Diameter Steel Ball Research Articles

Forced convective rate and pressure drop through a packed annulus: a numerical simulation

Porous materials are used in engineering and industry due to their heat transmission qualities. This study examined forced convection flow through an annular tube packed with sphere balls of various materials and sizes using numerical analysis. The sphere balls were permeable. Ceramic, plastic, and steel with spherical diameters of 3, 5, and 6 and porosity of 0.4 were tested for heat dissipated and fluid flow. Also, test the impact of steel balls of diameter 6mm with 0.6 and 0.8 porosity. The numerical simulation results are used to analyze the forced convection and fluid flow parameters of a three-dimensional annular tube with continuous heat flux in the Reynold number range (5000-14000). Steel balls had an 80% higher heat transfer coefficient than annular tubes without porous mediums. The simulation showed that inserting the porous media increased annular tube pressure loss. The maximum heat transfer coefficient improved by about 80% when the spherical diameter is 3 mm. Also, the result illustrated the heat transfer coefficient of steel balls Increased by about 79%, 69%, and 49%, with 0.4, 0.6, and 0.8 respectively

A Cost-Effective Integrated Methodology for Electromagnetic Actuation via Visual Feedback.

Electromagnetic actuation can support many fields of technology, such as robotics or biomedical applications. In this context, fully understanding the system behavior and proposing a low-cost package for feedback control is challenging. Modeling the electromagnetic force is particularly tricky because it is a nonlinear function of the actuated object's position and coil's current. Measuring in real time the position of the actuated object with the precision required for accurate motion control is also nontrivial. In this study, we propose a novel, cost-effective electromagnetic set-up to achieve position control via visual feedback. We actuated vertically and under different experimental conditions a 10 mm diameter steel ball hanging on a low-stiffness spring, demonstrating good tracking performance (the position error remained within ±0.5 mm, with a negligible phase delay in the best scenarios). The experimental results confirm the feasibility of the proposed set-up, which is characterized by minimum complexity and realized with off-the-shelf and cost-effective components. For these reasons, such a contribution helps to understand and apply electromagnetic actuation even further.

An inclined pedal type piezoelectric energy harvester for pedestrian flow and vehicle safety monitoring

This paper proposed an inclined pedal-type piezoelectric energy harvester for pedestrian monitoring and vehicle safety monitoring (IPEH). The IPEH exterior adopts an inclined pedal design, the steel ball is placed inside its cylindrical channel to excite the piezoelectric patches to harvest and convert external mechanical energy. IPEH can be placed under the brake pedal of a car for the function of vehicle safety monitoring. IPEH can also be fixed on the road as an energy harvester and monitoring device, harvesting pedestrian trampling energy and monitoring the density of pedestrian traffic in realtime. The influence of the steel ball diameter and spring layout on the output performance of the prototype is studied in this paper. Under the best parameters of the prototype assembly, the maximum output voltage is 165.6 Vpp, and the maximum output power is 463.7 mW. In the application experiment, the practicability in energy harvesting applications of IPEH is verified through the experiment of lighting LEDs and charging capacity, and the monitoring ability of IPEH was verified by simulating the experiment of different human flow walking and vehicle braking. It provides a new idea for the subsequent application of piezoelectric equipment in traffic auxiliary facilities and intelligent sensing equipment.

Effect of Shot Peening on the Low-Cycle Fatigue Behavior of an AA2519-T62 Friction-Stir-Welded Butt Joint.

