Thread Content
In the process of modern social development, various sectors of society have put forward high demands regarding the structural safety, reliability, and quality of petroleum machinery and equipment. Stable petroleum machinery and equipment can not only further improve the efficiency of oil extraction but also facilitate the smooth progress of subsequent work. To ensure that petroleum machinery and equipment remain in a relatively stable operating condition, comprehensive inspections must be carried out on them. As a testing method with high sensitivity that does not damage the original equipment, non-destructive testing technology is widely used in the inspection of petroleum machinery and equipment. Based on a thorough consideration of actual conditions, non-destructive testing techniques for petroleum machinery are explored to ensure that such machinery can perform its functions more effectively. 1 The Importance of Applying Non-Destructive Testing Technologies in Petroleum Machinery and Equipment 1.1 Characteristics and Development of Non-Destructive Testing Technologies 1.1.1 Characteristics of Non-Destructive Testing Technologies In practical applications, non-destructive testing technologies do not impose strict requirements on the surface smoothness of test specimens. They are easy to operate and highly sensitive in detecting defects, thus effectively meeting the petroleum industry’s needs for non-destructive testing of pressure vessels and pipelines. 1.1.2 Development of non-destructive testing techniques At present, non-destructive testing techniques have gone through stages such as non-destructive flaw detection and non-destructive evaluation. During the non-destructive testing phase, its main purpose is to detect various types of internal defects. During the subsequent non-destructive testing, it is necessary to examine the basic properties, structure, and condition of the test specimen. During the non-destructive evaluation phase, it is necessary not only to detect the aforementioned aspects but also to obtain more accurate information about the test specimen, such as its shape, position, and dimensions. 1.2 The Importance of Non-Destructive Testing Technologies: With the development of society, modern industry has achieved comprehensive growth. There is a growing emphasis on inspection technologies for oil and gas machinery, in order to ensure that such equipment operates in a normal and stable manner. This not only facilitates the subsequent safe production of oil companies, but also brings them better social and economic benefits. Due to the significant particularities of petroleum machinery and equipment, the effectiveness of various conventional testing methods is relatively poor. To ensure the stable operation of petroleum machinery and equipment, efficient inspection methods—non-destructive testing—are necessary. Currently, as China places increasing emphasis on the application of non-destructive testing techniques in petroleum machinery and equipment, higher demands are being placed on the use of such techniques. Non-destructive testing techniques are widely used in petroleum machinery and equipment, such as in pressure vessels and transportation pipelines within the petrochemical industry. Since there are flammable gases or liquids inside these containers, and the internal pressure is at a high level, relying on simple conventional inspection methods can easily lead to various accidents, causing significant economic losses for the enterprise. In such cases, applying non-destructive testing techniques can not only effectively solve the problems but also facilitate the normal production and development of the enterprise in the future. 2 Current Status of the Application of Non-Destructive Testing Techniques in Petroleum Machinery and Equipment 2.1 Low Comprehensive Qualities of Inspectors Although the workforce involved in non-destructive testing of petroleum machinery and equipment is continuously improving, with an increasing number of inspectors overall, the demands regarding their comprehensive skills are also rising as the socio-economic level improves. Some personnel fail to meet the relevant requirements of enterprises in terms of professional competence; they can only perform relatively simple tasks. In the course of their daily work, they rely solely on their own experience, which may have a negative impact on the practical application of petroleum machinery and equipment. Most of the personnel involved in non-destructive testing for petroleum machinery and equipment have not received standardized professional training; their work capabilities and technical skills remain at a relatively basic level, and there is a lack of specialized researchers within the industry who are tasked with conducting research in this field. Relevant surveys show that China’s current non-destructive testing personnel need further improvement in terms of personal qualities and professional competence. Only by doing so can the proper application of non-destructive testing techniques for petrochemical equipment be ensured, thereby improving the accuracy of test results and helping petrochemical companies achieve better economic and social benefits. 