Pair Of Rollers Research Articles

Tribological properties of dual-freedom sliding roller pairs with a loss of lubrication

PurposeThis paper aims to design a novel test device and study the wear properties and the thermal mechanisms of roller pairs in dual-freedom sliding contacts.Design/methodology/approachOn the transition process of lubrication regimes, experiments were conducted with various values of running speed and slip ratio obtained by two motorized spindles. Temperature and surviving time would be obtained of GCr15/GCr15 and DLC/GCr15 friction pairs. Micro photography was obtained with a PGI 3D stylus profiler and a confocal microscopy OLS4000-3D. An empirical mode decomposition method was used to eliminate measure errors.FindingsResults showed that, even with little initial lubricant, rolling/sliding pairs still rotated for a certain time. With the synthetic actions of the dual-freedom sliding, the loss of lubrication and the tilt, interesting helical grooves appeared. Sliding speeds had remarkable effects on survive time, temperatures and surface topographies. In addition, the equilibrium values of the temperature and the surface roughness were obtained in sufficient oil supply. Extreme wear-out conditions were obtained with starved lubrication. Diamond-like carbon coatings showed better heat resistance and better wear resistance.Originality/valueThis work would be critical for the life design and the heat treatment of rolling bearings in the full flood lubrication and the starved lubrication.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0164/

Pressure calculation in a roller pair

Pressure calculation in a roller pair

Development of Gender-Friendly Power Ribboner for Extraction of Green Ribbon/Bast from Jute Plants

ABSTRACT Jute (Corchorus Olitorius) universally recognized as a golden fiber is one of the important cash crops in eastern India. In jute plants apart from fiber, sticks also have diversified applications in various sectors. Therefore, an advanced fiber extraction machinery that can extract fiber through ribbon retting without breaking sticks is the need of the hour for jute-growing farmers. In the present study, a gender-friendly power ribboner has been designed, simulated, and developed by considering the anthropometric data of both male and female operators. The developed prototype consists of a pair of fluted crushing rollers with pressure absorbing unit, a pair of peeling rollers, a fiber conveyor, power transmission unit, and an electric motor. The structural analysis of the designed fluted crushing rollers showed that the designed model and selected material (nylon 66/6) can withstand 10 times more load than the actual. At the optimized conditions throughput capacity, extraction capacity, extraction efficiency, and ribbon losses of the developed prototype were obtained as 227 kg/h, 116 kg/h, 92.95%, and 5.3% respectively, while the overall desirability of 0.966 was achieved. Furthermore, with the adaptation of the developed machine, jute farmers can get approximately Rs. 525/quintal or 12% more income than the conventional practice.

Numerical simulation of macrosegregation in continuously cast slab with application of S-EMS and MR

A 3D numerical model was built to investigate the transport phenomena in slab continuous casting process to investigate the influence of strand electromagnetic stirring (S-EMS) combined with mechanical reduction (MR) on macrosegregation in continuously cast slab. The model was validated by measured strand surface temperature and magnetic induction intensity. The results show that the S-EMS with two pairs of electromagnetic stirring rollers in the opposite direction significantly affects the crater end profile and centerline carbon segregation in slab. The maximum solidification end position difference along the crater end profile of slab ΔL reduced from 0.82 m to 0.52 m, and the centerline carbon segregation is improved by the weak S-EMS, when the current intensity increases from 0 to 250 A. But, the maximum solidification end position difference along the crater end profile of slab ΔL increases from 0.52 m to 1.05 m, the carbon segregation at the 1/4 centerline length position near the right narrow side of slab deteriorates when the current intensity increases from 250 to 350 A. With the combined application of MR near the crater end of continuously cast slab, the solidification delay phenomenon caused by the S-EMS can be significantly improved. But, the solidification delayed cannot be suppressed with current intensity higher than 250A. Therefore, the harmonious application of weak stirring of S-EMS with current intensity of 250A and MR with reduction amount of 4 mm just before the crater end of slab is most benefit for the centerline carbon segregation improvement in continuously cast slab.

