CN107191743A - A kind of steel pipe two-part exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method - Google Patents
A kind of steel pipe two-part exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method Download PDFInfo
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- CN107191743A CN107191743A CN201710583684.6A CN201710583684A CN107191743A CN 107191743 A CN107191743 A CN 107191743A CN 201710583684 A CN201710583684 A CN 201710583684A CN 107191743 A CN107191743 A CN 107191743A
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- Prior art keywords
- mouth
- head
- dead
- short tube
- corrosion
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L58/00—Protection of pipes or pipe fittings against corrosion or incrustation
- F16L58/02—Protection of pipes or pipe fittings against corrosion or incrustation by means of internal or external coatings
- F16L58/04—Coatings characterised by the materials used
- F16L58/08—Coatings characterised by the materials used by metal
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/16—Devices for covering leaks in pipes or hoses, e.g. hose-menders
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L58/00—Protection of pipes or pipe fittings against corrosion or incrustation
- F16L58/02—Protection of pipes or pipe fittings against corrosion or incrustation by means of internal or external coatings
- F16L58/04—Coatings characterised by the materials used
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Arc Welding In General (AREA)
Abstract
Exempt from the dead mouth of interior corrosion-resistanting interpolating port the present invention relates to a kind of steel pipe two-part and connect head method.Comprise the following steps：(1) head short tube procedure of processing is connected：(1) two sections of steel pipe short tubes are intercepted by the steel pipe specification of design code；(2) built-up welder pipe end inwall circumference built-up welding stainless steel material is used；(3) the pre- repaired mouth layer of lathe process corrosion resistant alloy and short tube two ends groove；(2) the dead mouth of field pipes connects head step：The non-heap welding end of short tube is connected with two ends pipeline welding respectively；Butt welding mouth inwall is carried out after interior corrosion-resistanting interpolating port processing respectively, and dead mouth weld seam is welded using with pre- repaired mouth built-up welding identical wlding.Beneficial effect is：The present invention is that can be achieved to exempt the dead intraoral corrosion-resistanting interpolating port of steel pipe by two sections of pre- repaired mouth built-up welding short tubes, solve corrosion-resistanting interpolating port technical bottleneck in the dead mouth weld bond of pipeline, simplify the dead mouth of internal coat pipeline and connect head process, reduce the dead mouth of interior corrosion-resistant steel pipeline and connect head construction cost.
Description
Technical field
The present invention relates to a kind of steel pipe field, more particularly to a kind of steel pipe two-part exempts from the dead mouth of interior corrosion-resistanting interpolating port
Connect head method.
Background technology
To avoid pumped (conveying) medium to the corrosion of steel pipe, it is necessary to carry out batch production preservative treatment to steel pipe inner wall, due to
Pipeline welding heat input can cause the destruction of weld bond region inner anticorrosioning coating, be needed after Site Welding construction by artificial or equipment
Butt welding mouth inwall carries out preservative treatment inside into pipeline, and this process is corrosion-resistanting interpolating port in weld bond；Equipment or people can not be passed through
Work carries out the pipe welding port of interior corrosion-resistanting interpolating port operation " the dead mouth of pipeline "；
By pipe fittings such as elbow, threeway or short tubes, or the process that two segment pipes are welded together is " dead mouth connects
Head "；Weld seam is carried out in interior corrosion-resistanting interpolating port operation, dead mouth weld bond because unsuitable equipment can enter pipeline dead oral area position
Wall turns into interior corrosion-resistant blind area；
Pass through the prefabrication such as surfacing in the built-up welding of pipe end stainless steel, stainless steel short tube pipe end liner or nickel base powder
Technique, exempting interior anti-corrosion after pipeline welding includes the method for process, cries pipeline pre- jointing method.
