Spinning Force Research Articles

A new spinning-extrusion forming technology for the inner-ribbed component

To solve the problem that the rib filling height is low in the traditional spinning forming (TSF) of ribbed component, a new spinning-extrusion forming technology (SEF) was proposed. A convenient device was built to conduct the SEF experiment, whose results show that the new SEF can greatly increase the rib filling height by 53% compared with the TSF. Moreover, the improvement mechanism and prediction model of rib filling height in the SEF were investigated. It is found that the rib filling in SEF is mainly dependent on two deformation stages: tension-shear deformation, which makes the material accumulate and bulge above the rib groove; compression-shear deformation, which makes the accumulated material fill into the rib groove. The final rib filling height is linear dependent on the material bulge amount in the tension-shear deformation stage. And, the improvement of rib filling by SEF lies in it can enhance the duration and deformation amount of tension-shear deformation stage, thus improve the material bulge amount in contrast to the TSF. On these bases, taking the material bulge region in SEF as object, slab method was used to analyze its deformation mechanics and establish the differential mechanical equilibrium equations; Thamasett method was adapted to calculate the spinning force; synthetically, the material bulge amount was theoretically calculated. Then, combing the linear relation between the material bulge amount and rib filling height, the model for prediction of rib filling height in the SEF was developed. The predicted rib filling heights under various processing parameters indicate that the rib filling height can be improved by increasing the extrusion force, thickness reduction rate, feed ratio and roller attack angle in the SEF.

Influence of Inner Roller Geometric Parameters on Counter-Roller Spinning with 6061 Aluminum Alloy Tube

The inner roller exerts a supportive and thinning effect on the inner side of the tube during counter-roller spinning. In this paper, the Finite Element Analysis (FEA) model of counter-roller spinning for a 6061 aluminum alloy tube was established based on the ABAQUS/Explicit module. The deformation characteristics and the influence of inner roller geometrical parameters on the tube spinning were analyzed. The results showed that the stress–strain on the outer of the tube was greater than that of the inner, and flaring was more prone to occur in the initial stage of counter-roller spinning compared to traditional mandrel spinning. The order of the effects of geometrical parameters of the inner roller on the roundness error and wall thickness deviation was as follows: nose radius > diameter > front angle. The order of factors influencing the inner and outer spinning force was as follows: diameter > nose radius > front angle. Increasing the diameter of the inner roller can improve the spinning stability and forming accuracy of counter-roller spinning. It was beneficial to improve the forming accuracy when the nose radius of the inner roller was slightly larger than that of the outer roller. The front angle of the inner roller has little influence on the spinning forming accuracy.

Effect of Process Parameters on Spinning Force and Forming Quality of Deep Cylinder Parts in Multi-Pass Spinning Process

In this paper, based on MSC Simufact.Forming v16.0 simulation software, the process parameters in the multi-pass spinning production of deep cylinders with a large diameter–thickness ratio are optimized, and the ten-pass spinning process of a deep cylinder with a diameter of 500 mm, thickness of 2 mm and depth of 700 mm is realized. By controlling the four process parameters of mandrel speed, feed rate, spinning wheel fillet radius and spinning wheel angle of attack, the influence of the four process parameters on the spinning force and the wall thickness deviation of the formed workpiece is studied. The results show that the radial spinning force and tangential spinning force are at their minimum when the mandrel speed, feed rate, spinning wheel fillet radius and spinning wheel angle of attack are 500 rpm, 1 mm/rev, 6 mm and 35°, respectively. At these setup conditions, the spinning efficiency is the highest and the workpiece is not prone to defects. The wall thickness deviation of the workpiece will decrease with the increase in the mandrel speed; with the increase in the feed rate, the radius of the round corner and spinning wheel angle of attack, the wall thickness deviation increases first and then decreases.

A simplified model for the impact of dielectric polarization of a charged droplet on its diffusiophoresis

This study aims to quantify the impact of the dielectric permittivity of a droplet on its diffusiophoresis in different types of electrolytes. The dielectric droplet polarizes by the diffusion field along with the local electric field created by the interactions of the double layer with the imposed ionic concentration gradient, which generates an induced surface charge density anti-symmetrically distributed on the droplet surface. This induced surface charge influences both electrophoresis and chemiphoresis parts. Based on a low imposed concentration gradient, a simplified model is derived through a first-order perturbation technique. Dielectric polarization of the droplet attenuates the spinning force at the interface. This creates the mobility of a droplet of higher dielectric permittivity in the presence of a stronger diffusion field significantly higher than that of a perfectly dielectric droplet, and its value depends on the polarity of the droplet surface charge. In the absence of the diffusion field, the mobility of a conducting droplet remains a positive immaterial of the polarity of its surface charge density. We find that the impact of the dielectric polarization becomes significant as the surface charge density increases and attenuates with the increase in droplet viscosity. For a dielectric droplet at a thinner Debye length, a step-jump in mobility occurs at a higher value of the surface charge density. Such a type of step-jump in mobility does not appear for the conducting droplet due to the absence of the Maxwell stress at the interface.

