阅读说明：本技术 一种环氧钢套筒修复管道环焊缝缺陷的装置及工艺 (Device and process for repairing pipeline girth weld defects by using epoxy steel sleeve ) 是由 马卫锋 任俊杰 王珂 曹俊 聂海亮 蔡克 宋恩鹏 罗金恒 赵新伟 于 2019-09-26 设计创作，主要内容包括：本发明公开一种环氧钢套筒修复管道环焊缝缺陷的装置及工艺,包括复合环氧钢质套筒、真空泵和注胶装置,钢质套筒设置在待修复管道的外侧,纤维布缠绕在待修复管道的外壁,纤维布与钢质套筒内壁之间有间隙；密封体设置在钢质套筒两端内壁与管道之间,填充胶体设置在钢质套筒、待修复管道以及密封体之间的间隙中；钢质套筒上沿径向开设定位螺纹孔,钢质套筒顶部顺着胶体流向开设抽真空口/溢胶口和排气/观察孔；并公开了修复工艺,能有效解决传统环氧钢质套筒填充树脂脆化开裂、固化气泡和空腔问题,确保复合环氧钢质套筒与钢质管体之间具有良好的匹配性,分担管道环焊缝承受的环向载荷和轴向载荷,约束环焊缝缺陷轴向开裂。(The invention discloses a device and a process for repairing a pipeline girth weld defect by an epoxy steel sleeve, which comprises a composite epoxy steel sleeve, a vacuum pump and a glue injection device, wherein the steel sleeve is arranged at the outer side of a pipeline to be repaired, a fiber cloth is wound on the outer wall of the pipeline to be repaired, and a gap is reserved between the fiber cloth and the inner wall of the steel sleeve; the sealing bodies are arranged between the inner walls of the two ends of the steel sleeve and the pipeline, and the filling colloid is arranged in gaps among the steel sleeve, the pipeline to be repaired and the sealing bodies; the steel sleeve is provided with a positioning threaded hole along the radial direction, and the top of the steel sleeve is provided with a vacuumizing hole/glue overflow hole and an exhaust/observation hole along the direction of the glue flow; the repair process is also disclosed, the problems of brittle cracking, solidified bubbles and cavities of the traditional epoxy steel sleeve filled with resin can be effectively solved, good matching performance between the composite epoxy steel sleeve and the steel pipe body is ensured, the circumferential load and the axial load borne by the pipeline circumferential weld are shared, and the circumferential weld defect axial cracking is restrained.)

1. The device for repairing the pipeline girth weld defects by using the epoxy steel sleeve is characterized by comprising a composite epoxy steel sleeve, a vacuum pump and a glue injection device, wherein the composite epoxy steel sleeve comprises fiber cloth (2), a steel sleeve (3), a connecting bolt (4), a positioning bolt (5), a sealing body and a filling colloid; the steel sleeve (3) is arranged on the outer side of the pipeline (1) to be repaired, the fiber cloth (2) is wound on the outer wall of the pipeline (1) to be repaired, and a gap is reserved between the fiber cloth (2) and the inner wall of the steel sleeve (3); the sealing bodies are arranged between the inner walls of the two ends of the steel sleeve (3) and the pipeline (1), and the filling colloid is arranged in gaps among the steel sleeve (3), the pipeline (1) to be repaired and the sealing bodies; positioning threaded holes are radially formed in the steel sleeve (3), and a vacuumizing hole/glue overflow hole (9) and an exhaust/observation hole (10) are formed in the top of the steel sleeve (3) along the direction of the glue flow; the bottom of the steel sleeve (3) is provided with a glue injection port (8);

a positioning bolt (5) is arranged in the positioning threaded hole, the steel sleeve (3) comprises two semi-cylindrical sleeves, flanges are arranged at the edges of the two semi-cylindrical sleeves along the axial direction, and a connecting bolt (4) penetrates through the flanges to be connected to form the steel sleeve (3);

the air inlet of the vacuum pump is communicated with the vacuumizing hole/glue overflow hole (9), and the outlet of the glue injection device is communicated with the glue injection hole (8).

2. The device for repairing the circumferential weld defect of the pipeline by the epoxy steel sleeve as claimed in claim 1, wherein the vacuumizing/glue overflowing opening (9), the glue injecting opening (8) and the exhaust/observation hole (10) are all threaded holes, the vacuumizing/glue overflowing opening (9) is connected with a vacuumizing joint, the glue injecting opening (8) is connected with a glue injecting joint, and the vacuumizing joint and the glue injecting joint are both standard joints; a vacuum pumping control valve (12) is arranged on a pipeline for communicating the vacuum pump with the vacuum pumping port/the glue overflow port (9).

3. The device for repairing the circumferential weld defect of the pipeline by the epoxy steel sleeve as claimed in claim 2, wherein the glue injection device comprises a glue injection funnel, a glue outlet is formed in the bottom of the glue injection funnel and is communicated with the glue injection port (8) through a steel wire hose, and a glue injection control valve (11) is arranged on the pipeline between the glue outlet and the glue injection port (8).

