Rolling Conditions Research Articles

A novel intelligent control approach for lateral deviation in hot-rolled strip steel

This study presents an advanced intelligent control method that integrates ABAQUS simulation with the Derivative Dynamic Time Warping (DDTW) algorithm to enhance lateral deviation control in hot-rolled steel strips. Tested on a 2250 mm seven-stand tandem mill, the method incorporates a simulation model developed to assess control effectiveness under varying rolling conditions, including steel grades, strip widths, and thicknesses. The DDTW algorithm was employed to track the strip's centerline and accurately correct tail-end deviations, achieving over 96% accuracy. By combining real-time deviation data with the simulation, control precision was significantly enhanced, reducing deviation at the finishing mill exit by 20% compared to manual methods. Additionally, operator intervention was reduced by over 80%, and incident rates dropped by more than 60%, improving both process stability and product quality. These findings demonstrate the method's potential to optimize production consistency and minimize operational risks.

ATKB-PID: an adaptive control method for micro tension under complex hot rolling conditions

At present, the parameters of the controllers in hot rolling roughing microtension control systems are not adaptively adjustable to variations in working conditions, which compromises both width accuracy and production stability. To address this issue, this paper introduces an ATKB-PID adaptive micro tension control method. This method incorporates a linear attention layer and utilizes a K-Nearest Neighbors (KNN) algorithm to predict the optimal learning rate and inertia coefficient under actual operating conditions. Furthermore, an objective function is tailored to production indices to enhance model performance. Comparative experiments with both established and recently introduced controllers demonstrate that the proposed ATKB-PID method exhibits a smaller steady-state error and quicker adjustment time. The ATKB-PID control method is well-suited for the complex and dynamic microtension control demands in thermal roughing processes, showing promising application potential.

Modelling and industrial experiment on the dynamic deviation of rolling force during high precision rolling process

The dynamic deviation of rolling force during the rolling process is influenced by various coupling factors, including mill stiffness on the operating and driving sides, initial strip specifications, and roll crossing. These factors frequently lead to sickle bending of the strip and bearing wear. Although this dynamic deviation is crucial in the rolling process, the existing literature falls short in studying the mechanism of this deviation, both theoretically and experimentally. As a result, operators in industrial plants predominantly rely on experience to assess it and are unable to formulate specific adjustment plans. In this work, physical and mathematical models of rolling force deviation are developed to elucidate the underlying formation mechanism, taking into account the contact deformation of the roll system, plastic deformation of the strip and roll crossing models. Analysis of production data reveals that the dynamic deviation of rolling force exhibits three distinct fluctuation patterns: positive deviation, negative deviation, and alternating positive and negative deviation. Numerical simulations and industrial experiments are conducted to investigate the influencing factors and evolution rules of rolling force deviation under various rolling conditions. The results indicate that dynamic deviation increases with the growth of centreline deviation and wedge amount of strip, and exhibits a complex fluctuation pattern as the crossover angle increases. This is confirmed by both numerical simulations and experimental results. Based on these analytical results, several improvement methods have been implemented in industrial plants to reduce the dynamic deviation of rolling force. These include reducing stiffness deviation on both sides of the mill, narrowing the bearing housing clearance, and ensuring mill symmetry.

Texture evolution and anisotropy of TA18 titanium alloy strip under rolling and heat treatment conditions

Texture evolution and anisotropy of TA18 titanium alloy strip under rolling and heat treatment conditions

Rolling contact fatigue of ion nitrided and TiN coated AISI 4140 steel under pure rolling condition

Rolling contact fatigue of ion nitrided and TiN coated AISI 4140 steel under pure rolling condition

A Digital Twin-Based Study of Material Behavior in the Rolling Process

The study proposes the development of a digital twin model for the rolling process. This virtual representation allows for the investigation of how various rolling parameters influence the quality of the final product. By employing finite element analysis (FEA), the model can simulate the rolling process under different conditions. Specifically, the study focuses only workpiece material which includes aluminum alloy (Al2024) for digital twin scenario. Through simulations, critical parameters like the Z-force exerted on the workpiece can be determined and compared. This enables researchers to evaluate different scenarios and identify optimal rolling conditions without the need for costly physical experiments.