A Study of Large Sheave Counter-Roller Spinning Force

In this paper, a counter-roller spinning method is presented, which is designed to produce relatively thin-walled large sheaves. The large sheave counter-roller spinning force is poorly studied. And the forming forces have a significant influence on industrial applications. Herein, theoretical analysis and numerical simulation methods were utilized to explore the large sheave counter-roller spinning process and spinning force. Anisotropy of the material was considered by the Hill-48 anisotropic yield criterion. Numerical simulation has been demonstrated to correspond to experimental values. The spinning forces in the simulation and experiment matched well and steadily increased throughout the process. The roller and mandrel have similar spinning forces, and the radial spinning force is much larger than other forces. Finally, a theoretical model to compute the spinning force was constructed.

Effect of Alternating Magnetic Field on Arc Plasma Characteristics and Droplet Transfer during Narrow Gap Laser-MIG Hybrid Welding

In this paper, the morphological characteristics of arc plasma and droplet transfer during the alternating magnetic field-assisted narrow gap groove laser-MIG (metal inert gas) hybrid welding process were investigated. The characteristics of arc plasma and droplet transfer, electron temperature, and density were analyzed using a high-speed camera and spectrum diagnosis. Our results revealed that the arc maintained a relatively stable state and rotated at a high speed to enhance the arc stiffness, and further improved the stability of the arc under the alternating magnetic field. The optimum magnetic field parameters in this experiment were B = 16 mT and f = 20 Hz, the electron temperature was 9893.6 K and the electron density was 0.99 × 1017 cm−3 near the bottom of the groove, which improved the temperature distribution inside the narrow gap groove and eliminated the lack of sidewall fusion defect. Compared to those without a magnetic field, the magnetic field could promote droplet transfer, the droplet diameter decreased by 17.6%, and the transition frequency increased by 23.5% (owing to the centrifugal force during droplet spinning and electromagnetic contraction force). The width of the weld bead was increased by 12.4% and the pores were also significantly reduced due to the stirring of the magnetic field on the molten pool.

Research on the Influence of Main Spinning Process Parameters on the Forming Quality of 20 Steel by Strong Spinning

With the continuous development of spinning technology, more and more products are processed by spinning. Every time spinning a new product, it is necessary to reset the spinning process parameters, which are usually determined by spinning process test. If the influence of spinning process parameters on the forming quality can be grasped, it can help the rapid setting and optimization of spinning schemes. In this paper, through a large number of spinning process tests, the effects of spindle speed and feed rate on the strength of 20 steel were analyzed, including the defects such as corrugation, cracking, and diameter expansion, as well as the spinning force, roundness and nominal diameter tolerance. The research results of this paper have certain scientific significance for the reasonable setting of process parameters of 20 steel, and provide theoretical basis for the optimization of spinning process parameters.

Neck-spinning quality analysis and optimization of process parameters for plunger components: Simulation and experimental study

The plunger component is a key part of the plunger pump in the aircraft hydraulic system. Neck-spinning process is commonly used to fabricate plunger components, of which the quality of the spinning process significantly affects the performance of plunger pumps. One of the bottlenecks faced by the industry in the spinning process is to choose a suitable neck-spinning process so as to ensure the quality of plunger components. It is necessary to propose a reliable method to optimize the process parameters which affect the neck-spinning quality of plunger components. In this study, a calculable finite element analysis (FEA) model is established to simulate the three-roller neck-spinning process of the plunger component, which includes six typical slipper structures, two roller structures, and two spinning parameters. The FEA model is then validated by comparing the simulated spinning forces with the corresponding experimental results. The influence of the process conditions on the neck-spinning quality is investigated. And the orthogonal simulation results are analyzed by a combination of range method and fuzzy mathematical analysis method to recommend a reasonable slipper structure, roller structure and neck-spinning parameters. This study provides a promising method to improve the manufacturing quality of the typical plunger components.