4. The apparatus for repairing a pipe girth weld defect with the epoxy steel sleeve as claimed in claim 1, wherein a sealing screw is provided in the exhaust/inspection hole (10).

5. The apparatus for repairing the pipe girth weld defect with the epoxy steel sleeve as claimed in claim 1, wherein the heating belt and the thermometer are arranged outside the steel sleeve (3).

6. A process for repairing a pipe girth weld defect using an epoxy steel sleeve with the apparatus of claim 1, comprising the steps of:

carrying out surface treatment on the steel pipe (1) to be repaired;

winding fiber cloth (2) on the surface of the treated steel pipe (1) to be repaired, wherein the fiber cloth (2) adopts 0-degree/90-degree bidirectional glass fiber cloth;

sealing bodies are arranged at the positions of two ends of the steel sleeve (3);

assembling the steel sleeve (3), adjusting the positioning bolt (5) to enable the steel sleeve (3) to be in a set position, gradually screwing the connecting bolt (4), and sealing the connecting surface of the steel sleeve (3);

connecting a vacuumizing device and a glue injection device, and vacuumizing to a set vacuum degree;

injecting the filling adhesive for filling the adhesive into the adhesive injection device for injecting the adhesive until the filling adhesive overflows from the vacuumizing port/adhesive overflowing port 9, stopping injecting the adhesive, and stopping vacuumizing;

curing the filling adhesive injected into the steel sleeve (3);

and (4) detaching the glue injection joint and the glue overflow joint, plugging by using an end enclosure, cutting off the redundant parts of the positioning bolt (5) and the observation hole bolt, and finally performing anticorrosive treatment.

7. The process for repairing the girth weld defect of the pipeline by using the epoxy steel sleeve as claimed in claim 6, wherein the vacuumizing device comprises sealing bodies, a vacuumizing opening/glue overflowing opening (9) and a vacuumizing control valve (12) which are arranged at two ends of the steel sleeve (3), the pipeline for connecting the vacuum pump, the vacuumizing control valve (12) and the vacuumizing opening/glue overflowing opening (9) adopts a steel wire hose, the sealing bodies comprise end sealing rubber (6) and end sealing glue (7), the end sealing rubber (6) is arranged in the gap between the steel sleeve (3) and the steel pipe (1) to be repaired, and the end sealing glue (7) is coated on the outer sides of the steel sleeve (3) and the end sealing glue (6).

8. The process for repairing a pipe girth weld defect with an epoxy steel sleeve as claimed in claim 7, wherein the end sealant (7) is a sealant compound comprising a first component and a second component; the first component comprises 30-70 parts of E-51 epoxy resin, 50-100 parts of steel powder, 10-40 parts of silver powder and 10-25 parts of random carboxyl nitrile rubber by weight, and the second component comprises 10-30 parts of modified amine curing agent, 1-10 parts of fumed silica, 2-10 parts of 2,4, 6-tris (dimethylaminomethyl) -phenol and no more than 15 parts of silane coupling agent by weight; the proportion of the first component to the second component is (5-7): 1 by weight, and the first component and the second component are uniformly mixed to obtain the sealing adhesive.

9. The process for repairing the defect of the circumferential weld of the pipeline by using the epoxy steel sleeve as claimed in claim 6, wherein the glue injection device comprises a glue injection port (8), an exhaust/observation hole (10) and a glue injection control valve (11), and the glue injection funnel, the glue injection control valve (11) and the glue injection port (8) are also connected by using a steel wire hose.

10. The process for repairing a pipe girth weld defect with an epoxy steel sleeve as claimed in claim 6, wherein the filling adhesive comprises a component A and a component B; the component A comprises, by weight, 80-100 parts of 828 epoxy resin, 10-30 parts of 678 reactive diluent, 10-30 parts of Qishi N toughening agent and no more than 2 parts of 550 defoaming agent, and the component B comprises, by weight, 30-60 parts of DL51 modified fatty amine curing agent, 3-8 parts of fumed silica and 1-5 parts of silane coupling agent, and the two are uniformly mixed to obtain the filling adhesive; the proportion of the A component and the B component is (2-4) to 1 by weight.

Technical Field

The invention belongs to the technical field of pipeline defect repair, and particularly relates to a device and a process for repairing a pipeline girth weld defect by an epoxy steel sleeve.

Background

Oil and gas pipeline transportation is one of five major transportation industries, and the oil and gas pipeline in China breaks through 12 kilometers at present. The oil and gas pipeline often forms various pipe body defects due to manufacturing welding defects, internal and external corrosion, third-party damage and the like, so that accidents such as pipeline burst, leakage and the like are caused, the safe operation and conveying operation capacity of the pipeline are seriously influenced, and how to effectively repair and reinforce the detected pipe body defects is a key technical measure for ensuring the safe operation of the pipeline and improving the conveying benefit. The existing pipeline repairing technology comprises welding scar repairing, sleeving, clamping, pipe replacing, composite material repairing and the like. The epoxy steel sleeve repairing technology is a pipeline repairing technology invented by gas in the United kingdom in the last 70 years and used firstly, and is mainly used for repairing the weld defects of oil and gas pipelines. The technology is a product improved on the basis of an A-type sleeve, and is characterized in that a certain gap is usually formed between an external steel sleeve and a steel pipe surface, a high-strength filling material is filled in the gap on a construction site, the load or stress of a defect part is transferred to the steel sleeve by using epoxy resin, and the steel sleeve can bear higher hoop stress and axial stress, and has two structures: side seam welding and flange connection.

