CN101220893A - Inservice underground pipe line on-line internal coating protection construction equipment - Google Patents
Inservice underground pipe line on-line internal coating protection construction equipment Download PDFInfo
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- CN101220893A CN101220893A CNA2008100084251A CN200810008425A CN101220893A CN 101220893 A CN101220893 A CN 101220893A CN A2008100084251 A CNA2008100084251 A CN A2008100084251A CN 200810008425 A CN200810008425 A CN 200810008425A CN 101220893 A CN101220893 A CN 101220893A
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Abstract
The invention relates to an in-service underground pipeline online internal coating protection construction process and a special equipment thereof. The construction process comprises the pre-processing of the pipeline, the construction of a plugging layer and the coating of the underlayer and the surface layer of an internal anticorrosion coating; the construction of the plugging layer comprises that a rendering of the plugging layer is applied in the pipeline, so as to plug up leaks and cracks; an enclosing disposal is carried out on the micropores and micro-cracks on the surface of the plugging layer; a diluted plugging layer micropore enclosing coating is applied on the surface of the dried plugging layer; the coating of the underlayer and the surface layer of the internal anticorrosion coating comprises that an internal anticorrosion coating underlayer is coated after the surface of the liner enclosing coating is dried, and an internal anticorrosion coating surface layer is finally coated after the surface of the underlayer coating of the internal coating is dried. The special equipment comprises a pipeline cleaning equipment, an online internal coating equipment and an internal coating quality detecting equipment. The invention is suitable for the plugging repair of used low pressure pipelines, the online construction of internal coatings, the plugging repair of urban coal gas pipelines; the plugging repair of urban water supply pipeline and the plugging repair of oilfield sewage pipelines.
Description
The application is dividing an application of Chinese invention patent application, the applying date of original application: on April 30th, 2005, application number: 200510046362.5, invention and created name: at online inner coating protection construction process of service underground pipeline and special device thereof, publication number: CN1858477A; In the patent examination process,, propose this and divide an application because hot-extrusion method and specialized mould in the original application do not belong to a total inventive concept.
Technical field
The present invention relates to recovery technique, be specially a kind of at the online inner coating protection construction equipment of service underground pipeline at service underground pipeline.
Background technique
Split in burn into fouling and early stage corrosion that oil, gas, the waterpipe ubiquity of labour are serious, have a strong impact on ordinary production, even reasonably do not scrap in early days.
Following typical case can clearly be seen that this point.The early stage corrosion failure of hot water piping shown in Fig. 1-2, be 30 years the projected life of this hot water piping, only be 4 years actual life, perforation thickness: 22 corrosion failure/rice.As shown in Figure 3, pipeline scaling situation (when hanging down flow velocity); As shown in Figure 4, pipeline and valve scaling are scrapped situation in early days.
Result of study shows (Fig. 5), in the bittern of the high chloride ion content of oil well output, along with hydrogen sulfide content rises to 261ppm gradually from 50ppm, strengthened the brittle failure receptance of low alloy steel (UNS G11180), thereby the tendency and the danger of early fracture have obviously taken place.
(1) maintenance needs
The pipeline of early stage corrosion failure and fouling, need in good time pigging, leak stopping, in be coated with barrier coating, reach the purpose of lengthening the life and using, avoid scrapping in advance.
(2) Reliability Engineering under the low investment condition
The piping design stage, when often ignoring pipeline and in corrosive atmosphere, using since local etching cause boring a hole in early days or splitting.In good time maintenance is to remedy this not enough important technique measure.Also be a little investment, improve the operation technique of lengthening the life of pipeline reliability.
Pipeline recovery technique present situation is as follows:
The pipeline recovery technique mainly contains following three kinds of methods: 1) air-flow cladding process; 2) slide block cladding process; 3) flexible pipe lining method.
Wherein, air-flow cladding process and flexible pipe lining method need be implemented coating and flexible pipe lining, technology and tooling device complexity, operating expenses height under the intensification condition; And, can not do online construction to long distance line at normal temperatures.Flexible pipe lining method still can not prevent existing local etching perforation and corrode further developing of the position of splitting.And slide block apply rule can adopt conventional pigging technology and in be coated with the technology online construction of long distance line at normal temperatures.This process engineering can be used for applying corrosion-inhibiting coating in straight tube and bend pipe.
In fact, the external coating of Structural Hardware is the most widely used anticorrosive measure.According to external statistics, in the expense of corrosion protection, the expense that is used for surface protection accounts for more than 90% of overall cost.Japan's statistics in 1993 of announcing from table 1 as can be seen, the expenditure of corrosion protection is mainly used in surface protection.
