heat affected area can be made to expand, and normal pipeline section generates thermal stress, for this purpose, can cover An annulus 15 is respectively placed in cylinder or so two end faces, and the internal diameter of annulus 15 is less than the internal diameter of sleeve, and the outer diameter of annulus 15 is less than set Cylinder outer diameter is greater than sleeve diameter, and annulus 15 forms ladder close to the left and right end face of sleeve therewith, in welding, it is only necessary to will justify Ring 15 and pipeline, sleeve weld get up can, can equally guarantee air-tightness, but greatly reduce welding workload, And annulus 15 is also used as run-on tab use, improves welding quality.
It needs first to heat the fluid in pipeline 3 before welded sleeve, to reduce heat leakage when welding, such as scheme Shown in 3, heating tape is divided into two layers, is heating layer 21, heat insulation layer 22 respectively, that fill in heating layer 21 is heat transfer Jie of liquid Matter heats heating layer 21 close to 13 place face of weld seam when use to weld seam 13, the heat transfer medium in heating layer 21 with plus Thermal connection, heats heat transfer medium by heating device, what is filled in heat insulation layer 22 is insulation medium, can be subtracted Small heat scatters and disappears, since heating layer 21 is the heat transfer medium of liquid, so can preferably be bonded with weld seam 13, because of weld seam 13 shape is not necessarily fully horizontal, reaches better heating effect with this.
The prior art often only with high-temperature heating band together, heats the fluid that will flow through welding position, passes through Actual use discovery, only will lead to be heated with a high-temperature heating band can suddenly rise with 3 temperature of pipeline wound, with week The temperature difference in bustle pipe road 3 is larger, can generate biggish thermal stress, is unfavorable for the long-time service of pipeline 3, and therefore, the present invention is in height Warm heating tape two sides are arranged a plurality of low-temperature heat band and form a temperature gradient slowly risen, to reduce thermal stress;In addition, Low-temperature heat band is also used in the heat preservation of weld seam 13, after welding terminates, is kept the temperature to welding position, post weld heat treatment can Welding stress after effectively reducing welding mitigates the phenomenon that hydrogen is split.
Process for using of the invention is as follows:
1) two sleeve valves are welded into a sleeve by welded sleeve, are welded using downhand welding or overhead welding position, when avoiding burning Molten drop drips on pipeline, due to sleeve diameter be greater than pipeline caliber, so welding when, not with tube contacts, therefore Heat leakage is less;Since the step only forms sleeve weld, so sleeve still can move on pipeline, conveniently again Adjusting position;
2) low-temperature heat band is fixed outside sleeve, and weld seam is kept the temperature;
3) weld preheating, the setting close to welding position are heated at high temperature band, and low-temperature heat band is arranged in high-temperature heating band two sides, to pipe Fluid in road is heated;
4) one annulus of each placement is placed in the end face of the left and right of sleeve two, annulus is welded together with pipeline, casing respectively, To which sleeve be fixed;
5) low-temperature heat band is set in position while welding, weld seam is kept the temperature.
Embodiment as one preferred, the temperature of the postweld heat preservation are 280 DEG C ± 10 DEG C, and soaking time is 2 hours.
Embodiment as one preferred, the liquid heat transfer material are high temperature heat conductive oil.
In the present embodiment, the high pressure valve, liquid heat transfer medium, high-temperature heating band, heat-barrier material, heating device are The mature prior art, therefore do not elaborate.

Claims (5)

1. a kind of in-service welding sleeve for reducing hydrogen and splitting tendency, it is characterised in that: including sleeve, heating tape, the sleeve set It on pipeline, is welded by multiple sleeve valves, is provided with chamfer bevel on the side that sleeve valve contacts with each other, welding is facilitated to grasp Make, be additionally provided with groove on sleeve lining, for reducing the internal stress in welding process, high pressure valve is additionally provided on sleeve, is used In being filled with high pressure gas;The heating tape is divided into two layers, is heating layer, heat insulation layer respectively, what is filled in heating layer is liquid Heat transfer medium, what is filled in heat insulation layer is insulation medium, can reduce scattering and disappearing for heat.
2. a kind of in-service welding sleeve for reducing hydrogen and splitting tendency according to claim 1, it is characterised in that: the groove Cross sectional shape be arc.
3. a kind of in-service welding sleeve for reducing hydrogen and splitting tendency according to claim 1, it is characterised in that: the heating Band is used as weld preheating in use, being fixed on high-temperature heating band two sides, thermal stress when reducing welding on pipeline.
4. a kind of in-service welding sleeve for reducing hydrogen and splitting tendency according to claim 1, it is characterised in that: on pipeline also It is set with annulus, annulus is located at sleeve two sides, welds together with sleeve, pipeline.
5. a kind of in-service welding sleeve for reducing hydrogen and splitting tendency according to claim 4, it is characterised in that: the annulus Internal diameter be less than sleeve diameter, annulus outer diameter be greater than sleeve diameter and be less than sleeve outer diameter.
CN201910101163.1A 2019-01-31 2019-01-31 Sleeve for in-service welding for reducing hydrogen cracking tendency Expired - Fee Related CN109807511B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114570885A (en) * 2022-03-15 2022-06-03 王泽泽 Casting deformation heat adjustment mold

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Publication number Priority date Publication date Assignee Title
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