Patent of invention 201510042589.6 discloses one kind《Jointing method is exempted from long distance pipeline closing connection built-up welding》, the party
Method is more than three sections of pipe nipples of dead mouth length in reserve by prefabricated overall length, wherein being placed in the dead mouth pipe nipple two ends inner wall overlaying of centre not
Rust steel layer, then does interior preservative treatment again；Company's head pipe nipple one end inner wall overlaying stainless steel layer of two ends pipeline is connected, processing connects head
The non-built-up welding one end of pipe nipple, makes the total length of three sections of pipe nipples identical (allowance weld gap) with reserving dead mouth length, then right respectively
Even the non-heap welding end of head pipe nipple and two segment pipes are welded to connect and corrosion-resistanting interpolating port is handled in being carried out to weld seam, finally by dead mouth pipe nipple with
Even head pipe nipple heap welding end is welded together, and stainless steel layer and the inner anticorrosioning coating of the advance built-up welding of weld bond inwall are formed continuously
Interior anticorrosive coat, realizes the purpose for exempting from internal joint patch.
Foregoing invention is using three sections of prefabricated pipe nipples, and joint connection in site has a 4 road weld seams, wherein twice stainless steel weld joint, not only
Construction efficiency is reduced, the company's of also add head construction cost.
The content of the invention
The purpose of the present invention is exempted from interior aiming at the drawbacks described above that prior art is present there is provided a kind of steel pipe two-part
The dead mouth of corrosion-resistanting interpolating port connects head method, and this method connects head short tube by two sections of pre- repaired mouths of stainless steel of prefabrication, during site operation only
It need to process or the dead mouth length of preserved pipeline and even head assembly equal length (allowance weld gap), respectively weld two sections of company's head short tubes
Be connected on two sections of internal coat pipelines, in weld bond corrosion-resistanting interpolating port processing after, only need 1 road stainless steel weld joint, you can by it is prefabricated not
The steel overlay cladding that becomes rusty ensures the continuous of pipeline internal corrosion layer, realizes that pipe welding port exempts from the purpose of internal joint patch.
A kind of steel pipe two-part that the present invention is mentioned exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method, comprises the following steps：
(1) head short tube procedure of processing is connected：
(1) it is short as first company's head short tube (a), the second company by steel pipe specification two sections of steel pipe short tubes of interception of design code
Manage (b), stub length is more than 1.5D；
(2) head short tube (a) and second is connected first using built-up welder in TIG steel pipes and connects the pipe end inwall circle of head short tube (b)
All built-up welding stainless steel materials, built-up welding layer depth is not less than 80mm；Overlay cladding thickness is not less than 1.5mm；
(3) the pre- repaired mouth layer (a3) of lathe process corrosion resistant alloy and short tube two ends groove (a4)；
(2) the dead mouth of field pipes connects head step：
(1) dead mouth one end therein of live process pipeline (c), makes to reserve dead mouth length and the length phase of two sections of company's head short tubes
Together；
(2) connect head short tube (a) and second by first respectively and connect non-heap welding end and two ends pipeline (c) welding of head short tube (b)
Connection；
(3) butt welding mouth inwall is carried out after interior corrosion-resistanting interpolating port processing respectively, is welded using with pre- repaired mouth built-up welding identical wlding
Dead mouth weld seam；
(4) complete.
Above-mentioned first, which connects head short tube (a), includes the pre- repaired mouth layer (a3) of base tube (a1), interior anticorrosive coat (a2), corrosion resistant alloy, slope
Mouth (a4), the inner chamber of the base tube (a1) is provided with the pre- repaired mouth layer (a3) of corrosion resistant alloy, in the pre- repaired mouth layer (a3) of corrosion resistant alloy and base
Interior anticorrosive coat (a2) is provided between pipe (a1), groove (a4) is provided with the end of base tube (a1).
Above-mentioned first connects the company's of being welded as head weld seam (d) between head short tube (a) and pipeline (c).
Above-mentioned first connects between head short tube (a) and second company's head short tube (b) for the dead mouth weld seam (e) of corrosion resistant alloy.