Influence of chemical composition of steels for production of grinding balls on their deformation characteristics

The conducted studies determined the patterns of influence of chemical composition and deformation parameters of ball steels with experimental chemical composition on their deformability. The development of experimental chemical compositions of ball steels was carried out based on the existing experience of domestic and foreign researchers, taking into account the possibility of further application of the obtained results for ball steels of standard grades. The studies were carried out using a specialized laboratory installation by the method of hot-rolling samples. An increase in the carbon content in the range of 0.72 ‒ 0.85 %, manganese in the range from 0.72 to 0.85 %, chromium in the range of 0.38 – 1.71 % and nickel in the range from 0.08 to 0.87 % has a significant effect on increasing the deformation resistance of steels. At the same time, the quantitative effect of carbon content in the steels on their deformation resistance is much more pronounced in relation to manganese, chromium and nickel. It was determined that a decrease in the deformation temperature from 1200 to 900 °C, an increase in the deformation rate in the range from 1 to 10 s–1 and true deformation in the range 0.05 ‒ 0.35 cause an increase in the deformation resistance of ball steels, regardless of their chemical composition. The influence of all these parameters on the deformation resistance of steels has a pronounced nonlinear character and the deformation temperature has the greatest relative influence on the deformation resistance. The data obtained are summarized in the form of a multiple regression equation, which establishes the quantitative relationship between the resistance of steel to deformation with its chemical composition and deformation para­meters. Verification of the adequacy of the obtained equation in relation to the rolling conditions of ball steel billets of standard grades at the continuous medium-grade mill 450 of JSC EVRAZ United West Siberian Metallurgical Plant confirmed the possibility of using it to predict the energy-power parameters of rolling ball steels of various chemical composition.

Исследование распределения нормальных контактных напряжений в очагах деформации при горячей прокатке полос из конструкционных низколегированных сталей для повышения стойкости рабочих валков

Introduction. During the operation of the working rolls of the finishing groups of continuous wide-strip hot rolling mills, normal contact stresses have a decisive influence on its resistance and strength, especially when rolling a range of low-alloy structural steels with a minimum thickness range of 5.5–2.0 mm, which does not correspond to the passport characteristics of such mills. The subject of the study. Previously performed studies of the stress-strain state of the rolled strip in the deformation zones make it possible to estimate the level of normal contact stresses acting on the working rolls during hot rolling of strips of low-carbon steels. The paper discusses the results of the study of the stressed state of strips of low-alloy structural steels in contact with rolls, taking into account the features of the chemical composition of the metal and changes in its elastic properties during deformation at hot rolling temperatures. The results obtained are applicable to the evaluation of the contact strength of the finishing rolls of the rolling mill. The purpose of the work is to investigate the distribution of normal contact stresses in the deformation zones during hot rolling of strips of low-alloy structural steels to ensure high resistance of the working rolls. Material and methods. The study is based on the elastic-plastic model and equations for calculating normal contact stresses for each section of the deformation zone. The specificity of variation of Young's modulus (modulus of elasticity) of low-alloyed structural steels in accordance with certain hot rolling temperatures is studied in detail, and the contact strength of high-chromium cast iron work rolls is evaluated. Results and discussion. A reliable regression equation is obtained for determining the values of the Young’s modulus of the rolled strip as a function of changing hot rolling temperatures. The results of a numerical experiment are presented in the form of calculating the maximum normal contact stresses using the elastic-plastic model of the deformation zone and assessing the contact strength of the work rolls based on actual rolling conditions on an operating mill. New improved technological modes of hot rolling of low-alloy structural steels (0.1 C-Cr-Si-Ni-Cu, 0.18 C-Cr-Mn-Ti and 0.14 C-2 Mn-N-V) are proposed, which make it possible to reduce the maximum contact stresses and increase the resistance of the working rolls.

Research of assessing the reliability of containers securing taking into account the actual metacentric height of the container ship

The study focuses on the impact of the metacentric height of container ships on the reliability of container securing systems in order to prevent container loss overboard, which is a significant issue in the shipping industry. It is noted that the increase in ship capacity is achieved by increasing the number of layers of containers stacked on deck. Dynamic loads on the securing means of containers stowed in the upper tiers of container stacks are increasing, that can be particularly dangerous in the intense rolling conditions. It is noted that the international shipping community is well aware of the significance of this issue and is working to develop solutions. Assessment of the expected reliability of securing systems and prevent container loss through a comprehensive analysis of relevant factors is considered. The complexity of this assessment lies in the presence of many uncertainties in the calculation algorithm. These uncertainties are supposed to be quantified taking into account the accumulated experience and statistical data within the framework of the TopTier industry project. Existing methods and calculation algorithms do not take into account the fact that the actual height of the center of gravity of containers differs from the accepted value. The goal of this article is to study the effect of the actual metacentric height of a container ship on the parameters of rolling and the loads on containers and their securing means depending on it. To do this, using the example of a real ultra large container ship, a comparative analysis of the effect of metacentric height on the rolling acceleration was performed. The effect of the rolling acceleration on the loads acting on the deck container stack has been shown. The necessity to take into account the actual height of the center of gravity of containers is justified for the correct determination the metacentric height of the container ship and calculation loads in order to ensure the safety of operation of container ships and prevent containers from being lost overboard.