Usually, under the situation that can't change structural material, the maintenance of existing structure, the topmost often anti-corrosion measure of external coating also is the most simple and easy to do anticorrosive measure.
Table 1 Japan is to the statistics (1993) of various anticorrosive measure expenses
| The corrosion protection countermeasure | The corrosion protection expense, hundred million yen | Ratio, % |
| External coating | 15954.8 | 62.55 |
| Treatment of Metal Surface | 6476.2 | 25.39 |
| Corrosion resistant material | 2388.2 | 9.36 |
| Rust preventive oil | 156.5 | 0.61 |
| Corrosion inhibitor | 161.0 | 0.63 |
| Electrical corrosion protection | 157.5 | 0.62 |
| Corrosion research | 215.1 | 0.84 |
| Amount to | 25509.3 | 100.00 |
A large amount of maintenances at the underground old pipeline of labour need a whole set of high-caliber surface protection process technology, the purpose that reaches safety guarantee and lengthen the life and use.
Summary of the invention
The object of the present invention is to provide a kind ofly, use the leak stopping reparation and the operation technique of lengthening the life of the old pipeline in ground at business enterprise expands such as communal facilitys such as town gas, water, oil field and chemical industry at online inner coating protection construction process of service underground pipeline and special device thereof.
Technological scheme of the present invention is:
A kind of in the online inner coating protection construction process of service underground pipeline, comprise the pretreatment of pipeline, the construction of leak stopping layer and the coating of inner anticorrosioning coating bottom and surface layer, concrete steps are as follows:
The pretreatment of pipeline:
(1) carries out the internal surface pigging with cotton bullet and the sliding brush of steel wire, remove inner-walls of duct corrosion products and rust deposite, finally expose the metal true qualities, then hair is scraped on the inner-walls of duct surface with cotton bullet;
(2) carry out internal surface oil removing and high pressure water cleaning with aqueous cleaning agent and wiper;
The construction of leak stopping layer:
(1) in pipeline, applies the bottoming of leak stopping layer, stop up a loophole and crackle;
(2) sealing of leak stopping laminar surface micropore and microcrack is handled; At dried leak stopping laminar surface, be coated with the leak stopping layer micropore seal coat of one dilution, film thickness is 60～80 μ m;
The coating of inner anticorrosioning coating bottom and surface layer:
(1) behind lining seal coat surface drying, be coated with the inner anticorrosioning coating bottom one, film thickness is 100～120 μ m;
(2) behind undercoating primer coating surface drying, be coated with the inner anticorrosioning coating surface layer at last one, film thickness is 120～150 μ m.
Add interface treating agent in lining, lining mixes in proportion with interface treating agent at 3: 1, and after water was mixed well, brushing was in the inner-walls of duct bottoming, and thickness is 250～350 μ m.
Require as follows in the lining construction process:
(1) construction environment
On-the-spot construction temperature must not be lower than 4 ℃;
(2) pigging
With aqueous cleaning agent and wiper with twice of inner surface of pipeline oil removing;
(3) inner surface of pipeline is wetting
Should wash wetting after the inner surface of pipeline cleaning;
(4) lining construction
Utilize the pressure spreader to construct;
(5) lining maintenance
Adopt the natural curing method, curing temperature must not be lower than 10 ℃, and curing time must not be less than 24h.
In dried liner surface, be coated with the double-component lining seal coat that mixes together earlier, treat that paint film was coated with down the road lacquer in 4 hours behind the surface drying; Behind the lining seal coat surface drying, brushing undercoating bottom treats that paint film can be coated with down the road lacquer in 4 hours behind the surface drying; After coating had been constructed, pipeline was placed and was re-used in 7 days.
At the online inner coating protection construction of service underground pipeline special device, comprise pigging equipment, online inner coating equipment, undercoating quality detection apparatus; Wherein, pigging equipment comprises: engineering truck, manograph, pig signal transmitter, wiper, dress generator and air compressor in the engineering truck, pending pipeline is connected with manograph, places the wiper in the pending pipeline to be provided with the pig signal transmitter; Online inner coating equipment comprises: applicator, be coated with in underground pipeline, with underground in be coated with wiper or applicator transmitter installation, wiper or the applicator recovering device that pipeline is communicated with, applicator is provided with the applicator position indicator, feed pipe, pressure gauge, exhaust duct are equipped with in the wiper or the applicator transmitter installation outside, on this feed pipe feeding valve is housed, on this exhaust duct outlet valve is housed, on wiper or the applicator recovering device pressure gauge, exhaust duct are housed, on this exhaust duct outlet valve are housed; The undercoating quality detection apparatus comprises: peep in the pipeline detector, with pipeline in peep the ground imaging management apparatus that detector links to each other.