In this investigation, an AA2519-T62 FSW butt joint was subjected to shot peening with an air pressure of p = 0.6 MPa, a processing time of t = 10 min (per side), and a steel ball diameter of dk = 1.5 mm. In order to evaluate the impact of shot peening on the low-cycle behavior, the samples were tested with coefficient R = 0.1 at total strain amplitudes of 0.35%, 0.4%, and 0.5%. The shot-peened welds are characterized by a higher value of stress amplitude, a lower value of plastic strain amplitude, and their fatigue life increased slightly. The cyclic strength coefficient and the cyclic strain hardening exponent were reduced by 45% and 55%, respectively, as the result of the surface layer hardening. The shot peening process had no noticeable effect on the character of crack initiation and propagation. Almost in all cases, the cracking started in the area under the weld face, located close to the boundary between the thermo-mechanically affected zone and the stir zone at the advancing side. Only at the heaviest loadings (εac = 0.5%) were cracks initiated in the heat-affected zone at the retreating side. Despite the introduction of small cracks in the stir zone, their presence did not affect the decohesion character of the welded joint. Overall, it was observed that there is a minimal, positive impact of shot peening on the properties of the investigated joints.

A novel method for ball forming by cross wedge rolling

In this paper, a novel method for ball forming by cross wedge rolling (CWR) was proposed, and the finite element (FE) simulation and experimental verification were carried out with the 26 mm diameter steel ball as an example. First of all, the die parameters including spreading angle β and forming angle α were selected and the 3D models of the die and guide plate were designed. Then, the FE model was established and preliminary simulation was carried out using the Simufact 16.0 software. The preliminary simulation results showed that the pushing empty defect occurred in the process due to lack of transition from spreading stage to sizing stage and conical die section. Modifying the die design by adopting the method of adding transition spreading angle θ and forming angle α´ increasing with the increase of rolling depth to, the defect could be eliminated and the full filling can be obtained. In addition, the simulation analysis after modified also included effective strain and stress distribution, the kinematic analysis of metal flow, the damage distribution based on the Cockcroft-Latham criterion, the temperature evolution and force parameters in the CWR process. Finally, the rolling experiments and radial rolling force testing experiments were carried out to verify the numerical results. The results indicated that the FE simulation results were consistent with the experimental results through quantitative analysis, which proved that the novel method for ball forming by CWR was feasible simultaneously.

Energy efficiency analysis of a rotating-drum dryer using hot steel balls for converter sludge

We proposed a novel rotating-drum technology for drying converter sludge with high efficiency and low cost. This study aimed to investigate the drying energy efficiency of our technology and the effect of sludge treatment mass (ms0 = 3.0–9.0 kg), steel ball temperature (Tb0 = 300–500 °C), steel ball diameter (d = 20–40 mm), and drum rotating speed (n = 1–7 rpm). The evaluation criteria of energy efficiency included energy utilization rate (ηb), specific energy consumption (SEC), drying rate (DR), etc. Results showed that appropriately increasing ms0 and decreasing Tb0 can increase ηb and reduce SEC, but also reduced DR. Selecting appropriate d and n can not only increase ηb and DR, but also reduce SEC. Under our experimental conditions, ηb is 50–95%, SEC is 0.8–1.5 kW·h/kgw, and DR is 1.0 × 10−4–1.8 × 10−3 g/(g·s). The improved self-scaling method was used to evaluate the energy efficiency under the studied working conditions, and the comprehensive optimal combination of operating parameters was obtained in our experiments, which can be achieved ηb > 78%, SEC < 1.0 kW·h/kgw, and DR > 9.9 × 10−4 g/(g·s).

Analysis of failure characteristics and mechanical mechanisms of sandstone during spherical indenter intrusion based on acoustic emission experiment

This paper aims to investigate the effects of steel ball diameter on failure characteristics and mechanical mechanisms of sandstone during the spherical indenter intrusion process. By using equipment such as acoustic emission (AE), the process of spherical indenter intrusion into sandstone was monitored and recorded for analysis of the fracture characteristics, load-depth relationship, and specific energy of sandstone under spherical indenters with different diameters. The results showed that as the diameter of the spherical indenter increased, the peak load of the sandstone increased continuously, and the failure mode transitioned from “jump-type” to plastic, with the acoustic emission count exhibiting a staged variation characteristic. During this process, the accumulated acoustic emission count, intrusion coefficient, and specific energy of intrusion all exhibited a “parabolic” law of first decreasing and then increasing, all of which reached minimum values when the ratio of the diameter of indenter to sandstone was close to 1.0. This indicated that as the diameter of the indenter approaches that of the sandstone, the intrusion process becomes more facile and efficient. Finally, the study revealed the formation mechanism of dense core and crack inside the sandstone during intrusion, and discussed the law of the crushing rate in ball milling from the perspective of compression. The conclusions contribute to revealing the fragmentation mechanics of rocks in the ball milling process and aid in determining the ball loading parameters in the milling process based on rock properties, aiming to achieve energy-saving and cost reduction.