The beneficial effects of the invention are as follows：The present invention prevents steel pipe by built-up welding stainless steel short tube in prefabricated two sections of pipe ends
Scaling loss of the anticorrosive coat during pipeline welding in end；Dead mouth is welded using stainless steel wlding, it is ensured that the corrosion resistant of dead intraoral weld seam
Corrosion energy, reaches that pipe welding port exempts from the purpose of interior corrosion-resistanting interpolating port, realizes continuous, the raising pipeline military service of anticorrosive coat in steel pipe
Life-span；The present invention is by being machined overlay cladding, it is ensured that pipe string precision；
The present invention is that can be achieved to exempt the dead intraoral corrosion-resistanting interpolating port of steel pipe by two sections of pre- repaired mouth built-up welding short tubes, is solved
Corrosion-resistanting interpolating port technical bottleneck in the dead mouth weld bond of pipeline, simplifies the dead mouth of internal coat pipeline and connects head process, reduce interior anti-corrosion
The dead mouth of steel pipe connects head construction cost, extends the life cycle of pipeline, reduces safety collar caused by corrosive pipeline leakage
Protect risk.
Brief description of the drawings
Accompanying drawing 1 is the structural representation of first company's head short tube；
Accompanying drawing 2 is the structural representation of pipeline；
Accompanying drawing 3 is that the first company head short tube a and second connects the welding schematic diagram of head short tube b non-heap welding end respectively with pipeline；
Accompanying drawing 4 is the overall structure diagram after present invention welding；
In upper figure：The pre- repaired mouth layer a3 of base tube a1, interior anticorrosive coat a2, corrosion resistant alloy, groove a4, first connect head short tube a, second
Connect head short tube b, even pipeline c, head weld seam d, the dead mouth weld seam e of corrosion resistant alloy.
Embodiment
The preferred embodiments of the present invention are illustrated below in conjunction with accompanying drawing, it will be appreciated that preferred reality described herein
Apply example to be merely to illustrate and explain the present invention, be not intended to limit the present invention.
A kind of steel pipe two-part that the present invention is mentioned exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method, comprises the following steps：
(1) head short tube procedure of processing is connected：
(1) two sections of steel pipe short tubes are intercepted as first by the steel pipe specification of design code and connects head short tube a, second company's head short tube
B, stub length is more than 1.5D；
(2) the pipe end inwall circumference heap that head short tube a and second connects head short tube b is connected first using built-up welder in TIG steel pipes
Stainless steel material is welded, built-up welding layer depth is not less than 80mm；Overlay cladding thickness is not less than 1.5mm；(wherein, resurfacing welding material can be
One kind of austenite or ferritic stainless steel, two phase stainless steel and nickel-base alloy)
(3) the pre- repaired mouth layer a3 and short tube two ends groove a4 of lathe process corrosion resistant alloy, reference picture 1；
(2) the dead mouth of field pipes connects head step：
(1) the live dead mouths of process pipeline c one end therein, makes to reserve dead mouth length and the length phase of two sections of company's head short tubes
Together, referring to the drawings 2；
(2) the first company head short tube a and the second company head short tube b non-heap welding end are welded to connect with two ends pipeline c respectively, joined
According to accompanying drawing 3；
(3) butt welding mouth inwall is carried out after interior corrosion-resistanting interpolating port processing respectively, is welded using with pre- repaired mouth built-up welding identical wlding
Dead mouth weld seam, referring to the drawings 4；
(4) complete.
Referring to the drawings 1, wherein, the first company head short tube a that the present invention is mentioned includes base tube a1, interior anticorrosive coat a2, anti-corrosion conjunction
The pre- repaired mouth layer a3 of gold, groove a4, the base tube a1 inner chamber are provided with the pre- repaired mouth layer a3 of corrosion resistant alloy, in the pre- repaired mouth layer of corrosion resistant alloy
Interior anticorrosive coat a2 is provided between a3 and base tube a1, groove a4 is provided with base tube a1 end, can so inwall is closely realized
Anti-corrosion is connected, and easily facilitates operation, can also realize more preferable corrosion-resistanting interpolating port operation.