In recent years, with the prominent problems of pipeline girth weld defects, failure fracture and the like, the problem of repairing and maintaining the girth weld is a key engineering problem which is urgently needed to be solved by pipeline companies and industries. The method for repairing the defect of the circumferential weld mainly comprises the following steps: polishing, heavy anchor clamps, trade pipe, B type sleeve, epoxy steel sleeve etc. wherein, polish and only can restore the shallow defect of surface, heavy anchor clamps belong to interim restoration, trade the pipe and need stop defeatedly, and B type sleeve need step-down to fire, and above method all has very big limitation, and epoxy steel sleeve operation is simple and convenient, need not the welding, does not have the various risks of the operation of firing, and the advantage is obvious, has received pipeline manager's favor. However, the applied epoxy steel sleeve repair technology and products which are not authoritative in the current market at home also have more engineering practice problems, including brittle cracking of the filling resin material, serious cavity problems, curing bubbles, unsatisfactory sleeve design and the like.

Disclosure of Invention

The invention aims to provide a device and a process for repairing a pipeline girth weld defect by an epoxy steel sleeve, which effectively solve the problems of embrittlement cracking, curing bubbles and cavities of the traditional epoxy steel sleeve filled with resin under the condition of vacuum impregnation, thereby achieving the purpose of repairing the girth weld defect.

In order to achieve the purpose, the technical scheme adopted by the invention is that the device for repairing the defect of the circumferential weld of the pipeline by using the epoxy steel sleeve comprises a composite epoxy steel sleeve, a vacuum pump and a glue injection device, wherein the composite epoxy steel sleeve comprises fiber cloth, a steel sleeve, a connecting bolt, a positioning bolt, a sealing body and a filling colloid; the steel sleeve is arranged on the outer side of the pipeline to be repaired, the fiber cloth is wound on the outer wall of the pipeline to be repaired, and a gap is reserved between the fiber cloth and the inner wall of the steel sleeve; the sealing bodies are arranged between the inner walls of the two ends of the steel sleeve and the pipeline, and the filling colloid is arranged in gaps among the steel sleeve, the pipeline to be repaired and the sealing bodies; the steel sleeve is provided with a positioning threaded hole along the radial direction, and the top of the steel sleeve is provided with a vacuumizing hole/glue overflow hole and an exhaust/observation hole along the direction of the glue flow; the bottom of the steel sleeve is provided with a glue injection port;

the positioning threaded hole is internally provided with a positioning bolt, the steel sleeve comprises two semi-cylindrical sleeves, flanges are axially arranged at the edges of the two semi-cylindrical sleeves, and the connecting bolt penetrates through the flanges to be connected to form the steel sleeve;

the air inlet of the vacuum pump is communicated with the vacuumizing hole/glue overflow hole, and the outlet of the glue injection device is communicated with the glue injection hole.

The vacuumizing port/glue overflow port, the glue injection port and the exhaust/observation hole are all threaded holes, the vacuumizing port/glue overflow port is connected with a vacuumizing connector, the glue injection port is connected with a glue injection connector, and the vacuumizing connector and the glue injection connector are both standard connectors; a vacuum pumping control valve is arranged on a pipeline of the vacuum pump communicated with the vacuum pumping port/the glue overflowing port.

The glue injection device comprises a glue injection funnel, a glue outlet is formed in the bottom of the glue injection funnel and communicated with the glue injection port through a steel wire hose, and a glue injection control valve is arranged on a pipeline between the outlet and the glue injection port.

And a sealing screw is arranged in the exhaust/observation hole.

And a heating belt and a thermometer are arranged outside the steel sleeve.

A process for repairing the defect of the circumferential weld of a pipeline by using an epoxy steel sleeve comprises the following steps:

carrying out surface treatment on the steel pipe to be repaired;

winding fiber cloth on the surface of the treated steel pipe to be repaired, wherein the fiber cloth is 0 degree/90 degree bidirectional glass fiber cloth;

sealing bodies are arranged at the positions of two ends of the steel sleeve;

assembling the steel sleeve, adjusting the positioning bolt to enable the steel sleeve to be in a set position, gradually screwing the connecting bolt, and sealing the connecting surface of the steel sleeve;

connecting a vacuumizing device and a glue injection device, and vacuumizing to a set vacuum degree;

injecting the filling adhesive for filling the adhesive into the adhesive injection device for injecting the adhesive until the filling adhesive overflows from the vacuumizing port/adhesive overflowing port 9, stopping injecting the adhesive, and stopping vacuumizing;

curing the filling adhesive injected into the steel sleeve;

and (4) detaching the glue injection joint and the glue overflow joint, plugging by using an end enclosure, cutting off redundant parts of the positioning bolt and the observation hole bolt, and finally performing anticorrosive treatment.