Real-Time Load Monitoring System for Tuna Fishing Ships: A Solution to Combat Illegal Transshipment

Abstract Illegal fishing activities are the biggest challenge for Indonesia in protecting its territorial waters from illegal fish transhipment. To address this issue, a real-time load measurement system is needed on ships. Real-time measurement devices can also replace land-based measurement functions, thus improving the quality of catch during the transfer of tuna from the ship to the cold storage. The method used in this research is testing, which requires real data to support and simulate the implementation of the study. The research involves a prototype that utilizes a load cell as a sensor for detecting the mass of fish, and NodeMCU as a microcontroller programmed with Arduino IDE language. The prototype is integrated with Wi-Fi to send data to a MySQL database. The sensor circuit consists of four load cells, a junction box, and an HX711 amplifier. The results of the sensor experiment at a 12-degree tilt condition, which indicates the roll or trim condition of the ship, show a decrease in sensor accuracy and relatively unstable results compared to normal conditions. The average accuracy rate of sensor readings under normal conditions is 99.42%, while the average accuracy rate of sensor readings at a 12-degree tilt is 96.98%.

Thermo-hydraulic performance of SCO2 in PCHE with NACA 4822 asymmetric airfoil fins under ocean rolling conditions

To enhance the heat transfer efficiency of a printed circuit heat exchanger (PCHE) under ocean rolling conditions, a fractal structure of the NACA 4822 asymmetric airfoil fins was proposed innovatively. This new configuration features two layers of channels: the upper is dedicated to hot CO2 while the lower is aimed for cold CO2. Notably, the asymmetric airfoil fin structure exhibits a remarkable improvement factor of heat transfer ranging from 1.0 to 3.5, accompanied by a friction factor ratio varying between 0.6 and 1.3, which signifies a dual benefit of reduced pressure drop and augmented heat transfer. Under rigorous analysis of the fractal-structured asymmetric airfoil fins in the PCHE, their performance is evaluated through varying rolling periods and angles. Our findings reveal that a rolling period of 2.0 s outperforms a rolling period of 4.0 s in terms of heat transfer performance. Specifically, at a rolling angle of 30°, the thermal performance soars by approximately 2.0 to 4.7 times, which indicates a positive correlation between a larger rolling angle and enhanced heat transfer. Intriguingly, the influence of the rolling angle on heat transfer performance eclipses that of the rolling period.

Assessing the impact of geometrical and geodetic parameters of equipment on technological conditions of cold rolling on a multi-stand mill

Assessing the impact of geometrical and geodetic parameters of equipment on technological conditions of cold rolling on a multi-stand mill

Functional properties of plastic deformation resistance of 12Kh18N10T steel

The resistance of metals and alloys to plastic deformation has functional properties, since it depends on the history of the development of deformation over time. This is especially true for hot deformation processes. At the same time, complexity of the mathematical description and lack of the necessary experimental equipment for a long time did not allow us to design functionals of this type. Currently, due to the emergence of multifunctional research complexes like Gleeble, such an opportunity has appeared. Accordingly, a methodology was developed to study the functional properties of the resistance of metals and alloys of plastic deformation, which was applied to the study of 12Kh18N10T steel. The choice of steel grade is due to the fact that the behavior of austenitic stainless steel during plastic deformation differs significantly from carbon steels. On the other hand, at present, more and more attention is being paid to the production of metal products from stainless steels. This is due, on the one hand, to the tighte­ning of the operating conditions of metal products, the development of new areas of their application and, on the other hand, a fairly high share of imports in the market of products made of austenitic stainless steels. Therefore, the study of the technological properties of such metals and alloys is relevant. At the same time, it should be noted that the most significant functional properties of the metal resistance to plastic deformation are manifested during hot deformation under continuous rolling conditions. Therefore, in this paper, the temperature range of hot plastic deformation is investigated. The results obtained can be used to determine the energy-power parameters in such processes as continuous rolling of strips in the finishing groups of strands and continuous rolling of sleeves in the lines of modern pipe rolling units.

