TEST RESULTS OF THE REINFORCING SLEEVE-PROTECTOR UBMT

Astrakhan, September 21, 2016 - September 29, 2016

CONTENTS

GENERAL PROVISIONS 
REGULATORY DOCUMENTS
TEST PREPARATION
MAIN TESTS
ADDITIONAL TESTS
TEST RESULTS

GENERAL PROVISIONS 

   The reinforcing sleeve-protector with concrete banding UBMT is used to repair defects of a corrosion and mechanic nature at straight and curved sections of coated pipelines of various purpose, including underwater ones, without the need to cut out defect parts and discontinue operation.
   In terms of design, the protector is a composite reinforcing sleeve with additional protection in the form of a concrete band in an irremovable metal casing.

UВMT’s external view for a straight section

A test program for the reinforcing sleeve-protector was developed during the planning and preparation for tests. It takes into account the conditions and specifics of operation of sea underwater pipelines. 

REGULATORY DOCUMENTS

• Test methodology program for the reinforcing sleeve-protector with a concrete band:
• Sea underwater pipeline classification and construction rules, RMRS, 2016
• GOST R 54382-2011 Underwater pipeline systems. General technical requirements
• RD 03-606-03 Visual and measurement testing instruction
• GOST R EN 13018-2014 Visual testing. General provisions
• GOST R 55724-2013 Non-destructive testing. Welded connections. Ultrasound method
• PB 03-593-03 Rules of organizing and performing the acoustic emission testing of vessels, apparatus, boilers and process pipelines
   

TEST PREPARATION

   The test preparation and performance works of the reinforcing sleeve-protector with concrete banding UBMT were carried out in the territory of, and by experts of “Multi-Business Company “KASKAD”, LLC (village of Karagali, Astrakhan Oblast). During the test preparation, 2 prototype samples were made from a steel seamless concrete coated pipe 406.4х17,5 Х60 (coil’s length without ends is 2,745 mm) and ellipsoidal end DS 406,4(36К65)-28.
   The pipes’ coil ends were treated for welding in accordance with GOST 14776 requirements. Test benches were equipped with three connectors for water input, connecting a manometer (measurement limits – 400 kp/cm²), connecting a pressure sensor (measurement limits – 250 kp/cm²) and removing air. 
    Artificial defects in the form of a groove were mechanically made on the internal surface of the samples. 

Experts of the non-destructing testing laboratory of LLC «NTC «NEFTEGAZDIAGNOSTIKA» performed the following non-destructive tests (visual, measurement and ultrasound ones) during the production of the prototype samples:

• Visual testing and measuring the actual dimensions of the artificial defects.
• Visual and measurement testing of the ends’ assembly for welding. 
• Visual, measurement and ultrasound testing of welding joints of ends connections. 
• Visual, measurement and ultrasound testing of connectors’ welding.  

Ультразвуковой контроль сварных соединений образца №1

After the artificial defects were prepared and the ends were installed on Sample No. 2, a reinforcing sleeve-protector with concrete banding UBMT was assembled. The assembly was supervised by experts of LLC «NTC «NefteGazDiagnostika».

Steel seamless CWC pipe 406.4х17,5 steel Х60.	Pipe with welded ends.
Surface preparation for the installation of a sleeve Smart Lock/UKMT (decontamination, degreasing).	Components for an adhesive compound.
Smart Lock/UKMT sleeve.	Smart Lock/UKMT's fiberglass insert.
The insert is prepared for installation (internal surface decontamination, degreasing).	Application of the adhesive component.
The insert is installed.	The sleeve Smart Lock/UKMT is installed.
Sample No. 2 with the sleeve Smart Lock/UKMT installed in the artificial defect area.	Installation of the UBMT sleeve-protector.
Installation of the UBMT sleeve-protector.	Installation of the UBMT sleeve-protector.
Sample No. 2 with a connected hose to pump a concrete mixture.	Concrete mixture treatment plant.
Mixture going out through valves at the top of the sleeve.	Sample No. 2 with the installed repair construction UBMT.

MAIN TESTS

Sample No. 1	Sample №2

   As per the test program, the positive results mean the absence of working fluid leaks (pressure drop on the bench) through the sleeve or protective coating within a holding time of 24 hours at the maximum pressure of Рисп=19,7 MPa (197 kg/cm²) and of 12 hours at a pressure of Рисп=15,4 MPa (154 kg/cm²). The acoustic emission testing results are provided in Annex 1 (Protocols АЭ-009-10-2016, АЭ-009-11-2016).
  During the tests and based upon the results of the acoustic emission testing of the test process, the committee introduced changes into the pressure during the holding times and into the duration of a holding time at a constant pressure. Changes into the test diagram (pressure rise section) are introduced following the test results of Sample No. 1

Плановый график изменения давления при испытании.	Фактический график изменения давления при испытании образца №1

The tests were carried out in the following order: 