The vacuumizing device comprises sealing bodies arranged at two ends of the steel sleeve, a vacuumizing opening/glue overflow opening and a vacuumizing control valve, wherein a pipeline connecting the vacuum pump, the vacuumizing control valve and the vacuumizing opening/glue overflow opening adopts a steel wire hose, the sealing bodies comprise end sealing rubber and end sealing glue, the end sealing rubber is arranged in a gap between the steel sleeve and the steel pipe to be repaired, and the end sealing glue is coated on the outer sides of the steel sleeve and the end sealing rubber.

The sealing glue used for the end sealant comprises a first component and a second component; the first component comprises 30-70 parts of E-51 epoxy resin, 50-100 parts of steel powder, 10-40 parts of silver powder and 10-25 parts of random carboxyl nitrile rubber by weight, and the second component comprises 10-30 parts of modified amine curing agent, 1-10 parts of fumed silica, 2-10 parts of 2,4, 6-tris (dimethylaminomethyl) -phenol and no more than 15 parts of silane coupling agent by weight; the proportion of the first component to the second component is (5-7): 1 by weight, and the first component and the second component are uniformly mixed to obtain the sealing adhesive.

The glue injection device comprises a glue injection port, an exhaust/observation hole and a glue injection control valve, and the glue injection funnel, the glue injection control valve and the glue injection port are also connected through steel wire hoses.

Filling adhesive to wrap the A component and the B component; the component A comprises, by weight, 80-100 parts of 828 epoxy resin, 10-30 parts of 678 reactive diluent, 10-30 parts of Qishi N toughening agent and no more than 2 parts of 550 defoaming agent, and the component B comprises, by weight, 30-60 parts of DL51 modified fatty amine curing agent, 3-8 parts of fumed silica and 1-5 parts of silane coupling agent, and the two are uniformly mixed to obtain the filling adhesive; the proportion of the A component and the B component is (2-4) to 1 by weight.

Compared with the prior art, the invention has at least the following beneficial effects: the invention provides a universal pipeline circumferential weld defect repairing device which comprises a steel sleeve, stress-dispersed fiber cloth, a filling colloid and a corresponding sealing structure, wherein the steel sleeve has the same external strength, the fiber cloth and the filling colloid are provided, and the corresponding sealing structure is provided, so that after a pipeline is repaired, the steel sleeve and a steel pipe to be repaired are in a sealing state, the integrity of the steel sleeve and the steel pipe is improved, and the strength of continuous, stable and reliable service is achieved; the device of the invention is adopted to vacuumize while injecting glue, improve the quality of filling glue between the steel sleeve and the pipeline to be repaired, avoid bubbles in the glue, arrange a glue injection port at the bottom of the steel sleeve, arrange a vacuumizing port/glue overflow port and an exhaust/observation hole at the top of the steel sleeve along the glue flow direction, and ensure that the glue has resistance in the injection process and overflows only when the gap between the steel sleeve and the steel pipe to be repaired is completely filled, thereby being beneficial to forming compact filling glue

By the technical system and the construction method of the composite epoxy steel sleeve, vacuum infusion and impregnation of the filling adhesive can be realized, fiber cloth is wound on the surface of a steel pipe with defects, the problems of embrittlement cracking, bubble curing and cavity filling of the traditional epoxy steel sleeve by resin are effectively solved, good matching between the composite epoxy steel sleeve and a steel pipe body is ensured, the annular load and the axial load borne by the pipe body defects and the circumferential weld joints are effectively shared, the pipe body defects and the circumferential weld joint defects are restrained from axially cracking, thereby achieving the purpose of repairing the defects of the pipe body and the girth weld, in a word, the method can provide a simple and easy epoxy steel sleeve repairing method with reliable performance, therefore, a product with reliable quality is provided for a pipeline manager, the repair construction quality is improved, and the aim of improving the management level of the integrity of the pipeline is fulfilled.

The invention also provides a vacuum composite dipping adhesive and an injection construction method, which ensure that the composite epoxy steel sleeve and the steel pipe body have good matching performance, effectively share the circumferential load and the axial load borne by the pipeline circumferential weld and restrain the circumferential weld defect from axially cracking.