Investigation of the kinematics of turning a wheeled vehicle with a variable track

BACKGROUND: The trapezoidal lever mechanism used in the steering drive for turning steerable wheels to change the direction of movement of a wheeled vehicle does not fully meet the conditions for observing rolling wheels without slipping and conforming to the correct kinematics of rotation, which is especially evident when adjusting the track. AIMS: assessment of the degree of discrepancy between the actual kinematics of the turn and the kinematics of the correct turn when changing the track of the tractor. MATERIALS AND METHODS: Analytical methods were used in the work, which made it possible to obtain some computational dependencies, perform a numerical analysis of the curvilinear motion of a tractor with a variable track for different parameters of the steering trapezoid, and on this basis establish patterns between the geometric characteristics of the steering trapezoid and the kinematic parameters. RESULTS: Rational geometric characteristics of the steering trapezoid, which make it possible to obtain the kinematic parameters of rotation closest to the required ones, are set for the most commonly used value of the width of the pivot track. For the Belarus-80.1 tractor, it corresponds to 1.02 m. At the same time, for example, at an angle of rotation of the inner steerable wheel of 25°, the minimum turning radius realized by the steering trapezoid is 0.6521 m (10.44%), and at 40° by 0.2829m (9.27%) differs from their values obtained from the pure rolling condition. When changing the track width of the machine, there is a violation of the initial geometric characteristics of the trapezoid and the corresponding mismatch of the kinematic parameters of the rotation carried out by the steering trapezoid and by the correct rotation increases. A comparison of the minimum turning radii at an angle of 25° and a pivot track of 1.42 m showed an increase of 3.2340 m (35.83%), and at 40° — by 0.8956 m (20.21%). CONCLUSION: To ensure the correct turn, it is necessary to conduct a thorough theoretical analysis of the never mechanism of the steering trapezoid and improve its design on this basis.

Effective strategies for improving quenched microstructure and mechanical properties of hot-rolled seamless steel pipes

The containing Ti-Mg-Ca-O composite particles were innovatively used to achieve microstructure refinement and properties improvement of hot-rolled seamless steel pipes, and compared with conventional steel (C# steel). The results show that the C# steel mainly consisted of parallel lath martensite after on-line quenching. Under the same rolling and heat treatment conditions, dominant Ti-Mg-Ca-O composite particles in modified steel (M# steel) were effective nucleation sites of acicular ferrite, dividing the prior austenite grains and refining microstructures. The strength values of the both steels were at the same level, however, the impact energy of M# steel was significantly higher than C# steel, increasing by 28%. This study provides an effective method for further microstructure refinement of hot-rolled seamless steel tubes.

Foam Rolling Intervention Improves Lactate Clearance After High-Intensity Exercise.

The acute effects of a foam rolling intervention on lactate clearance and the impaired executive function associated with fatigue after high-intensity exercise remain unclear. This study examined whether foam rolling is an effective tool for fatigue recovery. Eighteen healthy adults without consistent exercise habits participated in this study. Participants performed high-intensity exercises, and the post-exercise foam rolling intervention was compared to the control condition. Measurements included lactate, vigor/fatigue by the Profile of Mood States 2nd Edition, cognitive function (cognitive task performance), leg and body rating of perceived exertion pre- and post-exercise, and post-intervention. Blood lactate concentrations post-foam rolling intervention (-7.3 ± 3.0 mmol/L) were significantly reduced among all participants. Increased lactate clearance by foam rolling correlated with a faster recovery of executive function for those with greater lactate clearance. However, cognitive fatigue was not observed after high-intensity exercise (p = 0.086, r = 0.41). Lactate clearance was not significantly correlated with the rating of perceived exertion in the foam rolling condition. The rating of the perceived exertion decreased with increased lactate clearance for those with greater lactate clearance in the control condition (leg: r = 0.778; body: r = 0.669). In conclusion, foam rolling intervention may be effective for exhausting exercise recovery.

Effect of Rolling Process Parameters on Transverse Cracks on the Surface of Q345 Steel

This article examines the evolutionary behavior of transverse surface cracks in Q345 steel during the hot‐rolling process under various rolling conditions. “V”‐shaped cracks are prefabricated on the billet surface for laboratory hot‐rolling tests, and a corresponding rolling model is developed to validate its accuracy. The slab rolling model is established based on actual onsite rolling process parameters. The aim is to analyze the effects of different rolling conditions on the surface crack morphology and aspect ratio. The results indicate that variations in roll diameter (1400, 1300, and 1200 mm) influence crack propagation, with cracks unfolding earlier when the roll diameter is 1400 mm. At varying initial rolling temperatures (1300, 1200, and 1100 °C), cracks begin to unfold earlier at the highest temperature of 1300 °C. When examining different friction coefficients (0.4, 0.5, and 0.6), cracks unfold earlier at the highest coefficient of 0.6. Similarly, at different rolling speeds (3, 4, and 5 m s−1), cracks unfolded earlier at the highest speed of 5 m s−1. Analysis of changes in crack depth and aspect ratio during rolling shows that the initial few passes have a greater influence on crack depth and unfolding. In the later stages of rolling, cracks continue to unfold, though the depth shows minimal variation, and the aspect ratio tends to approach zero.