Improper sample preparation negatively affects near infrared reflectance spectroscopy (NIRS) nutrient analysis of ground corn

Near infrared reflectance spectroscopy (NIRS) is widely used in the feed industry for the determination of nutrient composition of feed ingredients and finished feeds. This technology is a useful tool that can provide instant nutrient values for nutritionists to make sure that feeds are manufactured to specification. However, to achieve proper nutrient estimations from NIRS, samples must be ground to a specific particle size for each evaluation. Previous studies have demonstrated that particle size (PS) of the sample may affect NIRS nutrient estimates of corn and other feedstuffs. Therefore, an experiment was conducted to evaluate the effect of corn PS on the accuracy of NIRS proximate nutrient estimations. Corn was ground using a 2-pair roller mill set at 8 different roller pair settings. Roller pair spacing ranged from 50.8 µm at setting 2 to 152.4 μm 152.4 µm at setting 6. Roller mill settings 3–2, 3–3, 4–3, 4–4, 5–4, 5–5, 6–5, 6–6 generated samples with mean PS of 693, 882, 968, 1750, 1877, 2862, 2911, and 3343 µm, respectively. A rotor grinder with a 500-mesh screen was used to grind corn to 267 µm, which served as a control for the study as it is the recommended method for feed sample preparation per NIRS equipment recommendations. An NIR spectrometer and Adisseo Precise Nutrition Evaluation software with a calibration for ground corn were used to determine dry matter, ash, crude fat, crude protein, and crude fiber from 3 replicate samples from each PS treatment. Data were analyzed as a 1-way ANOVA using the GLIMMIX procedure of SAS ver. 9.4 and least square means were separated using the PDIFF option at P ≤ 0.05. Samples ground with only the roller mill with PS larger than the control treatment were lower in dry matter, ash, and crude fat. Crude protein content of ground corn was also lower in samples with PS larger than the control except for samples ground to 3343 µm (6−6). In contrast, crude fiber was greater in samples with PS greater than the control treatment. Overall, the results of this study underscore the importance of proper sample preparation to obtain accurate nutrient content estimations from NIRS analysis.

Experiments and Analysis of a Peanut Semi-Feeding Picking Mechanism Based on the JKR Model

When peanuts are harvested, the high rate of pod crush and pods leakage are the main problems in the current peanut fruit picking process. Optimized peanut picking rollers help to improve peanut harvesting efficiency. This paper investigates the fruit picking system of a three-monopoly, six-row semi-feeding peanut combine harvester, in order to reduce the rate of crush and leakage of peanut pods during the picking process. Firstly, this article specifies the structure and basic parameters of peanut picking pairs of rollers. Secondly, this paper combines JKR (Johnson-Kendall-Roberts) model theory, crash model simulation analysis, a field test, and other methods. Motion and force analysis are presented in detail for the peanut picking mechanism and associated harvesting components. The optimum clamping chain speed, the angle of installation of the picking rollers to the clamping chain, and the picking rollers’ speed are determined. A three-factor, three-level regression orthogonal combination test was designed to obtain regression models for pod crushed and pods leakage rate. The regression model’s response surface analysis concluded that when the clamping chain speed is 0.84–1.2 m/s, the fruit picking roller angle is 10°–11.2° and the fruit picking roller speed is 442 r/min–500 r/min. It is the optimal working parameter for the three-monopoly six-row peanut combine harvester. At this point, the peanut harvesting requirements are met, and the overall performance is significantly improved. This paper lays the foundation for the development of the semi-feeding peanut picking system.