2.2 Current status of the development of inspection personnel In the actual process of performing non-destructive testing on various petroleum machinery and equipment, there are some relatively significant issues within this field. With the overall gradual improvement in the level of social sciences, the chemical industry has achieved comprehensive development and innovation. The application of various advanced technologies in the chemical industry has played a positive role in promoting the stable development of the entire industry. From the perspective of non-destructive testing techniques for petroleum machinery and equipment, various advanced scientific and technological methods play a crucial role in the actual inspection process of such equipment. Against the backdrop of economic globalization, China is placing increasing emphasis on inspection technologies for petroleum machinery and equipment, and its team of professionals in non-destructive testing of such equipment is also growing continuously. However, due to the limitations in our country’s development, there has been no sustained growth in the number of non-destructive testing personnel, which has adversely affected the efficiency of non-destructive testing for petroleum machinery and equipment. In short, at present, the professional development of personnel engaged in non-destructive testing of petroleum machinery and equipment is restricted, with a relatively slow pace of progress, which hinders the smooth advancement of such testing activities in the future. 3 Specific application measures of non-destructive testing techniques in petroleum machinery and equipment. In petrochemical production, petroleum machinery and equipment play a crucial role. However, petroleum machinery and equipment lack universal testing devices, making it impossible to conduct general assessments of the degree of damage to such equipment. This requires the use of specialized testing techniques for petroleum machinery and equipment to ensure that various subsequent petrochemical operations can be carried out properly. Based on the non-destructive testing techniques for petroleum machinery and equipment, and taking into account the current status of such testing efforts in the past, the application of these techniques is optimized to ensure that they achieve the desired results. 3.1 Ultrasonic testing technology: In the inspection of petroleum machinery and equipment, ultrasonic testing technology is widely used to detect defects such as welds, pores, and cracks in these devices, offering high reliability and accuracy. Ultrasonic testing technology utilizes frequencies ranging from 0.1 to 5.0 MHz. Specialized signal processing software is used to generate narrow single-pulse signals, which are then transmitted to petroleum machinery and equipment via cables and computer interfaces. These signals propagate through elastic media through ultrasonic vibrations; when they encounter interfaces, they are reflected, and this phenomenon is used to determine the specific types of damage present in the petroleum machinery and equipment, such as the width and location of cracks. In conducting ultrasonic testing on petroleum detection equipment, the signal transmitting and receiving transducers should be fixed along the same straight line to form a highly integrated transducer array. Thereafter, the A-scan method can be used to detect various hidden defects within the mechanical equipment. The oscilloscope for petroleum machinery equipment, which uses computer-based devices for data collection, can efficiently transmit and reflect signal data, thereby providing information such as the width and exact location of cracks within the internal structure of the petroleum machinery equipment. 3.2 Magnetic Particle Inspection Method The magnetic particle inspection method is mostly used in high-quality, large-scale petroleum machinery and equipment that are difficult to turn over, and it can detect defects such as stress cracks and delaminations. By analyzing the distribution patterns of defects in various types of petroleum machinery and equipment in actual use, it can be seen that the use of wet fluorescence display and yoke magnetism testing methods enables comprehensive inspection of areas such as the thickened sections, heat-affected zones, and welds of the equipment. It is also possible to detect transverse defects on the surface; when the depth of these surface defects exceeds about 5% of the equipment’s wall thickness, grinding is used to remove them. Currently, the medium used in magnetic particle inspection is mainly ferromagnetic particles coated with fluorescent material. These ferromagnetic particles are capable of generating corresponding magnetic induction lines after magnetization; if there are defects on the surface of petroleum machinery, the surface of such equipment will form a 90° angle with these magnetic induction lines. Magnetic induction lines can also continuously overflow at the defect sites, thereby forming a relatively complete leakage magnetic field. The leakage magnetic field can attract magnetic particles around petroleum machinery, resulting in clearer defect traces. To ensure the accuracy of magnetic particle testing, the relevant testers should regularly inspect the magnetizing equipment equipped with ammeters, and verify the precision of these instruments in accordance with relevant standard requirements, so as to guarantee accurate readings from the magnetizing equipment. 