In this paper, stress analysis of the inner partition plate of large-diameter storage tank in a project was carried out by ANSYS. The stress and deformation of the S-shaped and flat partition plate were compared. The analysis results indicate that the flat partition plate with reinforcing bar is more reasonable. Compared with the S-shaped structure, the stress level of the tank wall under the deformation of the inner flat plate is smaller. Meanwhile, the existence of supporting can limit the deformation of the flat plate, thus reducing the stress of the partition plate and improving the bearing capacity, which may optimize the structure.

Combining with the actual production, this paper analyzed the imperfections of the inner roof deck used in the atmospheric product oil tanks which belong to the company. It made comparison between different types of inner roof decks from technical and economic aspects. Then it proposed the upgrading scheme of replacing aluminum roof deck+gas capsule sealing with roof deck being in full contact with the liquid surface+elastic compensation seal. With the implementation of the new scheme, the previous defects in roof deck and sealing used in the product oil tanks were effectively eliminated. In addition, the oil and gas leakage was reduced and the problem of excessive VOCs emission from the tanks was solved. Tank shutdown and maintenance frequency decreased and the safety of oil tanks has been improved. As a result, economic loss was retrieved and the expected effects were achieved. Thus, the study has verified the effectiveness of the upgrading scheme of roof deck being in full contact with the liquid surface+elastic compensation seal for atmospheric internal floating roof tanks.

Heat exchanger is a kind of highly important equipment in chemical field. It has been widely used in chemical, petroleum, food and other industries. In this paper, fluent 17.0 software is used to numerically simulate the heat exchanger performance at different baffle-plate spacing. The results show that, within the range of 100 to 300 mm baffle-plate spacing, the "flow dead zone" area increases and the pressure drop decreases with the increase of baffle-plate spacing; and the convection heat transfer coefficient presents a downward trend, while the convection heat transfer coefficient per unit pressure drop, the convection heat transfer coefficient per unit pump power, and JF factor increase gradually. The conclusions of the above study can provide a basis for the trends in the actual engineering of heat exchangers.

High pressure ammonia pump is an important imported rotating equipment for urea production unit of one company. In order to save production cost, it was decided to have the mechanical seal of the pump domestically manufactured. During the process of domestication of the spare parts, leakage occurred soon after the operation of the mechanical seal of the pump. The leakage of the mechanical seal will not only bring hidden danger to the stable operation of the production unit, but also pollute the environment. In serious cases, it can even cause accidents with injuries and deaths. Therefore, during an overhaul, a detailed analysis on the disassembled mechanical seal and the site conditions was carried out to find out the causes of the leakage and the corresponding treatment measures were proposed. The above analysis and treatment measures can provide reference for the treatment of equipment with similar faults.

It is usually difficult to carry out tank opening inspection for atmospheric storage tanks when they reach the maintenance cycle. On-line detection technology has become an effective means for the general survey of corrosion status of storage tanks because of its advantages such as no need for tank opening, back-flow and tank cleaning. As an important reserve tool commonly used in petroleum and petrochemical industries, serious accidents may occur once atmospheric storage tanks leak or fail due to corrosion. Therefore, it is particularly important to use online detection technology to regularly monitor the corrosion state of storage tanks. This paper introduces in detail two emerging on-line detection technologies including electromagnetic ultrasonic wall climbing detection and alternating current field measurement from such aspects as the detection principles, adaptabilities, the advantages and disadvantages. Comparative analysis with the previous detection technologies indicate that the application of new on-line detection technology has positive significance for maximizing the protection of tank safety, as well as providing data and methods for the safety evaluation of storage tanks.

Aiming at the cracking of the elbow weld junction at the inlet of the pipeline and the overstress on the inlet of flue gas turbine of heavy oil catalytic unit during the preheating process, theoretical calculation and practical monitoring of the thermal expansion displacement of the high-temperature heating pipeline at the flue gas turbine inlet are carried out to explore the quantitative monitoring method for the pipeline thermal displacement. By comparing the actual monitoring data with the theoretical value of calculated thermal displacement, it was analyzed that the jam fault in the horizontal pipe expansion at the inlet of flue gas turbine and the excessive thermal expansion of the vertical pipe were the main reasons for the cracking of the pipe weld and the overstressing at the inlet of flue gas turbine. According to the above reasons, scientific and reasonable piping replacement process and swing support improvement measures were developed so that the problem of the flue gas inlet piping was solved and the hidden danger in production was eliminated. The solution to this problem can provide reference for the operation monitoring and replacement of pipes and the improvement of swing support in similar devices.