Drawings

FIG. 1 is a schematic view of the system components of an epoxy steel sleeve for pipe rehabilitation;

FIG. 2 is a design drawing of an epoxy steel sleeve steel shell;

FIG. 3 is a pressure and pressure test curve of the pipeline after the epoxy steel sleeve is repaired;

FIG. 4 is a schematic diagram of hydraulic blasting of a rehabilitated pipeline;

in the attached drawing, 1-a pipeline to be repaired, 2-fiber cloth, 3-a steel sleeve, 4-a connecting bolt, 5-a positioning bolt, 6-end sealing rubber, 7-end sealing glue, 8-a glue injection port, 9-a vacuum pumping port/a glue overflow port, 10-an exhaust/observation hole, 11-a glue injection control valve and 12-a vacuum pumping control valve.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

The device for repairing the pipeline girth weld defects is shown in figure 1:

composite epoxy steel sleeve

1) Sleeve material and size design

a) The steel sleeve is made of a material which is the same as or higher than the steel grade of the pipeline 1 to be repaired, and for the high-steel grade pipeline, the wall thickness of a steel shell can be greatly reduced by adopting the high-steel grade sleeve, so that the weight is reduced, and convenience is brought to construction.

b) The wall thickness of the steel sleeve is designed according to the following formula:

in the formula: p-maximum allowable pressure for the pipe in Mega pascals (MPa);

d-inner diameter of the sleeve in millimeters (mm);

σ_s-a specified minimum yield strength of the sleeve material in megapascals (MPa);

phi-0.8 (bolting coefficient);

t_nwall thickness of the sleeve in millimeters (mm).

c) Inner diameter of steel sleeve

A gap is reserved between the inner wall of the steel sleeve and the outer wall of the pipeline to be repaired 1, fiber cloth 2 wound on the outer wall of the pipeline to be repaired 1 is arranged in the gap, the gap is convenient to install and can provide a smooth flowing space for injecting an adhesive, and the gap is preferably 20-30 mm.

d) Length of steel sleeve

The length of the steel sleeve can cover all the defect parts, the distance between the two ends of the steel sleeve and the outer side boundary of the defect is not less than 50mm, and the length of the sleeve is not less than 150 mm.

e) Distance between the connecting bolts 4

The minimum spacing of the connecting bolts 4 should meet the requirements of table 1.

TABLE 1 minimum bolt spacing

Nominal diameter d of boltB(mm)	12	16	20	22	24	27	30	36	42	48	56
												Minimum value L of bolt spacingmin(mm)	32	38	46	52	56	62	70	80	80	102	116

Maximum value L of bolt spacing_maxIt should not exceed the following calculation formula.

L_max＝3d_B+2δ_f(2)

In the formula: l is_max-maximum bolt spacing, mm;

d_B-nominal bolt diameter, mm;

δ_f-flange effective thickness, mm;

the diameter of the connecting bolt 4 is reasonably designed according to the bearing condition, and the requirement of maximum internal pressure bearing is met.

According to the material, the wall thickness, the diameter and the length of the steel sleeve 3 and the size design of the connecting bolt 4, the steel sleeve 3 aiming at the pipeline 1 to be repaired is reasonably selected.

2) Selection and requirement of the fiber cloth 2

The fiber cloth 2 is a reinforcement used by the invention and is a main bearing raw material of the composite epoxy steel sleeve, the preferred thickness of the invention is 0.5mm, and the surface density is 600g/m²Compared with the common glass fiber cloth, the 0 degree/90 degree bidirectional glass fiber cloth has the advantages that no fiber is crossed and woven to cause the bending deformation of the fiber, so the stress is more uniform, and the glue is easy to permeate; its tensile strength is 2200 ℃4000MPa, tensile elastic modulus of 60-90 GPa, weight of 400-600 g per square meter, width of 50-1500cm and length of 100 meters per roll.

3) Filled adhesive

The filling adhesive in the steel sleeve 3 is one of the keys of the repair technology, the filling adhesive is a composite material matrix used by the invention, the filling adhesive is used for transferring the load of the pipeline 1 to be repaired to the fiber cloth 2 used as a reinforcement and the material of the steel sleeve 3, and the filling adhesive is used for transferring the tensile stress, the compression stress, the bending stress and the shearing stress. At present, an epoxy adhesive is adopted at home and abroad, and has good mechanical properties, wherein the tensile strength is 40-90 Mpa, the compression strength is 40-100 Mpa, the shrinkage rate is 0.5-1.5%, and the bending strength is 50-150 Mpa; however, engineering practice shows that the existing epoxy steel sleeve has the problems of brittle cracking, cavities, solidified bubbles and the like of the filled epoxy adhesive material; therefore, the invention adopts fiber cloth to wind the defect part of the steel pipe 1 to be repaired in multiple layers, the low-viscosity (the viscosity is 190-350 cps) epoxy adhesive is vacuum impregnated and poured, and the comprehensive mechanical property after room temperature curing is better than that of the currently adopted filler epoxy adhesive at home and abroad; the problems of brittle cracking, cavities, solidified bubbles and the like found in the current epoxy steel sleeve are effectively avoided; the improved repair technology can effectively improve the repair quality and reliability of the epoxy steel sleeve.