Above-mentioned first connects the company of being welded as head weld seam d between head short tube a and pipeline c.
Above-mentioned first company head short tube a and second is the dead mouth weld seam e of corrosion resistant alloy between connecting head short tube b.
The present invention operation principle be：
1st, by built-up welding stainless steel short tube in prefabricated two sections of pipe ends, prevent that anticorrosive coat is in pipeline welding process in pipe end
In scaling loss；
2nd, weld dead mouth using stainless steel wlding, it is ensured that the decay resistance of dead intraoral weld seam, reach that pipe welding port is exempted from interior
The purpose of corrosion-resistanting interpolating port, realizes the continuous of anticorrosive coat in steel pipe；
3rd, by being machined overlay cladding, it is ensured that pipe string precision.
Advantage of the invention is that：
The present invention connects head short tube by two sections of pre- repaired mouths of stainless steel of prefabrication, need to only be processed or provided pipe during site operation
Two sections of company's head short tubes are welded on anti-corrosion in two sections by the dead mouth length in road and even head assembly equal length (allowance weld gap) respectively
On pipeline, in weld bond after corrosion-resistanting interpolating port processing, 1 road stainless steel weld joint is only needed, you can ensure by prefabricated stainless steel weld overlays
Pipeline internal corrosion layer it is continuous, realize that pipe welding port exempts from the purpose of internal joint patch.
It is that can be achieved to exempt the dead intraoral corrosion-resistanting interpolating port of steel pipe by two sections of pre- repaired mouth built-up welding short tubes, solves pipeline dead
Corrosion-resistanting interpolating port technical bottleneck in mouth weld bond, simplifies the dead mouth of internal coat pipeline and connects head process, reduce interior antisepsis steel pipe
The dead mouth in road connects head construction cost, improves pipeline service life.
It is described above, only it is the part preferred embodiment of the present invention, any those skilled in the art may profit
Equivalent technical scheme is changed or is revised as with the technical scheme of above-mentioned elaboration.Therefore, the technology according to the present invention
Any simple modification or substitute equivalents that scheme is carried out, belong to the greatest extent the scope of protection of present invention.
Claims (4)
1. a kind of steel pipe two-part, which exempts from the dead mouth of interior corrosion-resistanting interpolating port, connects head method, it is characterized in that comprising the following steps：
(1) head short tube procedure of processing is connected：
(1) two sections of steel pipe short tubes are intercepted as first by the steel pipe specification of design code and connects head short tube (a), second company's head short tube
(b), stub length is more than 1.5D；
(2) head short tube (a) and second is connected first using built-up welder in TIG steel pipes and connects the pipe end inwall circumference heap of head short tube (b)
Stainless steel material is welded, built-up welding layer depth is not less than 80mm；Overlay cladding thickness is not less than 1.5mm；
(3) the pre- repaired mouth layer (a3) of lathe process corrosion resistant alloy and short tube two ends groove (a4)；
(2) the dead mouth of field pipes connects head step：
(1) dead mouth one end therein of live process pipeline (c), makes reserved dead mouth length identical with the length of two sections of company's head short tubes；
(2) the non-heap welding end of first company's head short tube (a) and second company's head short tube (b) is welded to connect with two ends pipeline (c) respectively；
(3) butt welding mouth inwall is carried out after interior corrosion-resistanting interpolating port processing respectively, and dead mouth is welded using with pre- repaired mouth built-up welding identical wlding
Weld seam；
(4) complete.
2. steel pipe two-part according to claim 1, which exempts from the dead mouth of interior corrosion-resistanting interpolating port, connects head method, it is characterized in that：It is described
First, which connects head short tube (a), includes the pre- repaired mouth layer (a3) of base tube (a1), interior anticorrosive coat (a2), corrosion resistant alloy, groove (a4), the base
The inner chamber of (a1) is managed provided with the pre- repaired mouth layer (a3) of corrosion resistant alloy, is provided between the pre- repaired mouth layer (a3) of corrosion resistant alloy and base tube (a1)
Interior anticorrosive coat (a2), groove (a4) is provided with the end of base tube (a1).