In order to explore the creep fracture mechanism of P12 heat-resistant steel, a series of creep tests were carried out on P12 heat-resistant steel under 630 ℃ and 70 MPa stress conditions. Then the creeped specimens were examined by metallographic microscopy and analyzed by scanning electron microscopy to obtain the microstructure evolution during high temperature creep. And the level of carbide precipitation and pearlite spheroidization of P12 heat-resistant steel under creep was quantitatively analyzed by combining computer image processing technology. The results show that the prolongation of creep time increases the precipitation of carbides in P12 heat-resistant steel. On the one hand, the amount of carbides increases continuously, on the other hand, the size of carbides increases accordingly. The level of pearlite spheroidization also increases with the accumulation of creep time. When the creep time is 360 hours, the level of pearlite spheroidization is up to grade 3. In addition, the amount and size of cement carbon in the pearlite structure decreases sharply with the increase of creep time. The deterioration of the microstructure of P12 heat-resistant steel during creep may be an important factor for its creep fracture. In order to predict the service life of P12 high-temperature steam pipe, a series of high-temperature endurance tests were carried out to determine the relationship between Manson-Haferd parameter PMH(σ) and stressσ of P12 heat-resistant steel. Then Based on the Manson-Haferd parameter method, the service life of P12 high-temperature steam pipe with stress σ of 43.15 MPa and service temperature of 520 ℃ is predicted to be 199.8 thousand hours.

This paper introduces the manufacturing device and forming process for U-shaped medium-frequency induction hot bending of Cr25Ni35Nb+MA centrifugally cast steel pipe. By analyzing the material properties of centrifugally cast steel pipe, the reasonable heat treatment process before bending, propulsion rate, heating temperature and cooling mode are selected. Meanwhile, the paper analyzes the change rule of wall thickness reduction rate, ovality and flatness after the forming of U-shaped pipe. The quality of the formed product is checked by penetration test, microstructure observation, pigging test and hydraulic test. The test results indicate that the heat treatment before bending can reduce the bending cracks; qualified bent pipe can be obtained by selecting the process with propulsion rate of 30~50 mm/s, heating temperature of 850~950 ℃ and strong air cooling.

In order to solve the problem concerning the lack of design methods for the external supply of secondary high-pressure steam to supercritical thermal power units, this paper studies the design methods for low-capacity supercritical high back-pressure steam turbines. Thermodynamic calculation and structural design methods for small-capacity supercritical high-multiplier-pressure turbines have been developed on the basis of supercritical steam parameters, back-pressures and flow ranges. The turbine designed with this method has a back pressure of 4.0 MPa, a power rating of 25 MW, and a steam capacity of 241 t/h. The nozzle meridian shrinkage profile was used in the flow structure, which effectively solved the problem of big loss caused by short blades. Meanwhile, the turbine adopted a barrel-type cylinder structure, which effectively enhances the response speed of turbine starting and stopping. In addition, the design method solved the problem of assembling the barrel-type cylinder turbine, which can check the feasibility of the turbine design quickly.

Cold forming of metallic materials may result in work hardening which may affect the material properties. By comparing the cold forming methods and deformation rate limitations of pressure components in common international and domestic standards, this paper analyzes the similarities and differences of the relevant provisions in different standards. It also discusses the major control factors leading to the change of material properties during cold forming, the necessity of restoring material properties, and the heat treatment modes for restoring material properties. It is expected to enhance the understanding of technical personnel in this area so that they can apply such knowledge properly so as to ensure the operational performance of pressure component materials to meet engineering needs.

Decline of steam and boiler feed water quality can cause scaling of the compressor turbine in ethylene plant, which in turn can lead to the decrease of compressor working efficiency and significant increase of steam consumption. This paper analyzes the specific reasons of compressor turbine scaling in three sets of ethylene plants, and introduces in detail the treatment methods and precautions taken for shutdown immersion cleaning, filling detergent online cleaning, saturated steam online cleaning and so forth. Meanwhile, it proposes the countermeasures to prevent compressor turbine scaling, which can provide reference for the handling of similar problems.

As the service life of the storage tank increases, the amount of oil sludge at the bottom of the tank continues to increase. In order to avoid environmental pollution and resource waste caused by the presence of oil sludge and to ensure the long-term safe and stable operation of the tank, regular cleaning is necessary. The safe, efficient, and eco-friendly cleaning methods of regular cleaning are also increasingly valued by enterprises. This paper aims to summarize the current status and technical difficulties of existing cleaning technologies and provide suggestions for the development of efficient and intelligent tank cleaning technologies in the future. By comparing the current status of existing technologies such as mechanical tank cleaning technology and intelligent tank cleaning robot technology, the paper makes a comprehensive analysis of the existing technologies, and briefly describes the key technologies and technical difficulties in the process of intelligent development of tank cleaning technology from the aspects of hardware ontology structure and software application development. Through the above comparative analysis, it is finally concluded that the key to the development of intelligent cleaning technology is the safe explosion-proof technology, wireless power transfer technology, navigation and positioning intelligent algorithm, comprehensive positioning method of multi technology means and multi-sensors, and positioning and navigation technology based on robot vision in oil and gas space.