Prosthetic Leg Model

The main goal of this paper is to introduce an imitated prosthetic leg model by analyzing the applied forces. Even though the model is based on the idea of a prosthetic leg, it is also applicable to people without disabilities. The same concept of the model can be seen in the circus, where a person maintains a balanced state while on an incredible height without falling. When all the applying forces in the system are calculated, the design achieves the ideal state which allows it to function most effectively. One of the essential factors applied to the imitated prosthetic leg model, that causes a great impact on the human body’s movement, is torque. Torque is proportional to the spinning force that tends to cause rotation about a certain axis. Therefore, the paper also focuses on the idea of moment of inertia and center of mass to estimate torque. The density of different materials is also considered and compared in order to provide insights as to which would be the most effective.

Quality prediction of plunger components based on the finite element method during the neck-spinning process

To improve the neck-spinning processing quality of plunger components, a reliable finite element (FE) model was established and validated by the experimental spinning force. In the advanced FE model, an additional analysis step was added to obtain the pulling-out force, the axial clearance, and the swing angle of the plunger components after the neck-spinning process. Thus, the neck-spinning quality of the plunger components can be predicted. The results show that the simulated results using the FE model agree with the experimental results very well. The radial and axial spinning forces are approximate 3 and 2 times of the tangential spinning force, respectively. Finally, the influences of spinning parameters (e.g., feed rate and rotating speed) on the finished pulling-out force, axial clearance, and swing angle were evaluated in detail. The pulling-out force increases with increased feed rate, which tends to be stable with increased rotating speed. Compared with the stable tendency of axial clearance affected by feed rates, the axial clearance decreases significantly with increased rotating speeds. The swing angle of plunger components remains stable with different feed rate and rotating speed after the neck-spinning process.

Research on counter-roller spinning force based on finite element simulation and experiment

Counter-roller spinning is an effective method for forming large metal cylindrical parts. In this paper, the radial, axial and tangential counter-roller spinning forces were analyzed. The simulation analysis model was established and the counter-roller spinning was simulated based on the commercial FEA software, SIMUFACT-FORMING. The influence of different thinning ratio, feed rate and forming angle of roller on spinning force was analyzed. It can be seen that the deviation between the simulation average radial spinning force and the experiment average radial spinning force was less than 12%, and that of the axial spinning force is less than 10.5%, which can effectively guide the spinning process test.

Research on the power spinning method of large high-strength cylindrical parts

Counter-roller spinning is an effective method to form large metal cylindrical parts due to its small forming force, low mold cost, and flexible processing. A finite element (FE) simulation model of counter-roller spinning was established by Simufact Forming software to process a tubular blank with an internal diameter of 1970 mm and wall thickness of 26 mm. The simulation results show that the radial spinning force of the inner and outer rollers is minimum, and the difference of the radial spinning force between the outer roller and inner roller is smallest when the process parameters are as follows: thinning ratio of the tubular blank Ψt = 20%, forming angle of the roller αρ = 25°, feed rate of the roller f = 1 mm/r, and pairs of rollers m = 4. Comparatively, the average radial spinning force of mandrel spinning is about 1.70 times that of counter-roller spinning. In the stable spinning stage, the equivalent strain difference decreased gradually with the increase of the thinning ratio and increased steadily with the increase of the forming angle of roller. As the feed rate of the rollers increased, the ovality of the workpiece tended to decrease gradually, the deviation value of outside diameter also decreased progressively, and the straightness accuracy increased. The results of the counter-roller spinning experiment show that a mouth-expanding defect exists in the workpiece, which is consistent with the simulation results. In addition, the internal surface quality of the workpiece was better than the external surface quality under the same feed rate. If the feed rate is not reduced, the surface quality will continue to deteriorate as the pass number of spinning increases. After the cumulative thinning ratio of 30CrMnSiA alloy, structural steel reached 69%; the workpiece surface exhibited a peeling defect and required annealing before spinning could be continued. In addition, the deviations between experimental and FE results of the average radial spinning force and the ovality and straightness were less than 12% and less than 15%, respectively.