3. steel pipe two-part according to claim 1, which exempts from the dead mouth of interior corrosion-resistanting interpolating port, connects head method, it is characterized in that：It is described
First connects the company's of being welded as head weld seam (d) between head short tube (a) and pipeline (c).
4. steel pipe two-part according to claim 1, which exempts from the dead mouth of interior corrosion-resistanting interpolating port, connects head method, it is characterized in that：It is described
First connects between head short tube (a) and second company's head short tube (b) for the dead mouth weld seam (e) of corrosion resistant alloy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710583684.6A CN107191743A (en) | 2017-07-18 | 2017-07-18 | A kind of steel pipe two-part exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710583684.6A CN107191743A (en) | 2017-07-18 | 2017-07-18 | A kind of steel pipe two-part exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method |
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| Publication Number | Publication Date |
|---|---|
| CN107191743A true CN107191743A (en) | 2017-09-22 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710583684.6A Pending CN107191743A (en) | 2017-07-18 | 2017-07-18 | A kind of steel pipe two-part exempts from the dead mouth of interior corrosion-resistanting interpolating port and connects head method |
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| CN (1) | CN107191743A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112283463A (en) * | 2020-10-20 | 2021-01-29 | 海洋石油工程（青岛）有限公司 | Method for connecting plastic pipeline in ocean platform final assembly stage |
| CN109372442B (en) * | 2018-11-26 | 2024-06-11 | 中国石油大学(北京) | Joint coating process method of anti-corrosion oil pipe, anti-corrosion oil pipe and unit thereof |
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|---|---|---|---|---|
| RU2162188C1 (en) * | 2000-04-25 | 2001-01-20 | Общество с ограниченной ответственностью Научно-производственное предприятие "Антикормаш" | Method of rust protection of welded butt joints of pipelines with internal coating |
| CN203230975U (en) * | 2013-04-10 | 2013-10-09 | 河北四伟化学工业有限公司 | Pipeline connection device |
| CN105276336A (en) * | 2014-12-08 | 2016-01-27 | 中国石油天然气股份有限公司 | Welding pipeline internal corrosion prevention method and pipeline used for method |
| CN105983755A (en) * | 2015-01-28 | 2016-10-05 | 胜利油田金岛工程安装有限责任公司 | Surfacing welding method for enclosed connection of long-distance pipeline without mending |
-
2017
- 2017-07-18 CN CN201710583684.6A patent/CN107191743A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2162188C1 (en) * | 2000-04-25 | 2001-01-20 | Общество с ограниченной ответственностью Научно-производственное предприятие "Антикормаш" | Method of rust protection of welded butt joints of pipelines with internal coating |
| CN203230975U (en) * | 2013-04-10 | 2013-10-09 | 河北四伟化学工业有限公司 | Pipeline connection device |
| CN105276336A (en) * | 2014-12-08 | 2016-01-27 | 中国石油天然气股份有限公司 | Welding pipeline internal corrosion prevention method and pipeline used for method |
| CN105983755A (en) * | 2015-01-28 | 2016-10-05 | 胜利油田金岛工程安装有限责任公司 | Surfacing welding method for enclosed connection of long-distance pipeline without mending |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109372442B (en) * | 2018-11-26 | 2024-06-11 | 中国石油大学(北京) | Joint coating process method of anti-corrosion oil pipe, anti-corrosion oil pipe and unit thereof |
| CN112283463A (en) * | 2020-10-20 | 2021-01-29 | 海洋石油工程（青岛）有限公司 | Method for connecting plastic pipeline in ocean platform final assembly stage |
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Application publication date: 20170922 |
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