3.3 Penetrant Inspection Methods Penetrant inspection technology is widely used for detecting surface defects in petroleum machinery and equipment, such as welding cracks and fatigue cracks that can affect the service life of the equipment and the safety of pressure vessels; it offers excellent visibility as well as higher sensitivity. Before formal testing, petroleum machinery and equipment should first be cleaned with acetone-based cleaners to ensure that there are no contaminants such as rust or grease on their surfaces. After cleaning, wait for about 10 minutes to ensure that the surface of the petroleum machinery is dry. Nozzles are placed at a distance of about 30 mm from the surface of the petroleum machinery equipment, to allow for the proper penetration of a mixture of anhydrous alcohol and propanol in equal proportions. At the same time, it is necessary to stir the imaging agent well and apply it evenly to the petroleum machinery equipment; thereafter, a white light is used to illuminate the surface of the equipment in order to determine whether any defects such as longitudinal cracks exist in the root welding area. After the subsequent inspections are completed, a cleaning agent should be used to wipe away the developer remaining on the surface of the petroleum machinery and equipment, so as to handle such equipment efficiently in line with relevant requirements. 3.4 Radiation Inspection Method The radiation inspection technique is primarily used for the rapid detection of faults in petroleum machinery and equipment; it enables the determination, within a short time frame, of the specific residence time of materials in the reaction units as well as the solid material level. Currently, the most widely used radiographic inspection techniques are gamma rays and neutron backscattering measurement techniques; the main characteristic of gamma rays is that their intensity decreases gradually following an exponential pattern. By placing the gamma-ray device and detector at both ends of the petroleum machinery, a more accurate density distribution map of the operating medium inside the equipment can be obtained. By analyzing the spectral patterns, it is possible to more accurately identify issues such as leaks and packing defects within petroleum machinery and equipment. By determining the root causes of these problems, a foundation can be laid for improving and optimizing subsequent corrective measures. Neutron backscattering measurement technology features the gradual transformation of seed radiation into a chronic medium; it can act directly on the walls of petroleum machinery, absorbing the heat generated by those components, and then, in combination with level measurements, it helps to determine the boundaries between gases, solids, and liquids, thereby identifying serious issues such as hidden blockages within the equipment. Typically, the neutron source used in neutron backscattering measurement techniques is 241Am-Be. Neutrons are emitted using a neutron source and sent into the interfaces of petroleum machinery. By leveraging the activity of the neutron source, the interface pressure and wall thickness of the equipment can be analyzed, allowing for the accurate identification of various issues present within the equipment as well as the causes of those issues. 3.5 Eddy current testing method: Eddy current testing technology is widely used in the process of assessing defects in petroleum machinery, and it features high inspection efficiency and fast testing speeds. Electromagnetic induction forms the basis of eddy current testing technology. High-frequency alternating current can be used to flow through the probe’s excitation coil, thereby inducing eddy currents in the pipe column under inspection. By taking into account the impedance resulting from the influence of geometric defects on these eddy currents, it is possible to identify defects in petroleum machinery equipment. In the actual process of inspecting petroleum machinery and equipment, professional multi-frequency eddy current detectors can be used; such detectors operate at frequencies ranging from 100 to 1×106 Hz to conduct a thorough inspection of the petroleum equipment. Graphs representing the defect signals are obtained in the impedance plane, allowing it to be determined the direction of the waveforms associated with these defects. Phase analysis techniques are employed to distinguish between defect signals and interference signals, thereby yielding more accurate results. 4 Conclusions At present, the commonly used non-destructive testing techniques for petroleum machinery and equipment mainly include ultrasonic testing, magnetic particle testing, and radiographic testing. Different detection technologies differ in their technical principles, which results in varying detection outcomes. In the actual process of inspecting petroleum machinery and equipment, workers need to fully consider the basic inspection requirements of such equipment, employ appropriate non-destructive testing techniques, and carry out proper maintenance and management of these machines.