A method for sensitivity analysis of deviation factor for geometric correction of cone-beam CT system

To propose a sensitivity test method for geometric correction position deviation of cone-beam CT systems. We proposed the definition of center deviation and its derivation. We analyzed the influence of the variation of the three-dimensional spatial center of the steel ball point, the projection center and the size of the steel ball point on the deviation of geometric parameters and the reconstructed image results by calculating the geometric correction parameters based on the Noo analytical method using the FDK reconstruction algorithm for image reconstruction. The radius of the steel ball point was within 3 mm. The deviation of the center of the calibration parameter was within the order of magnitude and negligible. A 10% Gaussian perturbation of a single pixel in the 3D spatial coordinates of the steel ball point produced a deviation of about 3 pixel sizes, while the same Gaussian perturbation of the 2D projection coordinates of the steel ball point produced a deviation of about 2 pixel sizes. The geometric correction is more sensitive to the deviation generated by the three-dimensional spatial coordinates of the steel ball point with limited sensitivity to the deviation generated by the two-dimensional projection coordinates of the steel ball point. The deviation sensitivity of a small diameter steel ball point can be ignored.

Recovery of Carbon and Cryolite from Spent Carbon Anode Slag Using a Grinding Flotation Process Based on Mineralogical Characteristics

The aluminum electrolysis industry continually and unavoidably produces hazardous solid waste in the form of carbon anode slag. Carbon anode slag poses a serious environmental pollution risk, and it must be disposed of in a harmless manner. On the other hand, it contains a few valuable resources, as well. In order for the aluminum electrolysis industry to develop in an environmentally friendly and high-quality manner, the harmless disposal of carbon anode slag and its resourceful utilization are of considerable importance. The selective comminution of carbon and cryolite particles in carbon anode slag can be effectively achieved with grinding pretreatment. However, the optimization study of grinding process parameters has yet to be investigated. Therefore, firstly, the mineralogical characteristics and existing mode of carbon anode slag from the perspective of mineralogical properties are analyzed in this study. Then, the effects of grinding time, grinding concentration, and steel ball diameter on the particle size of the ground product (γ−0.074 mm) are investigated using response surface analysis. The results showed that the effect of grinding time was the most significant, followed by grinding concentration and steel ball diameter. In addition, the performance of the multi-stage flotation process for separating the −0.074 mm ground product was analyzed. Cryolite with a purity of 93.12% and a carbon product with an ash content of 10.67% could be simultaneously obtained through multi-stage flotation. It should be pointed out that the deep dissociation and efficient recovery of fine undissociated particles still need to be further explored.

Dynamic Features of Non-Return Mechanism in Hatch Door of Amphibious Aircraft

The non-return mechanism is the key device that plays the role of braking in the opening-and-closing electric actuator of an amphibious aircraft hatch door. The ball-and-socket contact pair, providing the pressing force, and the multi-disc friction pair, supplying the braking torque, are two core components in the non-return mechanism. In this paper, the dynamic model of the non-return mechanism is established considering the freedom of rotation-translation. Based on MATLAB/Simulink, the solution framework of the overall dynamic model is built. The dynamic response characteristics of the non-return mechanism in the process of reverse load braking, forward load braking, and continuous closing are analyzed. The braking time and the angular displacement of the output shaft in the braking phase have been presented. Compared with forward load braking, reverse load braking has a longer braking time and smaller angular displacement of the output shaft. In addition, the compaction function of the ball-and-socket contact pair is verified by experiment, and the influence of the cone angle, distribution radius of the ball socket, and the steel ball diameter on the pressing force has been discussed. This study provides a theoretical basis and parametric design platform for the design and optimization of non-return mechanisms, which can shorten the product development time.