The invention has the beneficial effects as follows:
1, the present invention's technological test under the condition of chamber and performance test of being undertaken by NBS by experiment, the cast iron town gas pipeline section leak stopping that original joint can be leaked is repaired.Withstand voltage properties can be stabilized in 8 kilograms per centimeter for a long time
2(the town gas pipeline is only required withstand voltage 3 kilograms per centimeter
2, therefore, withstand voltage to 8 kilograms per centimeter
2The time, do not require the pressure test under the high pressure condition more of carrying out), more high pressure and temperature conditions down oil, gas, the performance of water pipeline in typical corrosive environment in further testing.According to report, the undercoating that class is more much lower than the technology of the present invention, can also reach more than 60 years the working life in seawater.Therefore,, can expect according to conservative estimation, adopt undercoating corrosion protection recovery technique of the present invention after, can obtain corresponding prolongation working life at least.
2, the present invention is suitable for applying in following pipeline: 1) the leak stopping reparation of the old pipeline of low pressure and the online construction of undercoating; 2) the leak stopping reparation of town gas pipeline; 3) the leak stopping reparation of city supply water pipeline; 4) the leak stopping reparation of oilfield sewage pipeline.
3, market prospects are extensive.Following a large amount of in early stage damages such as the old pipeline ubiquity of labour corrosion failure/crackle in various degree, the process engineering that extensively needs the on-line maintenance maintenance and lengthen the life and use: 1) oil in as fine as a spider's web oil field, gas, water piping system; 2) a large amount of town gas and water system; 3) chemical engineering piping systems etc.
Description of drawings
Fig. 1-Fig. 2 is the early stage corrosion failure picture of hot water piping, and be 30 years projected life, and only be 4 years actual life, perforation thickness: 22 corrosion failure/rice.
Fig. 3 is pipeline scaling (when hanging down a flow velocity) picture.
Fig. 4 scraps picture in early days for pipeline and valve scaling.
Fig. 5 is UNS G11180 steel stress～strain curve in 5%NaCl solution.
Fig. 6 is the schematic representation of pigging operation.
Fig. 7 is online inner coating equipment schematic representation.
Whether Fig. 8 is a undercoating quality detection apparatus schematic representation, utilize clever pipeline pig (Smart pipeline pig) to have pin hole to detect to coating.
Among the figure, 1 engineering truck; 2 manographs; 3 pig signal transmitters; The 4PIG wiper; 5 feeding valves; 6 pressure gauges; 7 outlet valves; 8 applicator position indicators; 9 pressure gauges; 10 outlet valves; 11 wipers or applicator recovering device; 12 are coated with pipeline in underground; 13 applicators; 14 wipers or applicator transmitter installation; 15 ground imaging management apparatus; Peep detector in 16 pipelines.
Embodiment
Plugging underground pipeline reparation of the present invention and in be coated with anticorrosion main construction equipment and frock, be scene or field work Armoured Engineer Vehicle, comprising: pigging equipment, online inner coating equipment, undercoating quality detection apparatus etc.
As shown in Figure 6, the schematic representation of pipeline pig (Pig) pigging operation.Pigging equipment comprises: engineering truck 1, manograph 2, pig signal transmitter 3, PIG wiper 4, dress generator and air compressor in the engineering truck 1, pending pipeline is connected with manograph 2, places the PIG wiper 4 in the pending pipeline to be provided with pig signal transmitter 3.
Its working procedure is as follows:
(1) utilizes compressed air, promote the pipeline pig wiper of band cutter, dirt in the pipeline and rust are removed, must repeat in case of necessity,, expose the true qualities (be equivalent to the surface and reach 2.5 grades of Sa) of steel surface up to dirt in the pipeline and rust Ex-all.
(2) utilize compressed air, promote the pipeline pig wiper of band wire brush, inner-walls of duct is scraped hair, then, remove the greasy dirt of metal surface, be beneficial to strengthen the adhesion of coating at steel pipe internal-surface with aqueous cleaning agent.
(3) utilize manograph monitor tube internal pressure to change, the signal that utilizes track and localization instrument reception pig signal transmitter to send positions.