1.       Testing Sample No. 1 (without the sleeve).
1.1.    The sample is installed on a bench.
1.2.    A water hose is connected. Water is poured in. 
1.3.    A manometer and a pressure transducer are installed. Remaining air is blown off. 
1.4.   Acoustic emission transducers are installed on the sample. The acoustic emission transducers and the pressure transducer are connected to the acoustic emission system. 
1.5.  Hydraulic test up to 8 kp/cm², performance check and adjustment of the acoustic emission system. 
1.6.  Tests: pressure rise, holding, pressure decrease. The test process was recorded in on-line 
mode with a video camera and a remote display. The bench’s condition was monitored with the use 
of the acoustic emission method for the purpose of recording the crack formation and at the same 
time recording the current pressure in the sample. 
1.7.    The sample is inspected after the pressure drop, the damages are recorded. 
2.       Testing Sample No. 2 (with the sleeve).
2.1.    The sample is installed on a bench.
2.2.    A water hose is connected. Water is poured in.
2.3.    A manometer and a pressure transducer are installed. Remaining air is blown off.
2.4.    Acoustic emission transducers are installed on the sample. The acoustic emission transducers and the pressure transducer are connected to the acoustic emission system.
2.5.    Hydraulic test up to 8 kp/cm², performance check and adjustment of the acoustic emission system.
2.6.    Tests:
2.6.1. Pressure rise. The test process was recorded in on-line mode with a video camera and a remote display. The bench’s condition was monitored with the use of the acoustic emission method for the purpose of recording the crack formation and at the same time recording the current pressure in the sample.
2.6.2.  Holding at a pressure of 231 kp/cm² within 24 hours. Acoustic emission testing.
2.6.3.  The pressure is dropped to 160 kp/cm² and holding at a pressure of 160 kp/cm²  within 19 hours. Acoustic emission testing.
2.6.4.  The pressure is dropped to 0.
2.7.     The sample is inspected after the pressure drop, the damages are recorded.

Test results of Sample No. 1

The tests of Sample No. 1 have the following results:

1. There was identified a working liquid leak from the Sample through the concrete coating on each end.
2. There was identified no leak through circular welds and connector welds. 
3. There was identified no leak along the metal polymer border. 

 

Conclusion

When carrying out the hydraulic tests of Sample No. 1, there occurred a depressurization of the Sample and a pressure drop during holding at a constant pressure within 2 minutes after the excessive pressure of 213.1 kp/cm² was reached. 

Actual pressure change diagram during the tests of Sample No. 2

Pressure rise section

Test results of Sample No. 2

The tests of Sample No. 2 have the following results:

1. There was identified no leak.
2. A pressure drop during holding at a temperature of 230 (-8) and 160 (-3) kp/cm² are due to the daily temperature difference.

 

ADDITIONAL TESTS

Upon completion of the main tests, it was decided to carry out tests of Sample No. 2 at the maximum allowable testing pressure of 400 kp/cm².

Pressure change diagram during the additional tests of Sample No. 2.

Upon completion of the pressurization and pressure drop to 0, a visual inspection of Sample No. 2 was carried out. There were identified no leaks from under the sleeve and the insulation coating.

TEST RESULTS 

There was a depressurization during Sample No. 1’s holding at a pressure of 213 kp/cm² . There was an increase of the number of impulses and the activity of acoustic emission signals with an amplitude exceeding 100 dB immediately prior to the destruction. 
When the pressure reached 114.0 kp/cm², there was registered the generation of acoustic emission sources when testing Sample No. 1 which points to the fact that it was the beginning of a plastic deformation in the defect area. 
During the tests the acoustic emission activity was registered in the pressure change (increase) periods. 
The depressurization of Sample No. 1 took place in a pressure holding period at 213 kp/cm² which exceeds the testing pressure in the pipeline by 8%. 

1. When testing Sample No.1, critically active acoustic emission sources were registered since the time when the pressure reached 140 kp/cm². Critically active acoustic emission sources are registered only within the periods when the testing pressure is changed, but, what is very important, at the time of pressure holding. A defect is developed at pressures compatible with the working pressure in the pipeline (154 kp/cm²).
2. There was a liquid leak during the depressurization of Sample No. 1 along the border – the anti-corrosion insulation – the concrete coating. It points to the fact that the anti-corrosion insulation is destroyed. 
3. When testing Sample No. 2, the absence of any registered critically active acoustic emission sources points to the fact that there was no plastic deformation, nor any cracks were formed in the artificial defect area, which confirms the high reliability of the repair method with the use of the reinforcing sleeve-protector UBMT and a significant degree of safety of the structure. 

When carrying out the hydraulic tests of Sample No. 2, there was registered no pressure drop at holding within 24 hours at a pressure of 231 kp/cm² and within 19 hours at a pressure of 160 kp/cm². The Sample passed the test. And there were registered no acoustic emission sources of the 4th hazard class (catastrophically active ones) and the 3rd hazard class (critically active ones). No leaks were identified either. 

When carrying out the additional tests of Sample No. 2, when increasing the pressure and holding it at 400 kp/cm², there were identified neither any pressure drop, nor any leaks.