ЗНИЖЕННЯ ПРУЖНИХ ВЛАСТИВОСТЕЙ ЗАЛИШКІВ ЛЬОНУ ОЛІЙНОГО ЗА РАХУНОК ДЕКОРТИКАЦІЇ

Harvesting of oleaginous flax seeds creates a biomass of stem residues that needs to be processed or utilized. Many methods of processing this biomass into various products (fiber, fuel, composites, etc.) have been offered. The first step in processing oleaginous flax residue is spinning it into rolls. However, oleaginous flax stems have highly elasticity properties and quick recovering abilities which make residue processing difficult. This paper suggests methods of decreasing the elasticity properties of oleaginous flax residue by destroying the higher layer of stem – decortication. Elasticity properties are influenced by layer thickness, humidity, and the amount of flax breakage as it passes through the roller pairs of a roller machine (decorticator). An increase in humidity and in the number of passes through the decorticator makes elasticity properties decrease. It allows making rolls that will keep their shape for a long period without any additional influences. In the future, these rolls can be used as a fuel or for a longer processing. The research results show a correlation with the rational number of machine roller pairs which can be used to develop new engineering designs for oleaginous flax harvesting.

Non-Uniform Deformation of Slab during Heavy Reduction Process

The bulge deformation of slab narrow face can cause surface defects of hot rolled steel plate. A three-dimensional bulging model, was proposed to simulate the evolution of deformation behavior of the continuous casting slab during heavy reduction (HR). The model was taken to investigate the non-uniform deformation of slab during HR process. The bulging deformation behavior of the slab was then calculated in one segment included seven pairs of rollers. To improve the edge defect on hot-rolled steel plates, the relationship between the reduction amount and bulge deformation of slab narrow face has been investigated.

Dynamic Characteristics of a Variable Damping Isolator with Translating Cam

A variable damping isolator based on a translating cam designed especially is proposed in this paper. The nonlinear variable damping isolator is mainly comprised of translating cam with a pair of rollers arranged symmetrically and horizontally and two linear dampers. The damping force of this isolator increases with the increase of its vertical displacement. The dynamic equation is established when the variable damping isolator is applied to the active isolation system under simple harmonic excitation. And the dynamic response of the equation is obtained by Harmonic Balance Method. After that, the numerical simulations are conducted to discuss the effects of the parameters of the isolation system on force transmissibility. The results show that the effects on attenuating the resonance and the force transmissibility in the region of high-frequency ratio are superior to that of the corresponding linear damping vibration isolator when appropriate design parameters (cam profile and damping coefficient of the horizontal linear damper) of the variable damping isolator are selected.

Triacetin as Lubricant Additive: Slipping Friction between Metal Pairs under Boundary Lubrication

Friction between rubbing pairs plays a key role in operating machines in an efficient approach. In some intended works or occasional circumstances, slipping friction may occur during dry or boundary lubrication. Lubricating mechanical equipment using proper and efficient lubricant agents is tremendously necessary. This work explores the synthesized triacetin as an additive for lubricant under slipping friction between steel rollers and aluminum, brass, copper, and stainless-steel rods under boundary lubrication. The metal surface morphology under the lubricant with 10% triacetin additive covering roughness periphery is investigated by Field Emission Scanning Electron Microscope imaging. In the dry slipping condition, the friction coefficient is lower for the copper-steel pair compared to the aluminum-steel combination. Compared to the absence of triacetin additive, the steel roller combinations with the rod metal specimens undergoing boundary lubrication with 10% triacetin additive in the lubricant can reduce the slipping friction coefficient by up to 49.2% in the case of steel roller and brass rod pair. The quantitative influences of triacetin additive on metal rubbing pair friction coefficients under boundary lubrication are inversely exponential correlated to triacetin additive, varying in the range of 0 to 10% v/v.

Теоретичні дослідження силової взаємодії тривісного автомобіля зі стендом з одиночними роликами