As shown in Figure 7, online inner coating equipment schematic representation.Online inner coating equipment comprises: applicator 13, be coated with in underground pipeline 12, with underground in be coated with wiper or applicator transmitter installation 14, wiper or the applicator recovering device 11 that pipeline 12 two ends are communicated with respectively, applicator 13 is provided with applicator position indicator 8, feed pipe, pressure gauge 6, exhaust duct are equipped with in the wiper or applicator transmitter installation 14 outsides, feeding valve 5 is housed on the feed pipe, outlet valve 7 is housed on the exhaust duct, on wiper or the applicator recovering device 11 pressure gauge 9, exhaust duct are housed, outlet valve 10 is housed on the exhaust duct.
By feeding valve coating is added between two applicators, utilizes air compressor to promote applicator after filling it up with and move ahead, reach the purpose of coating, utilize the coating position indicator to position tracking, after coating is finished, in recovering device, reclaim applicator.
As shown in Figure 8, undercoating quality detection apparatus schematic representation.The undercoating quality detection apparatus comprises: peep in the pipeline detector 16, with pipeline in peep the ground imaging management apparatus 15 that detector 16 links to each other.
Utilize clever pipeline pig (Smart pipeline pig) whether to have pin hole to detect to coating.When condition did not possess, stop leakage in the roof instrument and thickness meter of the coating pin hole of available routine detected the coating at the two ends of band coating pipeline.
Apply new process in the pipe plugging reparation of the present invention and the use of lengthening the life, comprise the pretreatment of pipeline, the construction process of leak stopping layer, the construction process of anticorrosive coating, concrete steps are as follows:
1, the pretreatment of pipeline:
(1) carries out the internal surface pigging with cotton bullet (foamed polyurethane bullet) and the sliding brush of steel wire, remove inner-walls of duct corrosion products and rust deposite, finally expose the metal true qualities, then hair is scraped on the inner-walls of duct surface with cotton bullet;
(2) carry out internal surface oil removing (twice) and high pressure water cleaning with aqueous cleaning agent and wiper.
2, the construction of leak stopping layer
(1) in pipeline, applies the bottoming of leak stopping layer, stop up a loophole and crackle;
(2) sealing of leak stopping laminar surface micropore and microcrack is handled; At dried leak stopping laminar surface, be coated with the leak stopping layer micropore seal coat of one dilution, film thickness is 60～80 μ m.
For making lining and inner-walls of duct keep good cementability, in lining, add interface treating agent.Lining mixes in proportion with interface treating agent at 3: 1, and after water was mixed well, brushing was in the inner-walls of duct bottoming, and thickness is approximately 300 μ m.
Lining construction requires:
(1) construction environment
On-the-spot construction temperature must not be lower than 4 ℃.
The site operation pipeline section should clean by related standards regulation before lining construction, organize, welding, pressure test, leak test, and externally anticorrosive coating repaired mouth is mended and hindered, and except that site operation pipeline section two ends, the backfill of the pipe trench of remaining part.
(2) pigging
With aqueous cleaning agent and wiper with twice of inner surface of pipeline oil removing.Should first pigging before the lining construction, remove foreign material such as stone in the site operation pipeline section, mud.
(3) inner surface of pipeline is wetting
Should wash wetting after the inner surface of pipeline cleaning.The internal surface that washes after wetting must not have dust, also ponding must not be arranged.
(4) lining construction
Utilize the pressure spreader to construct.
(5) lining maintenance
Adopt the natural curing method, curing temperature must not be lower than 10 ℃, and curing time must not be less than 24h.
(6) quality inspection
Test at its outward appearance of lining maintenance expiration back reply, crackle and thickness.
3, the coating of inner anticorrosioning coating bottom and surface layer
(1) behind lining seal coat surface drying, be coated with the inner anticorrosioning coating bottom one, film thickness is 100～120 μ m.
(2) behind undercoating primer coating surface drying, be coated with the inner anticorrosioning coating surface layer at last one, film thickness is 120～150 μ m.After coating had been constructed, if the duration allows, pipeline need be placed and re-use in 7 days.
The construction requirement of anticorrosive coating:
1, coating must guarantee the bone dry of lining before brushing.
2, in dried liner surface, be coated with the double-component lining seal coat that mixes together earlier, paint film requires evenly, must not holiday.Treat that paint film can be coated with down the road lacquer in 4 hours behind the surface drying.