Research on dynamic swing experiment of atomic gravimeter based on the inertially stabilized platform

Abstract Based on the principle of quantum interference, with excellent accuracy, sensitivity, and stability, miniaturized and portable atomic gravimeters are gradually exploring the possibility of applying them to mobile platforms such as ships. However, the vibration noise brought by the dynamic environment has a great influence on it. To explore the stability and reliability of the atomic gravimeter in the mobile platform, we built a dynamic measurement system of the atomic gravimeter in the laboratory. With the help of the swing test bench, the swing of the roll and pitch directions was added to the system to simulate the wave environment, and the dynamic swing experiment was carried out. By changing different swing levels, the system can work in different vibration environments and measure the gravity value. The experimental results show that the atomic gravimeter can work normally in various swing environments, and the internal coincidence accuracy of 1.861 mGal is achieved. The measurement standard deviation of 2.194 mGal and the resolution of 1.160 mGal@48 s are obtained under static conditions. The measurement standard deviation of 34.200 mGal and the resolution of 9.538 mGal@48s are obtained under mixed swing conditions. Under the condition of mixed rolling, the standard deviation of the interference phase noise of the atomic gravimeter and its contribution to the resolution of gravity measurement reach 23.121 π mrad and 2.045×10−6 g/shot, respectively. Our work provides a new reference for the research of high-precision atomic gravimeters based on quantum sensing technology in the field of gravity measurement in ship-borne environments.

Mechanism of Wheel-Rail Adhesion Recovery During Large Sliding Processes Under Water Lubrication Condition

The challenge of low adhesion between the wheel and the rail constrains the advancement of train braking technologies, resulting in sliding during braking, increased braking distances, and even operational safety incidents. Low adhesion arises from the contamination of the rail surface by a third body, such as water or oil, significantly reducing adhesion. However, experimental studies have found that wheel-rail adhesion coefficient under water lubrication conditions possesses recovery capability. In scenarios characterized by low adhesion in water lubrication conditions, a secondary rise in adhesion occurs when substantial wheel-rail sliding is present. This paper focuses on numerically modeling the unique phenomenon of adhesion recovery during large-sliding processes under water lubrication conditions. Considering the notable differences in frictional heating during wheel sliding, as opposed to pure rolling conditions, we construct a wheel-rail contact model under mixed lubrication conditions that incorporates the solid–liquid coupled heat transfer effect. This model achieves stable solutions for the wheel-rail contact relationship and the temperature at the wheel-rail interface. The impacts of velocity, axle load, water temperature, and slide ratio on the adhesion recovery phenomenon are discussed, revealing the underlying mechanism of adhesion recovery during large sliding processes. Finally, brake adhesion tests under water lubrication conditions are conducted on a scaled test rig to validate the proposed theoretical model.

СОГЛАСОВАНИЕ ГЕОМЕТРИЧЕСКИХ ХАРАКТЕРИСТИК ФАКТИЧЕСКОГО ПОВОРОТА КОЛЁСНОЙ МАШИНЫ

Based on the above calculation scheme of controlled curvilinear motion of a wheeled vehicle, it was revealed that the steering trapezoid causes some discrepancy between the kinematics of real and correct rotation. It is established that when adjusting the track width of the machine, the kinematic mismatch between the optimal rolling conditions of the wheels increases, and, consequently, the calculated dependences of the parameters of the ideal turn will not give a satisfactory result when analyzing the actual turn. The minimum theoretical turning radius is taken as an estimated indicator of the turnability of a wheeled vehicle. The conclusion of a multifunctional analytical dependence for determining the theoretical minimum turning radius of a wheeled vehicle, the wheels of which are controlled by a steering trapezoid, is presented. The resulting formula includes the longitudinal base of the machine, the pin track, the angles of rotation of the inner and outer steerable wheels. A comparison of the calculation results according to the developed and known formulas is given, which confirmed the complete convergence. It was found that, for example, an increase in the pivot track of the machine by 0.2 m leads to an increase in the theoretical minimum radius of the actual turn by 16.5%, and the distance from the continuation of the rear axle to the instantaneous center of rotation by 45.07...98.02% when the angle of rotation of the inner steering wheel changes from 20° to 40°.