Automatic measurement of beam-positioning accuracy at off-isocenter positions.

This study performed an automatic measurement of the off-axis beam-positioning accuracy at a single isocenter via the TrueBeam Developer mode and evaluated the beam-positioning accuracy considering the effect of couch rotational errors. TrueBeam STx and the Winston-Lutz test-dedicated phantom, with a 3 mm diameter steel ball, were used in this study. The phantom was placed on the treatment couch, and the Winston-Lutz test was performed at the isocenter for four gantry angles (0°, 90°, 180°, and 270°) using an electronic portal imaging device. The phantom offset positions were at distances of 0, 25, 50, 75, and 100mm from the isocenter along the superior-inferior, anterior-posterior, and left-right directions. Seventeen patterns of multileaf collimator-shaped square fields of 10 × 10 mm2 were created at the isocenter and off-axis positions for each gantry angle. The beam-positioning accuracy was evaluated with couch rotation along the yaw-axis (0°,±0.5°, and±1.0°). The mean beam-positioning errors at the isocenter and off-isocenter distances (from the isocenter to±100mm) were 0.46-0.60, 0.44-0.91, and 0.42-1.11mm for the couch angles of 0°,±0.5°, and±1°, respectively. The beam-positioning errors increased as the distance from the isocenter and couch rotation increased. These findings suggest that the beam-positioning accuracy at the isocenter and off-isocenter positions can be evaluated quickly and automatically using the TrueBeam Developer mode. The proposed procedure is expected to contribute to an efficient evaluation of the beam-positioning accuracy at off-isocenter positions.

Numerical simulation of ball milling reactor for novel ammonia synthesis under ambient conditions

The investigation models an alternative ammonia production method compared to the Haber-Bosch method. The operating parameters of proposed process, which successfully synthesized ammonia with competitive yield, were 45 °C and 1 bar, which is significantly lower than the Haber-Bosch process. A study was made on the impact and contact behavior of the planetary ball mill to understand the movement of steel balls and iron particles inside the reactor vessel to improve the synthesis process. The EDEM software, based on discrete element method (DEM), was used to understand the internal behavior of a planetary mill. Balls and particles were loaded at a ratio of 1:20, i.e., 500 g of steel ball diameter is 25 mm, and 24 g of iron particles diameter is 0.25 mm in reactor. Contact and energy released by balls and particles as a function of mill speed were compared with the experimental correlation of adsorbed nitrogen. The correlation with the experimental data showed satisfactory agreement with present numerical simulation. This work is the first step towards realistic scaling of the system and vertical mill is not a common practice on an industrial scale, this work will use experimental data to create and validate a vertical ball mill model.

Analysis of Lubricant Oil Characteristics Using the Ball Falling Relative Motion Method on Temperature Variations

The purpose of this research is to analyze the viscosity/viscosity of lubricating oil using the relative motion method of falling balls at various temperatures. This research is using experimental method. Where the test is carried out using temperature variations of 320C, 500C, 600C and 800C, steel balls with varying diameters, including 9.50 mm, 8.00 mm, 6.00 mm and 4.80 mm as well as variations in the viscosity of lubricating oil, including SAE. 10, SAE 40, SAE 90 and SAE 140. Data analysis used the method of calculating the fluid resistance equation of Stokes' law and the equation of motion from Newton's second law. The Stokes law equation by taking the example of a lubricant with a viscosity of SAE 10 is obtained for a steel ball diameter of 9.50 mm to obtain a fluid resistance of 7.159.200 m/s2, a steel ball with a diameter of 8.00 mm to obtain a fluid resistance of 6.028.800 m/s2, for a steel ball with a diameter of 6.00 mm obtained a fluid resistance of 4.521.600 m/s2, for a steel ball with a diameter of 4.80 mm, a fluid resistance of 3.617.280.000 m/s2 was obtained. It can be seen that at a certain viscosity value the weight of the steel ball will affect the fluid resistance, the greater the weight of the steel ball, the greater the fluid resistance value and vice versa. The equation of Newton's second law of motion shows that the lubricating oil with SAE 10 with 3.5 gram steel ball at a temperature of 32 is 17.92 gr.mm/s2, a temperature of 500C is 2471.8 gr.mm/s2, a temperature of 600C is 25396 ,82 gr.mm/s2, temperature 800C is 28000 gr.mm/s2. For the weight of the steel ball 2.1 grams at a temperature of 320C is 7609.98 gr.mm/s2, a temperature of 600C is 5555.5 gr.mm/s2, a temperature of 800C is 13884.15 gr.mm/s2. The results of the above calculations indicate that the viscosity value will decrease or decrease with increasing temperature applied to the lubricant, thus the flowability of the lubricating oil will increase faster.