The article discusses the issues of modeling conditions for obtaining diagnostic information about complex objects. Checking the braking and traction properties of three-axle trucks on a roller stand is considered as an example. As shown by many studies, in particular, which were carried out at the Department of Technical Operation and Service of Automobiles of the KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. Such stands allow you to reproduce the real speed and thermal conditions of the brakes. To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car's wheels with the rollers. The study of the rolling of the wheels of a three-axle car bogie on the stand rollers was carried out at the Department of Technical Operation of Cars, KhNADU. However, all these studies were carried out on biaxial stands, where each bogie wheel rests on a pair of rollers. In order to exclude wheel slippage, partial braking is recommended, that is, a mode when partial force on the pedals (or pressure) is created in the system and, as a result, incomplete braking force develops in the braking mechanisms (or deceleration reaches some partial value from the full one). It is necessary to analyze the possibility of implementing full brake test modes on a roller stand by improving the layout and geometrical scheme of the stand. A power model of the system of interaction between a car and a stand has been developed, taking into account the design features of the stand and the design features of the suspension of a three-axle car. The power model of this system includes the equations of equilibrium of the body and two axles, as well as the equations of motion for the rollers and wheels of the car. Based on the results of the analysis of the acting forces in the "car-stand" system, the coefficients of the use of the load q during the brake tests of a three-axle car were determined, and the longitudinal stability of the car was also analyzed. The obtained research results allowed to improve the theory of interaction of the wheels of three-axle vehicles with single rollers of the diagnostic stand.

Обґрунтування обладнання для збирання льону олійного зернозбиральним комбайном

Presentation of the results of experimental field research, laboratory to determine the conditions for harvesting oilseed flax stalks in the phase of full maturity. Outlining the conditions for the technological operation of harvesting oilseed flax by extracting stems from the soil. Presentation of the methodology for determining the necessary working elements of the equipment for extracting stems from the soil and forming the continuity of the flow of a group of stems on the harvesting part of the combine harvester. The problem that arises in the process of harvesting flax oil in the phase of full maturity is due to the presence of fiber in the stems, which complicates the work of the segmental-finger cutter. Therefore, the collection of such stems is carried out by the method of taking (extraction from the soil). This phenomenon requires the development of equipment for the universalization of the combine harvester, which increases its ability to be used in the harvesting of crops, taking into account the growing conditions and the state of the stalk. The experiments were conducted in the field on the Lyrina variety to establish the average value of the collection effort. The crops were not characterized by uniform ripening, which allowed to choose areas that characterized the maturity phases of oilseed flax. Start of research: mid-July, end - until 01.09. Accordingly, the study of the continuity of flow was conducted in the laboratory by simulating the selection of stems from one to five adjacent rows. It was found that a cylindrical support rough surface is required to ensure the continuity of the flow in the equipment. Based on the proposed structural and logical scheme, the main working units of the equipment to ensure high-quality harvesting of oilseed flax of any phase of ripeness without changing the design of the harvesting part of the combine harvester. These include: the mechanism of separation of portions of the stem from the total array and the picking device, which consists of pairs of rollers with horizontal axes of rotation and a distance between them of 76.2 mm. Combining the results of field and laboratory studies with the analysis of forces when moving the stem mass in the form of a flow of a group of stems on the supporting surface allowed to offer a constructive - layout scheme of equipment for harvesting oilseed flax. This equipment is intended to be installed on the harvesting part of the combine without changing its design. The analysis of forces performed for the flow of stems moving inseparably on a cylindrical support surface is important for the study of the selection of the stem mass of crops from rolls.

A Computational Analysis for Active Flow and Pressure Control Using Moving Roller Peristalsis

Peristaltic motion arises in many physiological, medical, pharmaceutical and industrial processes. Control of the fluid volume rate and pressure is crucial for pumping applications, such as the infusion of intravenous liquid drugs, blood transportation, etc. In this study, a simulation of peristaltic flow is presented in which occlusion is imposed by pairs of circular rollers that squeeze a deformable channel connected to a reservoir with constant fluid pressure. Naturally, this kind of flow is laminar; hence, the computation occurred in this context. The effect of the number and speed of the pairs of rollers, as well as that of the intrapair roller gap, is investigated. Non-Newtonian fluids are considered, and the effect of the shear-thinning behavior degree is examined. The volumetric flow rate is found to increase with an increase in the number of rollers or in the relative occlusion. A reduction in the Bird–Carreau power index resulted in a small reduction in transport efficiency. The characteristic of the pumping was computed, i.e., the induced pressure as a function of the fluid volume rate. A strong positive correlation exists between relative occlusion and induced pressure. Shear-thinning behavior significantly decreases the developed pressure compared to Newtonian fluids. The immersed boundary method on curvilinear coordinates is adapted and validated for non-Newtonian fluids.

