Acoustic emission detection

Typical engineering

1、 Acoustic emission detection

Acoustic emission detection technology has significant practical value in equipment operation status monitoring and production safety warning, and can be widely applied in fields such as petrochemical, aerospace, material experiments, and transportation. We can dynamically monitor the occurrence and development of material defects. For example, we were commissioned by Henan Provincial Boiler Inspection to conduct hydraulic AE testing on 12 2000m3 spherical tanks of Shandong Mingrunchang Chemical Co., Ltd., and conducted TODF re inspection on the defects. At the same time, we used conventional ultrasond to determine depth, length, and height to evaluate the defects, ensuring the safe use of the spherical tanks. Acoustic emission testing also creates huge economic benefits for enterprises, without the need for replacement, cleaning, steaming, scaffolding, polishing, and greatly shortening the inspection cycle.

Three 600&times imported from Canada commissioned by Yuehua Petrochemical Company; 100× The 23000mm 100at high-pressure nitrogen cylinder underwent in-service pressure boosting acoustic emission testing. It took eight days to complete the pressure boosting testing one by one and then put it into normal operation. Without affecting the normal production of the entire factory, the inspection tasks for three high-pressure containers were completed.

The company has conducted a new technology combining acoustic emission dynamic inspection and ultrasonic quantitative evaluation on hundreds of spherical tanks, pressure vessels, reaction kettles, and high-pressure gas cylinders, which has significant social and economic benefits. Important projects are listed as follows:

In December 1987, during the water pressure test of the 1 # 2000 carbon four spherical tank at Shanghai Jinshan Petrochemical General Plant after routine NDT inspection, AE monitoring was conducted on the remaining large defects of incomplete welding. After no expansion of the defects, it was safely put into use.

In July 1988, at the Chemical Plant of Shanghai Gaoqiao Petrochemical Company, a 401-1 # 400 m3 spherical tank was comprehensively inspected and evaluated. Two remaining 1.5 m long and 2 mm high incomplete welds were subjected to acoustic emission inspection under water pressure, proving that the defects did not expand before being put into use.

In June 1990, the chemical plant of Shanghai Gaoqiao Petrochemical Company conducted water pressure acoustic emission monitoring on the spherical tank again without any defects, and the signal was immediately put into use.

In June 1990, the ABS reactor at the Chemical Plant of Shanghai Gaoqiao Petrochemical Company was put into use after direct water pressure acoustic emission monitoring without active AE signals.

In August 1987, Yuehua Storage and Transportation Company conducted water pressure acoustic emission monitoring on five containers, including liquid hydrocarbons, and conducted NDT inspection after discovering active sources.

In February 1991, Yuehua Storage and Transportation Company conducted water pressure acoustic emission monitoring on 10 liquid hydrocarbon and other containers.

In October 1995, the Chemical Plant of Lanzhou Petrochemical Complex conducted acoustic emission inspection and evaluation on three ultra-high pressure reaction kettles.

In October 1996, Yueyang Yingshan Petrochemical Company successively carried out inspections on three unitsΦ 2600× 100× Hydroacoustic Emission Inspection and Evaluation of 23000 High Pressure Nitrogen Gas Cylinders in Service,

In October 1996, Yueyang Petrochemical Nylon Factory conducted acoustic emission testing on two sets of 300 m3 and 400m3 insulated ammonia balls.

In December 1996, Yueyang Petrochemical Nylon Factory conducted a pneumatic acoustic emission inspection and evaluation of four multi-layer ammonia synthesis towers.

In October 1990, two 400m3 ammonia spherical tanks with insulation layer were inspected and evaluated by acoustic emission at Anhui Tongling Phosphoan Compound Fertilizer Plant.

In December 1996, at Anqing Petrochemical Fertilizer Plant, two acoustic emission activity sources were found in the water pressure AE monitoring of the 5 # 1000m3 spherical tank after NDT inspection. During NDT re inspection, it was found that the transverse crack was 30 mm long and 7 mm deep. After repair, the safe operation of the spherical tank was ensured.

In November 2015, the water pressure AE monitoring of 12 2000m3 liquefied balloon tanks of Shandong Mingrunchang Chemical Co., Ltd. found 8 acoustic emission active sources, and TOFD re inspection found severe cracks with a length of 220 mm and a depth of 8mm. After repair, the safe operation of the spherical tanks was ensured.