Tribological performance of porous silicon hydrophobic and hydrophilic surfaces

Many studies have focused on surface texturing to control friction and wear in the past few decades. The underlying reasons for surface texturing effects under various contact situations remain a source of debate. The connection between surface roughness and friction between two sliding surfaces is more complicated than it looks at first glance. In this paper, samples of a highly resistive p-type silicon were anodized to get various pore sizes ranging from 0.01 up to 3.2 microns using two electrolyte solutions and varying the electric current. The wetting properties were determined via contact angle analysis, while pore size and shape measurements were performed by scanning electron microscopy. The tribological tests were performed on a tribometer (UMT, Bruker) in a reciprocating mode for 15 min with a 3N load, 5 Hz, and a 10 mm diameter steel ball. Wear surfaces were analyzed by optical microscopy and non-contact 3D profilometry. The results showed that low electric currents generate mesoporous silicon surfaces with low friction. Higher currents generate macroporous silicon surfaces, modifying the surface roughness and wetting properties from hydrophilic to hydrophobic and increasing friction. The pore size is directly related to the wear volume and scar diameter measured from optical micrographs and profilometry 3D. The larger the pore size and nanostructured peaks, the greater the contact angle, friction, and wear.

Corrosion Protection on AISI 304 by Shot Peening Treatment with Variation of Particle Size and Shooting Pressure

AISI 304 is widely used as biomedical material due to its lower cost and availability, but low corrosion resistance. The shot peening method can increase the mechanical characteristics and corrosion resistance of a surface. The purpose of this study was to determine the effect of shot peening surface treatment with a combination of steel ball diameter variations and pressure on corrosion resistance of AISI 304 material. Shot peening treatment was carried out using variations of 0.2, 0.5, and 0.8 mm steel ball diameters with a hardness of around 40-50 HRC. Shot peening pressure varies from 7, 8, and 9 bar. Corrosion rate testing was carried out using bovine serum media. The results showed that the best increase in corrosion resistance was 0.117 mpy for a steel ball diameter of 0.5 mm with a pressure of 9 bar, 3 times lower than that of non-treated specimens, which was 0.378 mpy.

Measurement of Steel Ball Diameter and Roundness Error Based on Fresnel Diffraction

Measurement of Steel Ball Diameter and Roundness Error Based on Fresnel Diffraction

Impact of soot nanoparticle size and quantity on four-ball steel wear characteristics using EDS, XRD and electron microscopy image analysis