An Investigation into the Effect of Rolling Reduction on 3D Curved Parts Rolling Process

Rolling technology based on arc-shaped rollers is a novel method for rapid manufacturing of 3D curved parts. The method uses a pair of arc-shaped rollers (a convex roller and a concave roller) as forming tools, forming an unevenly distributed roll gap. The sheet metal has both transverse bending and longitudinal uneven extension during rolling, so that surface parts with double curvature are processed. The curvature of the formed surface part can be changed by changing the rolling reduction. Changing the vertical distance between the rollers will cause the overall change of the roll gap height, which will inevitably have a great impact on the forming effect of formed 3D curved parts. In this paper, a finite element model and experiment with different rolling reductions was designed; the influence of rolling reduction on the bending deformation and shape accuracy of formed 3D curved parts was studied. The results show that, with the slight increase of rolling reduction (from 0.04 to 0.12 mm), the longitudinal bending deformation of the formed 3D curved part increases significantly, but its transversal bending is almost not affected. When the maximum rolling reduction is 0.04 and 0.06 mm (the corresponding minimum rolling reduction is less than or equal to zero), the shape accuracy of the formed 3D curved parts is not good enough; when the maximum rolling reduction is greater than 0.06 mm (the corresponding minimum rolling reduction is greater than zero), the shape accuracy of the formed 3D curved parts is significantly better. This indicates that, for the rolling of 3D curved parts based on arc-shaped rollers, ensuring that the minimum rolling reduction is greater than zero is the key to ensuring good shape accuracy of the formed 3D curved parts.

Influence of thickness reduction on the forming results in the three-dimensional surface rolling process with rigid arc-shaped rollers

Three-dimensional surface rolling with rigid arc-shaped rollers (TSRRAR), a new method for manufacturing double-curved metal sheets, can be used to realize the rapid forming of 3D surface sheets. The non-uniform roll gap is generated by a pair of rollers with different axial radii with appropriately reduced sheet thickness. After passing through the roll gap, a flat sheet is bent in the rolling direction. Meanwhile, it deforms perpendicular to the rolling direction, resulting in a three-dimensional surface part with curvatures in both directions. The work adopted the elastic-plastic finite element (FE) method to simulate aluminum alloy sheets with different maximum thickness reductions. The results showed that the longitudinal curvature of sheets rose as the reduction increased. Moreover, a slightly increased reduction caused a significant variation in the longitudinal curvature radius of sheets. Different bending curvatures of sheets could be obtained by changing the reduction, indicating the flexible forming of three-dimensional curved surface metal sheets. Also, the changing trend of longitudinal curvatures of testing parts obtained by rolling experiments was substantially in agreement with the FE simulation results. Therefore, the established FE models can be used for exploring the manufacturing process of TSRRAR.

Study of Adhesion Recovery phenomenon using a Multi-axle Roller-rig

When a railway vehicle is running on a contaminated track, the available friction is reduced, and large creep values arise at the wheel-rail interface. However, the work of the friction forces of the leading wheelsets produces a cleaning effect on both the track and the wheels, so that the contaminant layer is partially removed, and adhesion increases on the leading as well as on the trailing wheelsets. The investigation of these adhesion recovery phenomena is the key to develop new solutions aiming to improve the vehicle dynamic behaviour in degraded adhesion conditions. Since on-field tests are usually expensive and time-consuming, roller-rigs are the typical apparatus used to simulate the vehicle dynamic behaviour in laboratory conditions. The paper describes the mechanical design of an innovative roller rig specifically designed to study adhesion recovery phenomena, consisting of four wheelsets running over the same pair of rollers. Experimental tests are performed on the test bench to obtain adhesion characteristics under dry and contaminated conditions.