Numerical Simulation of Stagger Spinning for D406A High-Strength Steel

Metal spinning process is widely used because of its low power requirement to producing complex symmetry components. In this paper, a modified 3D finite element(3D-FE) model is developed under the FE software environment based on characteristics of stagger spinning process. Analysis of the multi-pass spinning deformation mechanism and the effects of spinning parameters on spinning deformation is carried out. The results show that, large internal diameter of tube blank and low dimensional accuracy are caused by too little feed rate of spinning roller, especially for thin-walled tube. But if the feed rate is larger than 60mm/min, large spinning forces and instability appear. Strain rate and forming instability increase with the increase of rotational speed of mandrels, on the other hand, more obvious friction leads to bigger strain of surface of tube blank. With the radius of corner of spinning roller getting 13mm, the extensive overlaps lead to the improvement of spinning efficiency, while low forming quality accompanied by the large spinning forces occurs. Cutting phenomena leads to worse surface quality even tends to crack with the radius of corner of spinning roller being smaller than 8mm. An ideal combination of process parameters is obtained: the roller feed rate is 50mm/min, the rotational speed of mandrel is 40rad/min, the radius of corner of spinning roller is 10mm.

Plastic Deformation Mechanism in Double-Roller Clamping Spinning of Flanged Thin-Walled Cylinder

Double-roller clamping spinning (DRCS) is a new process for forming a thin-walled cylinder with a complex surface flange. The process requires a small spinning force, and can visibly improve forming quality and production efficiency. However, the deformation mechanism of the process has not been completely understood. Therefore, both a finite element numerical simulation and experimental research on the DRCS process are carried out. The results show that both radial force and axial force dominate the forming process of DRCS. The deformation area elongates along the radial direction and bends along the axial direction under the action of the two forces. Both the outer edge and round corner of the flange show the tangential tensile stress and radial compressive stress. The middle region shows tensile tangential stress and radial stress, while the inner edge shows compressive tangential stress and radial stress. Tangential tensile strain causes a wall thickness reduction in the outer edge and middle regions of the flange. The large compressive thickness strain causes material accumulation and thus, an increase in the wall thickness of the round corner. Because of bending deformation, the round corner shows a large radial tensile strain in addition. The inner edge of the flange shows small radial compressive strain and tensile strain in thickness. Thus, the wall thickness on the inner edge of the flange continues to increase, although the increment is small. Furthermore, microstructure analysis and tensile test results show that the flanged thin-walled cylinder formed by DRCS has good mechanical properties. The results provide instructions for the application of the DRCS process.

Three-directional contact force model for the ball spinning of a thin-walled tube

This paper provides a computational model for calculating three-directional ball spinning force in accordance with the theory of space analytic geometry. The contact boundary equation of the ball and tube is obtained. By projection, the two-dimensional curve in each coordinate plane is acquired. The projected area of the contact zone in the coordinate plane is calculated through the curve integral. It is assumed that the average pressure of the forming region is nearly equal to that when the steel ball is pressed into the tube. Hence, the unit pressure of the deformation zone is obtained. Then, the spinning component force and total spinning force are calculated. Using a Tu1 thin-walled tube of oxygen-free copper as experimental object, a ball spinning experiment is conducted, the axial spinning components force are tested and the ball spinning force calculation model is verified. Based on deformation rate, backward sliding accumulation and extension and frictional heating, the factors influencing calculation error are analysed at the end of this paper.

Influence of microfluidic flow rates on the propagation of nano/microcracks in liquid core and hollow fibers

Melt-spinning is a conventional method for the production of synthetic fibers. The development of melt-spun liquid core or liquid filled fibers in which the liquid component is already incorporated during fiber spinning has been reported as a viable alternative to traditional hollow fibers. The elucidation of the mechanical behavior of this new type of bicomponent fiber is of interest, with particular emphasis on its fracture mechanics. In this paper we describe a microfluidics method used to induce liquid flows through these fibers (internal diameter 15–30 μm), aiming at analyzing the influence of flow rate on crack formation and/or propagation. Although only a very small number of fibers show the presence of cracks (1–4% of the tested specimens), it is possible to establish a clear correlation between flow rate and the appearance of cracks. The main fracture mechanism found to be operating in these melt-spun fibers is the type I (opening mode) fracture, evidenced as the internal pressure exerted by the liquid being injected through the fibers increases during microfluidic testing. As fiber spinning and drawing force the polymer chains that compose the sheath to be preferentially oriented in the fiber direction, the formation of axial cracks over transverse cracks is favored due to a lack of strong intermolecular interactions between polymer chains in the transverse direction of the fiber.