The filling adhesive used by the invention comprises a component A and a component B, wherein the ratio of the components is shown in Table 2, and the weight ratio of the component A to the component B is (2-4): 1; the component A is transparent liquid, and has viscosity of 900-1400 cps at 25 deg.C and density of 1.1-1.2 g/cm³(ii) a The component B mainly comprises a curing agent and a silane coupling agent, is a blue clear liquid, has the viscosity of 5-20 cps at 25 ℃ and the density of 0.9-1.0 g/cm³(ii) a Mixing and stirring the two, and keeping the viscosity at 25 ℃ to be 190-350 cps; after curing for 48 hours at room temperature, the average value of the compressive strength is 104.8MPa (98.2-112.3 MPa) according to a GB1041 test, and the average value of the shear strength is 22.5MPa (20.0-24.2 MPa) according to a GB7124 test.

TABLE 2 weight ratio of the components of the filling adhesive material

The invention has made the vacuum cured composite material board, the glass fiber composite material cured at room temperature processes and tests GFRP according to GB3354, the tensile strength is 317.1MPa, process and test GFRP bending strength according to GB3356 and is 244.4 MPa; compared with the performance of the GFRP filling material adopted by other epoxy steel sleeve products, the performance of the GFRP filling material is improved by 2-3 times.

A vacuum system:

the working schematic of the vacuum-pumping device, the pipeline to be repaired and the composite epoxy steel sleeve is shown in figure 2.

1) End sealant

End sealing rubber 6 is arranged in a gap between the two ends of the steel sleeve 3 and the pipeline 1 to be repaired, and after the steel sleeve 3 is fastened, end sealing glue is adopted to seal the two ends of the steel sleeve 3; the end sealing adhesive prepared by the invention comprises a first component and a second component, wherein the proportion of the components is shown in table 3, and the weight proportion of the component A to the component B is (5-7): 1; the end part sealing adhesive has the advantages that the finger-touch drying time is 1-2.5 h under the room temperature condition (more than 15 ℃), the working temperature range is-60-150 ℃, the compression strength is 85-100 MPa, and the linear expansion coefficient is 15 multiplied by 10^-6and/K (close to steel).

TABLE 3 end sealant component weight ratios

2) Vacuum system integral seal improvement

In order to ensure that the steel sleeve 3 does not generate bubbles, cavities and other defects after being filled with the adhesive and cured, the method is one of the key links of the invention, the vacuum impregnation and filling of the low-viscosity epoxy adhesive must meet the vacuum condition, the glue filling process parameters are crucial, besides the epoxy steel sleeve end sealant, the method adopts the industrial raw adhesive tape, the vacuum sealing adhesive tape and the rubber tape to integrally improve and promote the sealing property of the vacuum system, so that the field workload can be reduced, and the field can be greatly improved to quickly reach the vacuum filling condition.

Industrial crude rubber belt (bolt seal)

The steel sleeve 3 is provided with a glue injection port 8, a vacuum pumping port/glue overflow port 9 and an observation port 10; the glue injection port 8, the vacuumizing port/glue overflowing port 9 and the observation port 10 are all provided with standard joints, the joints of the glue injection port 8, the vacuumizing port/glue overflowing port 9 and the observation port 10 are all in threaded connection with the steel sleeve 3, and the joints are all sealed by raw rubber belts.

The vacuum sealing adhesive tape is adopted to clamp the vacuum sealing adhesive tape between the binding surfaces of the upper steel shell and the lower steel shell, and meanwhile, when the steel sleeve is vacuumized and is poured with an adhesive, the vacuum sealing adhesive tape with any shape and size can be cut to directly block the cleaned air leakage part, and the effect is good.

The end part of the sleeve is sealed by matching end part sealing rubber 6 with sealant, an assembly gap of 10-15 mm exists between the inner diameter of the steel sleeve 3 and the whole circumferential direction of the outer wall of the pipeline 1 to be repaired, 1141 rubber belts with the width of 25mm and the thickness of 3mm are cleaned, and 4 layers are adhered to the set position of the steel pipe to be repaired by 801 glue for ensuring the uniform construction of the sealant at the end part of the steel sleeve 3.

Glue injection device:

the glue injection device comprises a glue injection funnel, a bracket and a steel wire hose, wherein the glue injection funnel is at least 1m higher than the top of the pipeline to be repaired during construction, the glue injection process is controlled within 30min, the vacuum is pumped to-0.08 to-0.09 MPa, and glue injection is performed after the vacuum degree is stable; in order to ensure that the curing effect of the filled adhesive is good, a heating belt is adopted to heat the adhesive to 60 ℃ for curing for 8 hours.

The construction process comprises the following steps:

the process flow of the compound epoxy steel sleeve glue injection developed by the invention is as follows: performing sand blasting treatment on the outer surface of the steel pipe 1 to be repaired and the inner surface of the steel sleeve → installing a vacuum-pumping joint, an injection joint, a vacuum observation screw and a positioning bolt 5 → winding glass fiber cloth on the outer surface of the defective part of the steel pipe 1 to be repaired → adhering a rubber belt at the end part of the steel pipe sleeve → adhering a vacuum sealing adhesive tape at the joint of the steel connecting bolt 4 → assembling the two semi-cylindrical sleeves → adjusting the positioning bolt 5 to the required size to gradually tighten the connecting bolt 4 → connecting a vacuum-pumping device → connecting an injection device → vacuumizing to-0.08 to-0.09 Mpa till the vacuum degree is stable → mixing the adhesive and stirring uniformly, pouring the mixture into the injection device → injecting the adhesive, keeping the vacuum, observing that the adhesive has a height of 90-120 mm in the vacuum conduit → closing an injection valve and stopping the vacuum-pumping → curing the adhesive.