2、 Spherical tank

The company has purchased 2000m3, 31000m3 liquefied balloon tanks from Shanghai Petrochemical General Plant; Multiple 400m3 and 120m3 spherical tanks for propylene and liquefied petroleum gas; 1000m3 spherical tanks from Guangzhou Petrochemical Plant 605606 and 1000m3 spherical tanks from Ethylene Plant; Yueyang Petrochemical General Factory Supply and Marketing Company Nylon Factory 1 #~9 # 1000m3400m3300m3200m3 Spherical Tanks and Rubber Factory Multiple 1000m3400m3 Spherical Tanks; 400m3 spherical tanks 605 and 606 of Zhenhai Petrochemical Plant; 400m3 spherical tank at Yumen Refinery; Gaoqiao Petrochemical Company 401- (1), (2), (4) and 2801- (1) 400m3 spherical tanks; 400m3135m3 (1 #, 2 #, and 3 #) oxygen tanks at Shanggang No.1 Plant; Three 1000m3 spherical tanks, 750m3 propylene spherical tanks, 200m3 oxygen spherical tanks, and 113m3 spherical tanks from Yangzi Petrochemical Company; 1000m3400m3130m3120m3 spherical tank from Qilu Petrochemical Company; Anqing Petrochemical Plant, 1000m3 spherical tank; 600m3 liquid ammonia spherical tank at Xingping Fertilizer Plant; Multiple 400m3 spherical tanks at Tongling Phosphorus and Ammonia Plant; Maoming Petrochemical Company has conducted multiple quantitative inspections and evaluations on 2000m3 propylene spherical tanks and 1000m3 spherical tanks, as well as multiple 125m3 oxygen spherical tanks from Baotou Steel Company. This has enabled the inspection spherical tanks to be safely put into operation as soon as possible, achieving significant social and economic benefits. For example, the 1 # and 200m3C4 spherical tanks at Shanghai Petrochemical Plant have been discontinued for more than a year and will be put into operation after half a month of quantitative inspection and minor repairs; Three 1000m3 spherical tanks of Yangzi Petrochemical Company have been put into operation after ten days of acoustic emission and quantitative evaluation; Nine 1000m3 spherical tanks from the Supply and Marketing Company of Yueyang Petrochemical General Factory and several 400m3 spherical tanks from the Rubber Factory were the first batch of 15MnV steel large spherical tanks in China in the early 1970s. Welding defects and geometric defects in the welds were severe. Over the years, they have undergone multiple quantitative inspections and repairs to ensure their safe operation to this day.

3、 Large pressure vessels and pipelines for catalytic cracking.

Catalytic cracking regenerator settler, tricyclone and Ф The 2200mm flue gas pipeline not only has a huge size (Φ 9600× 26× 30000), but also is lined with expensive tortoiseshell mesh insulation layer. Due to the heavy and diversified nature of raw materials, dew point corrosion often occurs on the inner wall, causing a large number of serious stress corrosion cracks, seriously affecting the safe operation of the equipment; Is it allowed to continue using expensive equipment due to the requirement of increasing internal pressure and temperature during technological transformation? In response to the above two reasons, it is proposed to develop the following new technologies;

One is to develop a new non-destructive testing technology for quantitatively detecting stress corrosion cracks on the inner wall from the outer wall; We have developed a company specific point focused K1 probe and, based on the characteristics of stress corrosion network cracks, used a multi-directional scanning method to determine the position of stress corrosion cracks, and quantitatively measured the height of the cracks themselves using endpoint diffraction waves.

Secondly, in response to the increasing pressure and temperature parameters and the current lack of stress corrosion and corrosion fatigue life prediction technology, a conservative engineering calculation method for life prediction is proposed, and a quantitative calculation evaluation method is developed to reverse the system pressure vessel and pipeline defect evaluation method VPDA-1999. The use of this complete set of new technology has been successively applied to Tianjin RefineryΦ 7200 reactor andΦ 9600 regenerator; Regenerator and reactor of Yumen Refinery; Anqing Petrochemical PlantΦ 9600 Regenerator andΦ 7200 sedimentation tank; Jiujiang Petrochemical Plant Heavy ExpeditionΦ 9400× 24× 28000 Regenerator,Φ 6300× 18× Quantitative inspection and evaluation of 21000 settler, three rotators, and flue gas pipelines, Guangzhou Petrochemical Plant Heavy Expedition WorkshopΦ Regenerator for 9600,Φ Quantitative inspection and evaluation of 7200 settlers, three rotors, and flue gas pipelines. Both have achieved significant social and economic benefits. The user certificate issued by Guangzhou Petrochemical Factory shows that this alone has brought a direct economic benefit of 3.2925 million yuan and an indirect economic benefit of 16 million yuan to the factory. 4、 Quantitative inspection and evaluation of high-pressure and ultra-high-pressure vessels.