The finite element simulation analysis research of 38CrSi cylindrical power spinning

In order to grope for the influence of the main cylindrical spinning process parameters on the spinning process, this paper combines with real tube power spinning process and uses ABAQUS finite element analysis software to simulate the tube power spinning process of 38CrSi steel materials, through the analysis of the stress, strain of the part forming process, analyzes the influence of the thickness reduction and the feed rate to the forming process, and analyzes the variation of the spinning force, finally determines the reasonable main spinning process parameters combination.

A study of severe flange wrinkling in first-pass conventional spinning of hemispherical part

Flange wrinkling is one of the most common defects in conventional spinning. Slight wrinkles can be eliminated by a reasonable design of the spinning process parameters or assisted process, while severe wrinkles lead to low forming quality or even defective products. A lot of work has been done to find the reason for flange wrinkling and the way to avoid it, while limited research has been done to study the severe flange wrinkling phenomenon in conventional spinning process. In this paper, the severe flange wrinkling phenomenon in first-pass conventional spinning of the hemispherical part has been studied through FE (finite element) simulations and experiments. A double curved surface buckling prediction model based on the energy method is proposed in order to predict severe flange wrinkling. Experiments are designed to verify the theoretical severe flange wrinkling prediction method. It turns out that the wrinkling of the inner compressive stress ring leads to the severe fluctuations of the spinning force, and it can be taken as a sign of severe flange wrinkling in the conventional spinning process. Furthermore, the effects of flange wrinkling on the spinning qualities of the final formed hemispherical parts are researched. It is concluded that slight flange wrinkles in the first-pass have little effects on thickness distribution and geometry accuracy of the final formed part, while severe flange wrinkles lead to failed products. Severe flange wrinkling prediction is significant for the conventional spinning of the hemispherical part.

Spinning Process Design Using Finite Element Analysis and Taguchi Method

Abstract Metal spinning process is widely used because of its low power requirement to producing complex symmetry components. Spinning process parameters influence the spinning force and wall breakage or wrinkling problems of finished parts. The experimental and numerical simulation of metal sheet spinning has been applied to investigate the effect of spinning process parameters in order to achieved lower force and large deformation without the wall breakage or wrinkling failure. In the study, Taguchi method is implemented in cooperate with finite element analysis to reduce the number of numerical simulation. The spinning experiments were carried out on a modified turning lathe to accommodate a Kreisler force transducer to measure spinning forces. The three dimensional finite element model of sheet metal spinning was developed using the same spinning experiment process parameters. The SPCC sheet metal workpiece is modelled as an isotropic elastic-plastic material. The average predicted spinning force was 853 N. There is an error of 6.25% in the FE model prediction. Furthermore, the predicted thicknesses of the deformed part were compared with the measured experimental parts thickness and the error was 6.06%. It is clear that the finite element model results agreed well with the spinning experimental results. The effect of eight process parameters, i.e. roller radius, spindle speed, feed rate and feed depth, friction coefficient, width of support roller, diameter of support roller and angel of mandrel slope, on spinning force and deformation were studied. Finite element analysis of Taguchi-L18 spinning experiment were carried out. Taguchi main effect analysis and ANOVA results show that the slope of mandrel, spinning depth and support roller width are the most important factors influencing the spinning force. The slopes of mandrel, spinning depth and roller radius are the most important factors influencing the thickness variation of deformed parts. The roller radius, spinning depth and support roller width are the most important factors influencing the severity of wrinkling failure.

Influence of roller distribution modes on spinning force during tube spinning

The eccentric force exerted on the mandrel by the rollers has important influence on the forming precision of tubular workpieces during tube spinning, which is closely related to the roller distribution mode. In this study, the deformation characteristics and spinning forces were investigated during tube spinning with different roller distribution modes. According to the simulation results, the contact zones under the rollers were analyzed and the spinning forces applied by various rollers were obtained. The results show that the stress distribution exhibits non-periodic change along circumferential direction and the spinning forces of various rollers are different because the non-uniform distribution of the rollers leads to different contact zone areas under the rollers. The variation of spinning forces of the rollers causes the unbalanced load exerted on the mandrel, thus the mandrel deviates from the neutral axis, which is verified by the deflection measurement of the mandrel end in the spinning experiment. Although the spinning forces of the rollers on the same side are different, four-roller spinning can keep the balance of the mandrel. In addition, stagger spinning with nonuniformly distributed three rollers is newly proposed to achieve the balance of the mandrel, increasing the flexibility of traditional two-roller spinning machine.