1) Surface treatment

The outer surface of the pipeline 1 to be repaired and the inner wall of the steel sleeve 3 are treated by adopting manual tissue paper polishing, a manual steel wire brush, sand blasting or an electric steel wire wheel; the surface cleaning length of the pipeline 1 to be repaired is longer than that of the steel sleeve 3, and an operation space is reserved for sealing the end part of the steel sleeve 3; the surface treatment quality is required to reach St3 grade in GB/T8923.1, and the set requirement of the anchor line depth is met, the preferred anchor line depth of the invention is 40-100 mu m, which is beneficial to enhancing the bonding force between the adhesive and the steel surface; after cleaning, cleaning sand particles with a clean brush, scrubbing the surface with industrial grade acetone with clean cotton yarn or absorbent cotton, then uniformly brushing a layer of KH55O acetone solution with a brush, drying, and keeping dry and clean.

2) Fiber cloth pre-laying

The invention adopts bidirectional glass fiber cloth to wind the defective part of the pipeline 1 to be repaired, the total thickness does not exceed the clearance between the steel sleeve 3 and the outer wall of the pipeline to be repaired, and the invention preferably adopts glass fiber or carbon fiber as the fiber cloth material.

3) Mechanical mounting of steel sleeves

Before the steel sleeve 3 is arranged on the pipeline 1 to be repaired, brushing glue on the rubber belt and winding the rubber belt at two ends of the installation position of the steel sleeve, wherein the winding thickness of the rubber belt is larger than the gap between the outer wall of the pipeline 1 to be repaired and the inner wall of the steel sleeve; placing the two semi-cylindrical sleeves on the pipeline 1 to be repaired, installing vacuum sealing adhesive tapes on the binding surfaces of the upper steel sleeve and the lower steel sleeve before fastening the connecting bolt 4, screwing the positioning bolt 5 into the positioning threaded hole, and propping the outer wall of the pipeline 1 to be repaired by the positioning bolt 5 to realize the adjustment of the gap between the outer wall of the pipeline 1 to be repaired and the inner wall of the steel sleeve 3, wherein the gap between the inner wall of the steel sleeve 3 and the outer wall of the pipeline to be repaired is uniformly adjusted, and the maximum value of the gap is not more than 3 mm; and (3) placing the pipeline defect to be repaired at the length center of the steel sleeve 3, wherein the distance from the tail end of the steel sleeve 3 to the outer side boundary of the defect is not less than 50mm, and the length of the sleeve is not less than 150 mm.

4) Glue injection system and vacuum system assembly

According to the figure 1, a vacuum pump, a vacuumizing control valve 12, a tee joint, a pipeline, a vacuumizing joint, a glue injection joint and a glue injection funnel are connected, and the connection tightness is ensured; when the glue injection port 8 is connected, the horizontal direction of the pipeline is considered, if the inclination is larger, the glue injection port with the lowest horizontal position of the steel sleeve 3 is selected as shown in fig. 1, and an unused glue injection port is sealed by a sealing head; two vacuum pumping ports/glue overflow ports 9 are arranged, and 1 is respectively arranged at two ends of the top of the steel sleeve 3.

5) Vacuum forming and maintaining

After the two ends of the steel sleeve 3 are sealed by adopting the end sealant 7, starting a vacuum pump to pump vacuum, checking that the vacuum degree reaches-0.08 to-0.09 MPa, and maintaining the pressure for 10 minutes after the vacuum pump is closed to reduce the vacuum degree to be less than 0.001 MPa.

6) Glue mixing and injecting process

And uniformly mixing the component A and the component B of the filling adhesive, injecting the mixture into an injection funnel, and opening an injection control valve to realize injection under the condition that a vacuum pump is started and the vacuum degree is ensured to be higher than-0.08 MPa. And after the glue injection is finished, the adhesive is cured by adopting a heating means. Preferably, the heating is carried out at 60 ℃ for 8 hours.

7) Anti-corrosion treatment

After the solidification is finished, the glue injection joint and the glue overflow joint are detached and sealed by using end sockets, the redundant parts of the positioning bolts 5 and the observation hole bolts are cut off, and then the anticorrosion operation is carried out. According to the invention, corrosion prevention is preferably carried out by adopting a mode of matching a viscoelastic body with a cold winding belt, and the condition that no leakage point is detected by electric spark is qualified.

The device for repairing the pipeline girth weld defects by using the epoxy steel sleeve and the process application repairing example are provided.