3, behind the lining seal coat surface drying, brushing undercoating bottom.Paint film requires evenly, must not holiday.Treat that paint film can be coated with down the road lacquer in 4 hours behind the surface drying.
4, behind the undercoating bottom surface drying, brushing undercoating surface layer.Paint film requires evenly, must not holiday.To under the prerequisite of not trickling, be coated with thick when being coated with the undercoating surface layer as far as possible.
5, coating quality inspection
(1) visual examination: coating is full, and the surface presents the paint film of light, will remove coating to the fold and the bulge on surface.
(2) bonding force inspection: after coating was solidified fully, the tongue type that cuts with a knife out otch firmly tore coating, can only rupture, and can not large size tear.Underproof pipeline section should tear construction again.
(3) pin hole inspection: coating is done solid work the back and is hunted leak with 2000 volts of electrical spark, and the discovery pin hole is answered coating.
(4) thickness inspection: coating is measured thickness with coating thickness detector after solidifying fully.
Claims (1)
1. one kind at the online inner coating protection construction equipment of service underground pipeline, it is characterized in that comprising pigging equipment, online inner coating equipment, undercoating quality detection apparatus; Wherein, pigging equipment comprises: engineering truck (1), manograph (2), pig signal transmitter (3), wiper (4), dress generator and air compressor in the engineering truck (1), pending pipeline is connected with manograph (2), places the wiper (4) in the pending pipeline to be provided with pig signal transmitter (3); Online inner coating equipment comprises: applicator (13), be coated with pipeline (12) in underground, with underground in be coated with wiper or the applicator transmitter installation (14) that pipeline (12) is communicated with, wiper or applicator recovering device (11), applicator (13) is provided with applicator position indicator (8), feed pipe is equipped with in the wiper or applicator transmitter installation (14) outside, pressure gauge (6), exhaust duct, feeding valve (5) is housed on this feed pipe, outlet valve (7) is housed on this exhaust duct, on wiper or the applicator recovering device (11) pressure gauge (9) is housed, exhaust duct is equipped with outlet valve (10) on this exhaust duct; The undercoating quality detection apparatus comprises: peep in the pipeline detector (16), with pipeline in peep the ground imaging management apparatus (15) that detector (16) links to each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008100084251A CN101220893A (en) | 2005-04-30 | 2005-04-30 | Inservice underground pipe line on-line internal coating protection construction equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008100084251A CN101220893A (en) | 2005-04-30 | 2005-04-30 | Inservice underground pipe line on-line internal coating protection construction equipment |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005100463625A Division CN100447476C (en) | 2005-04-30 | 2005-04-30 | Construction process for online inner coating protection of on-service underground pipeline and its special apparatus |
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| CN101220893A true CN101220893A (en) | 2008-07-16 |
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| CNA2008100084251A Pending CN101220893A (en) | 2005-04-30 | 2005-04-30 | Inservice underground pipe line on-line internal coating protection construction equipment |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104923536A (en) * | 2015-05-22 | 2015-09-23 | 沈阳永业实业有限公司 | Communication positioning device and method applied to pipe cleaner inside benthal oil pipeline |
| CN110067945A (en) * | 2019-04-28 | 2019-07-30 | 姚育晶 | Repair apparatus is goed deep into a kind of leak detection for closestool inner tube in sanitary ware |
| CN110131587A (en) * | 2019-04-17 | 2019-08-16 | 汉正检测技术有限公司 | A kind of pipe detection device |
| CN111207299A (en) * | 2020-01-08 | 2020-05-29 | 中国石油大学(北京) | Surface modification method for oil field gathering and transportation pipeline |
-
2005
- 2005-04-30 CN CNA2008100084251A patent/CN101220893A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104923536A (en) * | 2015-05-22 | 2015-09-23 | 沈阳永业实业有限公司 | Communication positioning device and method applied to pipe cleaner inside benthal oil pipeline |
| CN110131587A (en) * | 2019-04-17 | 2019-08-16 | 汉正检测技术有限公司 | A kind of pipe detection device |
| CN110067945A (en) * | 2019-04-28 | 2019-07-30 | 姚育晶 | Repair apparatus is goed deep into a kind of leak detection for closestool inner tube in sanitary ware |
| CN111207299A (en) * | 2020-01-08 | 2020-05-29 | 中国石油大学(北京) | Surface modification method for oil field gathering and transportation pipeline |
| CN111207299B (en) * | 2020-01-08 | 2021-08-06 | 中国石油大学(北京) | Surface modification method for oil field gathering and transportation pipeline |
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Open date: 20080716 |