High pressure and ultra-high pressure vessels are the core equipment of petrochemical and fertilizer plants, with high safety requirements and expensive prices. The use of new technologies for testing and quantitative evaluation has enormous social and economic benefits. The engineering projects implemented by Huaxia Company include:

Six 1500 atmospheric pressure ultra-high pressure polyethylene reactors from Lanzhou Petrochemical Company (imported from the UK);

Xiangjiang Nitrogen Fertilizer PlantΦ 1000mm320 atmospheric pressure ammonia synthesis tower (imported from Czech Republic);

Yuehua Nylon Plant's 320at ammonia synthesis tower, ammonia separator, and five section and six section buffers for 1 #, 2 #, and 3 # high-pressure machines;

Yuehua Rubber Factory F501c. d high-pressure kettle;

Zhuzhou Chemical Plant High Pressure Polymerization Kettle;

Huainan Fertilizer Plant High Pressure Reactor;

320at ammonia synthesis tower of Xingping Fertilizer Plant;

High pressure carbon black washing tower imported from Japan by Zhenhai Petrochemical Plant;

Luoyang Refinery High Pressure Nitrogen Tank;

Hefei Casting and Forging Factory 10 #, 11 #, and 12 # high-pressure heat accumulators;

1000at artificial crystal ultra-high pressure reactor produced by Beijing Heavy Machinery Factory

; Shanghai Gaoqiao Petrochemical Company Hydrogenation Reactor;

Nanjing Yangzi Petrochemical Company Aromatics PlantΦ 4400× 50× 9850 platinum reforming reactor;

Shanghai Petrochemical Polyester FactoryΦ 2600× 65/125× 11460 hydrogenation reactor;

High pressure nitrogen cylinder at Dongfanghong Refinery of Beijing Yanshan Petrochemical Company;

Quantitative inspection of high-pressure nitrogen oxygen bottles at Yueyang Yingshan Petrochemical Company.

5、 Boiler drum.

123C synthetic ammonia waste heat steam boiler imported from the United States by Sichuan Chemical Plant;

Tianjin Refinery 3 # Boiler Upper and Lower Steam Drums and Steam Generator Upper Steam Drums (Φ 1400× 6000);

4 # boiler drum of Yunnan Yangzonghai Power Plant;

1 # and 2 # boiler drum of Hegang Company;

Shanghai sulfuric acid horizontal quick drying boiler;

13 sets of high-pressure steam heaters in Qihua Thermal Power Plant

Yuehua General Factory Rubber Factory Waste Heat Boiler, etc.

6、 Quantitative inspection and evaluation of heat exchangers, towers, and reactors for other pressure vessels.

Main inspection and evaluation projects:

Tianjin Refinery liquefied gas desulfurization tower: dry gas desulfurization tower, solvent regeneration tower, deethanizer tower, T301 desulfurization tower, T303 regeneration tower, etc;

Propylene polymerization kettle of Shanghai Petrochemical General Plant Plastic Plant: 10 # 15 # 30 # 35 # spinning and defoaming tank of Vinylon Plant, multiple YL733A pressure regulating tanks, and 18 spinning and defoaming barrels; 30 heat exchangers, storage tanks, etc. in chemical plants;

Shanghai Gaoqiao Petrochemical Company: imported 4 ABS reactors, deethanizer, depropanizer, etc;

The aldehyde washing tower of Yuehua Rubber Factory includes 10 condensers, 7 monomer heat exchangers, butadiene benzene extraction and distillation tower, T202 distillation tower, T305 absorption tower, depropanizing tower, T306 analysis tower, deethanizer tower, deprropene tower, deethanizer tower reflux tank, depropanizer tower top reflux tank, debutanizer tower, butadiene distillation tower, butadiene extraction tower, butadiene evaporation tower, K1 depropanizer tower, butane water washing tower, 205a butadiene distillation tower, evaporation tower, T211 tower, H202 storage tank, T210, T211 butadiene water washing tower, R204, R202a, R202b inspection and evaluation, 5 alkyl aluminum tanks, active aluminum tanks; 12 butadiene reflux tanks, 13 ammonia liquid separators, 8 vertical ammonia condensers, etc., butane washing tower, extraction tower, steam tower, T207 butadiene distillation tower, T208 dehydration tower, T212, T213 extraction tower, steam tower,Φ 1600× 40000 distillation tower, analytical tower, etc.