The pipe section to be repaired and the defect information are shown in table 4:

TABLE 4 pipe information to be repaired

1. Steel sleeve

The specification information of the steel sleeve is shown in table 5, and the form schematic diagram is shown in fig. 1:

TABLE 5 Steel Sleeve Material information

Material of	Outer diameter (mm)	Wall thickness (mm)	Length (m)	Bolt diameter (mm)	Bolt spacing (mm)
						16Mn	315	5.6	1.5	20	100

2. Surface treatment of pipe to be repaired

And treating the surface of the pipeline to be repaired and the inner wall of the steel shell by adopting sand blasting and artificial tissue polishing means. The sand grains are made of No. 60 carborundum, the sand blasting pressure is kept at 0.8-1.0 MPa, the sand blasting surface and the sand grains are kept dry, after sand blasting is finished, the sand grains are removed by a clean brush, the surface cleaning length of the pipeline 1 to be repaired exceeds 20cm of each of two ends of the steel sleeve 3, an operation space is reserved for sealing the end part of the steel sleeve 3, the processing quality of the outer surface of the pipeline 1 to be repaired reaches St3 grade in GB/T8923.1, and the anchor line depth is 60 +/-10 mu m; after polishing, impurities such as sand grains and the like are removed by using a clean brush, the surface is scrubbed by using clean cotton yarn or absorbent cotton dipped in industrial-grade acetone, and a layer of KH55O acetone solution is uniformly and quickly brushed by using the brush for airing for later use, and the drying and cleaning are kept.

3. Fiber cloth pre-laying

The glass fiber cloth with the thickness of 0.5mm and the surface density of 600g/m and the width of 1.3m is wound by taking the defect as the center position, and 25 layers are wound.

4. Steel sleeve mounting

Before steel sleeve 3 is arranged in and is waited to restore on the pipeline, brush the glue for the rubber strip and twine it in the both ends of steel sleeve mounted position, rubber strip winding height is greater than the clearance of waiting to restore 1 outer wall of pipeline and 3 inner walls of steel sleeve, arrange steel sleeve 3 in on the pipeline, before fastening connecting bolt 4, install vacuum seal raw rubber area on the faying face of two flanges, be provided with a plurality of hoop evenly distributed's positioning screw hole on the telescopic both ends wall of steel, with positioning bolt 5 screw in positioning screw hole, the adjustment of the clearance of waiting to restore 1 outer wall of pipeline and 3 inner walls of steel sleeve is realized in waiting to restore the pipeline outer wall through positioning bolt 5 top, actual measurement installation maximum error is 1mm, will wait to restore the pipeline defect and arrange 3 length central points in and put in steel sleeve, and from the centre to both sides in proper order tighten all connecting bolt 4.

5. Assembly of filling line

The vacuum pump, the vacuumizing control valve 12, the tee joint, the pipeline, the vacuumizing joint, the glue injection joint and the glue injection funnel are connected, and the connection tightness is ensured; when the glue injection joint is connected, the glue injection port 8 in the center of the bottom of the steel sleeve is selected to inject glue to the pipeline to be repaired basically horizontally, and the glue injection port which is not used is sealed by an end socket.

6. Formation of vacuum system

Coating end part sealant on two end faces of the steel sleeve 3, after sealing, starting a vacuum pump to vacuumize, checking that the vacuum degree reaches-0.098 MPa, and keeping the pressure for 10 minutes after closing the vacuum pump to reduce the vacuum degree to be not more than 0.001 MPa.

7. Glue mixing and injecting process

The formula of the filling adhesive is shown in table 2, the component A and the component B are mixed and stirred uniformly according to the weight ratio of (2-4) to 1, the mixture is injected into an adhesive injection funnel, and an injection control valve is opened to realize adhesive injection under the condition that a vacuum pump is started and the vacuum degree is kept.

After the glue injection is finished, heating is carried out by adopting a heating belt, and the heating is carried out for 6 hours at the temperature of 60 ℃.

The repairing effect is as follows:

after the repair is finished, performing a full-size hydraulic blasting verification test on the repaired pipeline; the hydraulic blasting pressurization scheme is shown in table 6, the pressurization curve is shown in fig. 3, and it can be seen that the pressure of the repaired pipeline is maintained for 1 hour at the design pressure and 1.25 times of the design pressure, the pressurization curve is stable, no leakage and microleakage occur, the final blasting pressure is 18.6Mpa, the theoretical blasting pressure is 17Mpa, and the pipe body part with a flawless blasting opening is shown in fig. 4.

TABLE 6 scheme for testing pressure rise and pressure maintaining of samples

Step (ii) of	Content providing method and apparatus	Time to steady voltage	Remarks for note
				1	0.8 times the design pressure	10 minutes	Pressure of operation in situ
2	Design pressure	1 hour	Verifying repair reliability
				3	1.25 times design pressure	1 hour	Verifying repair safety factor
4	Boosting until blasting	/	Whether to recover the pressure bearing capacity of the pipeline

The glue injection device can also adopt a glue gun or a glue injection machine.