A Numerical and Experimental Study on the Solidification Structure of Fe–Cr–Ni Steel Slab Casting by Roller Electromagnetic Stirring

We present a segmented coupling model for slab casting by roller electromagnetic stirring (R-EMS) of electromagnetic, flow, heat transfer, and solidification behavior based on magnetohydrodynamics and solidification theory. A three-dimensional (3-D) segmented coupling model that included electromagnetic, flow, and heat transfer elements was established using Ansoft Maxwell and ANSYS Fluent software. The effects of the roller sleeve, magnetic shielding ring, coil, core, molten steel, and air domain on the electromagnetic, thermal and flow fields were studied numerically. The accuracy of the model was verified by measuring the magnetic flux density at the centerline in a pair of rollers and the electromagnetic force of the copper plate. Based on the numerical results of the optimal technical parameters, the effect of the R-EMS on the solidification of Fe–17 wt% Cr–0.6 wt% Ni stainless steel was explored. The results indicated that with each additional pair of electromagnetic rollers, the average electromagnetic force increased by 2969 N/m3 in the casting direction, and 5600 N/m3 in the central section of the rollers. With increasing number of pairs of rollers, the effective stirring region increased, and the velocity of molten steel at the solidification front first increased but then decreased. The strong electromagnetic swirling washing effect reduced the solidification rate of the slab shell and promoted the superheated dissipation of molten steel in the center of the strand. The center equiaxed crystal ratio of the slab was improved to 69% with two pairs of R-EMS rollers and electromagnetic parameters of 400 A/7 Hz, which was beneficial for obtaining a uniform and dense solidified structure to improve the subsequent hot working performance and product quality.

Automatic Orange Juice Vending Machine

The purpose of this project to construct automatically operated orange juice vending machine. The operation of this machine very easy comparatively to other machine, with good efficiency. The machine cost was less and easy to manufacture. Power consumption is low. We added one rotating wheel which can take orange one by one. The dimensions are 3 ft. height and 1.5 ft. in width and 1.5 ft. length. The two rollers and three blades are used to remove the juice from orange. A DC motors are used to drive the roller and blades and IR sensor sense the coin which we insert in the coin insertion box. The blades are used for the cutting purpose of orange. The two DC motors are used for rotating the blades and roller. In this machine does not required any other equipment to pressing action, for extraction of orange juice. Two blades are fitted parallel to each other and one blade below the parallel blade, due to this pressing action can achieve efficiently. The function of roller in this machine it can extract juice from small pieces of orange which crush by blades. The automatically operated mechanical unit consists of a pair of motors, relays, roller and blades. The gear casing was constructed using 2mm thickness of mild steel sheet. The electronic parts consist the control unit, sensor and relays. The 3 motors are attached with L293D motor driver IC which is controlled by 8051 microcontroller. The sensor is used for the monitoring the PH of juice.

ABOUT THE FEATURES OF THE PROCESS OF CIRCULAR PLASTIC COMPRESSION STRANDS

A simulation of the process of circular plastic compression of a strand of construction 1+6 by stretching in four pairs of rollers is carried out. It is established that the wires of the outer layer of the strand swell before entering the first pair of rollers, as well as selective formation of local areas of sharply increased plastic deformation on the outer surface of the wires.

Design and experimental study of the self-adaptive splitting technology of lotus seeds

The lotus plumule has high medicinal value and is an important part of the lotus seed. Usually, the lotus seed must be split symmetrically into two halves through a splitting process to obtain an intact lotus plumule. However, this process is difficult to mechanize and automate, as different lotus seeds are of different sizes. In this study, a novel automatic self-adaptive splitting technology (SAST) is proposed for lotus seeds, based on a specially designed combined linkage mechanism and a roller pair centering mechanism. The technology can automatically adjust the position of the splitting point taper punch according to the size of the lotus seed and ensure that the tip of the punch is on the axis of the lotus seed. First, the centering deviation of the centering mechanism was analyzed. A mathematical model for the SAST was developed, and the key parameters were optimized using the firefly algorithm. An automatic splitting machine and a test bench were designed for centering deviation measurements, and both centering and splitting experiments were conducted. The generated maximum centering deviation of the SAST was <0.176 mm; the highest accurate splitting rates of 95% and 93.05% were achieved for unclassified and graded lotus seeds, respectively.