Yuehua Polyester Plant 1 #, 2 #, 3 #, polymerization kettle; Reaction kettle, depolymerization kettle, impregnation kettle, carbon dioxide absorption tower, 4 buffer tanks, separator; 8 storage tanks, etc;

Yumen Refinery Coking Tower, etc;

Anqing Petrochemical Plant Coking Tower, etc;

Fushun Petroleum Third Plant Coking Tower, etc;

1 #, 2 #, 3 #, 4 # oxygen storage tanks, 1 #, 3 # steam collection drums, etc. of Hegang Company; Hangzhou Refinery 17 distillation kettles, etc;

15 absorption towers, nitrogen tanks, etc. at Luoyang Refinery;

Inspection and evaluation of 21 heat exchangers and 23 pressure vessels at Guangzhou Petrochemical Plant;

120 pressure vessels at Maoming Petrochemical Ethylene Plant;

57 pressure vessels, including the EDC recovery tower in the chlor alkali plant of Qilu Petrochemical General Plant.

7、 New Technology and Application of Quantitative Inspection and Evaluation for Pressure Pipelines in Service

The frequent occurrence of in-service pressure pipeline accidents and the development of new quantitative inspection and evaluation technologies have received widespread attention and attention nationwide. However, in order to achieve rapid quantitative testing of pipelines, existing non-destructive testing technologies must make the following major breakthroughs:

(1) Breaking through the limitations of ultrasonic methods that cannot detect small diameter thin-walled pipelines (large blind spots and large curvature cause ultrasonic scattering, greatly reducing sensitivity),

(2) Breaking through the limitation that magnetic particle testing can only detect surface defects can replace the labor-intensive, low efficiency, long cycle, and high cost of conventional radiographic testing; Low detection rate for dangerous surface defects; Unable to achieve in use detection; Disadvantages such as inability to provide quantitative data on defect height. To achieve quantitative evaluation, it is necessary to master the techniques of quantitative calculation of pipeline stress and weak ring analysis, as well as to develop and revise pipeline defect assessment procedures.

The Science and Technology Development Center of China Petroleum and Chemical Corporation has issued a key research project on the quantitative inspection and evaluation of pressure pipeline welds in response to the above issues. The project is jointly carried out by Anhui Huaxia High tech Development Co., Ltd., Zhengli Petrochemical Equipment Research Institute, Shanghai Refinery of Gaoqiao Petrochemical Branch, and Jiujiang Petrochemical Branch. After several years of efforts, the following main scientific research achievements have been achieved.

1. We have successfully developed a low-frequency modulation magnetic detector for pipelines. In response to the skin effect of AC magnetic fields and the inability of magnetic particle particles in DC magnetic fields to film, we have developed a DPM-1 low-frequency modulation magnetic detector for pipelines that can be used for both direct and alternating currents. After being powered on, it can detect the surface and internal defects of the entire weld seam of the pipeline within 2 seconds; Pipelines below 108mm can detect defects with burial depths of 5-8 mm, making detection convenient, fast, and intuitive.

2. Successfully developed a small cutting-edge tile shaped line focused ultrasonic sensor, mainly using the tile shaped line focusing method to overcome the scattering of sound beams from thin-walled tubes to improve detection sensitivity; Using a small front to detect defects in one wave scan; Enable the sensor to have narrow echo pulses to improve resolution, and control the initial wave width within 2.5 mm to accurately locate defects in 3.5 mm thin-walled tubes; Improve wedge design and material selection to reduce clutter and ensure sensor stability; Adopting new chip materials to improve detection sensitivity, increasing chip backing damping to increase focusing effect and resolution, etc., resulting in a 20dB increase in probe sensitivity; Not only can it achieve the detection of small diameter thin-walled pipes, but also achieve high accuracy up to± Within 0.5 mm, achieve the four fixed requirements of height, length, positioning, and quality in engineering applications.

3. The calculation of pipeline stress and weak ring analysis provide four major functions:

a. Provide various quantitative stress data for quantitative comprehensive evaluation.

b. Focusing on high stress and weak ring areas for spot checks, making the spot checks scientific and reasonable.

c. Provide suggestions for reasonable pipeline layout.

d. Provide a basis for pipeline failure analysis.

4. Revise the in-service pressure pipeline defect assessment code CPDA-2001. Based on our original CPDA-96, conduct pipeline blasting and stress testing with defects, and combine new research results and engineering trial experience to supplement four chapters of content: including quantitative assessment methods for high strain areas (tees and crosses) of pipelines; Quantitative calculation method for fatigue life; Quantitative assessment methods for stress corrosion and corrosion fatigue; Comprehensive evaluation methods considering various geometric defects and wall thickness reduction factors, etc