The effect of soot contamination on the tribological performance of engine oil was investigated. Carbon black is introduced to simplify diesel engine soot contamination. Besides, the tribological performance issue is verified by a four-ball tribometer. The steel ball worn surfaces were studied by Scanning Electron Microscopy (SEM), Optical Microscope (OM) and Energy Dispersive X-ray spectroscopy (EDX). In addition, Transmission Electron Microscopy (TEM) was used to investigate the morphology and nanostructure of soot and carbon black. According to the four ball test results, the average wear scar diameter of steel ball tested with engine oil blended with N220, N330, N550 and N660 by 1% by weight is larger than that of pure engine oil by 26%, 38%, 41%, and 39%, respectively. The wear scar diameter tends to increase after blended larger size of carbon black particle. The steel balls tested with formulated engine oil without soot contamination and with soot contamination by 0.5 wt%, 1 wt%, and 2 wt% have average wear scar diameters of 621, 567, 784 and 894 nm, respectively. On the other hand, wear scar roughness of steel balls tested with formulated engine oil without soot contamination and with soot contamination by 0.5 wt%, 1 wt%, and 2 wt% were 2.28, 0.25, 1.49 and 1.76 μm, respectively.Consequently, quantity of the soot nanoparticle approximately 0.5% by mass in engine oil significantly plays an important role in steel ball wear scar diameter and surface roughness reduction. Moreover, the agglomerated soot which is larger than the oil film thickness might block the lubricant from entering the contact. It leads to the breakdown of the oil film thickness resulting in increasing adhesive wear on the worn surface.

The Effect of Grinding Media on Mineral Breakage Properties of Magnetite Ores

The breakage and liberation of minerals are the key to fluidized mining for minerals. In the ball milling process, steel balls function as not only a grinding action implementer but also energy carrier to determine the breakage behavior of ores and the production capacity of the mill. When ground products present a much coarse or much fine particle size distribution, the separation process will suffer, resulting in inefficient recovery of useful minerals. Optimal control of the particle size distribution of the products is therefore essential, but the complexity and randomness of ball mill grinding make it difficult to determine the appropriate ball size. To solve the problem in the precise measurement of grinding ball diameters, this paper carried out magnetite grinding experiments with grinding balls of different diameters under the same grinding conditions to study the influence pattern of steel ball diameters on the particle break behavior, the particle size distribution of ground products, and the mineral liberation degree distribution. The research proposed on the matching relation between the ball size and the quality of ground products is essential for improving the ground product quality and reducing energy consumption.

Experiment study of basalt fiber/steel hybrid laminates under high-velocity impact performance by projectiles

Due to their excellent impact resistance, fibre-metal laminates have been successfully applied in modern engineering industries, the construction of aircraft, vehicles, and ships. In this study, a ballistic impact test was performed on a basalt fibre/steel hybrid laminate using a 19 mm diameter steel ball fired by a one-stage gas gun. This is to analyse how lay-up structure, fibre volume fraction, laminated surface density, and laminate impact angle influence the ballistic impact performance. The results showed that, under normal penetration action, the ballistic limit velocity values for laminates with different lay-up structures were 3/2, 2/1 and 4/3 respectively, from high to low lay-up. For the 3/2 lay-up structure, when the fibre volume fraction increased, the ballistic limit velocity decreased, and when laminated surface density was increased, the specific energy absorption also increased, after the projectile penetrated the target plate. The results of the oblique penetration experiment showed that energy loss improved with penetration angle.

Converter sludge drying in rotating drum using hot steel balls

Converter sludge is a by-product of converter steelmaking and a secondary resource of recovery; however, it needs to be dried before recovery. Obtaining the expected results using traditional sludge drying technologies is difficult due to the special properties of converter sludge. In this research, we proposed a new rotating-drum-drying technology using hot steel balls. Steel balls are heated by the waste heat of metallurgical slag. This technology has the advantages of low cost, high efficiency and thorough drying, and can overcome the shortcomings of traditional technologies. This research explored the converter sludge drying in a drum through experiments. The effect of four operating parameters on the drying process was investigated, and the suitable model for the drying process was discussed. The operating parameters include sludge treatment mass (3.0/4.0/5.0/6.7/9.0 kg), steel ball (initial) temperature (300/500 °C), steel ball diameter (20/30/40 mm) and drum rotating speed (1/3/5/7 rpm). Results show that this proposed technology is feasible and efficient. Sludge drying can be accelerated by appropriately reducing the sludge treatment mass, increasing the steel ball temperature, increasing the steel ball diameter, and selecting an appropriate drum rotating speed. The Weibull model can better predict the drying process by comparing multiple models. The operating parameters have obvious relationships with the fitting parameters of the Weibull model.