Feed Screw Research Articles

Research on Global Nonsingular Fast Terminal Sliding Mode Control Strategy of Ball Screw Feed System Based on Improved Double Power Reaching Law

Research on Global Nonsingular Fast Terminal Sliding Mode Control Strategy of Ball Screw Feed System Based on Improved Double Power Reaching Law

Influence of Twin Screw Extrusion Conditions on MWCNT Length and Dispersion and Resulting Electrical and Mechanical Properties of Polycarbonate Composites

The processing conditions were varied during the production of polycarbonate-based composites with the multiwalled carbon nanotubes (MWCNTs) Baytubes® C150 P (Bayer MaterialScience AG, Leverkusen, Germany), by melt mixing with an extruder on a laboratory scale. These included the screw design, rotation speed, throughput, feeding position and MWCNT content. Particular attention was paid to the shortening of the MWCNT length as a function of the conditions mentioned. It was found that there is a correlation between the applied specific mechanical energy (SME) during the melt mixing process and MWCNT dispersion, which was quantified by the agglomerate area ratio of the non-dispersed nanotubes based on optical microscopic analysis. The higher the SME value, the lower this ratio, which indicates better dispersion. Above an SME value of about 0.4 kWh/kg, no further improvement in dispersion was achieved. The MWCNT length, as measured by the quantitative analysis of TEM images of the MWCNTs dissolved from the composites, decreased with the SME value down to values of 44% of the original MWCNT length. At a constant loading of 3 wt.%, the tensile strength and tensile modulus were almost independent of the SME, while the elongation at break and notched impact strength showed an increasing trend. The variation in the feeding position showed that feeding the MWCNTs into a side feeder led to slightly better electrical and mechanical properties for both types of MWCNTs studied (Baytubes® C150 P and Nanocyl™ NC7000 (Nanocyl S.A., Sambreville, Belgium)). However, feeding into the hopper led to better CNT dispersion with Baytubes® C150 P, while this was the case with Nanocyl™ NC7000 when feeding into the side feeder. The screw profile had an influence on the dispersion, the MWCNT length and the electrical resistance, but only to a small extent. Distributive screws led to a greater shortening of the MWCNT length than dispersive screws. By varying the MWCNT content, it was shown that a greater MWCNT shortening occurred at higher loadings. Two-stage masterbatch dilution leads to stronger shortening than composite production with direct MWCNT incorporation.

Effects of Barrel Temperature, Screw Speed and Feed Moisture Content on the Organoleptic Properties of Aerial Yam-Soybean Flour Extruded Snacks

The effects of barrel temperature, screw speed and feed moisture content, as extrusion process parameters, on the organoleptic properties of aerial yam-soybean flour extruded snacks were investigated, using Response Surface Analysis. The extruded snacks were produced using a Laboratory scale single-screw food extruder. Results of the determination of organoleptic properties of the extruded snacks showed that: texture; taste; colour; and aroma ranged from 4.38 to 6.02; 4.68 to 6.78; 4.58 to 6.97; and 4.45 to 7.00, respectively. Response surface Analysis indicated that barrel temperature and screw speed had significant effect (p < 0.05) on texture, while feed moisture had no significant effect (p > 0.05) on the texture of the snacks. All the extrusion parameters had significant effect (p < 0.05) on the taste of the snacks. Barrel temperature and feed moisture had significant effect (p < 0.05) on colour, while screw speed showed non-significant effect (p > 0.05) on the colour of the snacks. Barrel temperature had significant effect (p < 0.05) on aroma, while screw speed and feed moisture had no significant effect (p > 0.05) on the aroma of the snacks. The results obtained for the organoleptic properties of the snacks can attest to the fact that it is possible to obtain expanded or ready-to-eat (RTE) products from aerial yam-soybean flour blends by extrusion processing technology, that possess desirable organoleptic properties.

Impact Mill

An impact mill has been developed to produce powders from shavings of refractory metals using impact grinding method for reuse in electrometallurgy in devices with screw feed, for example, in 3D printers. The proposed device provides high uniformity of grinding with a minimum content of dust fraction and impurity content at low technical and economic costs. The result is achieved by using a Laval nozzle, which operates in the supersonic jet formation mode. In the area of the first Mach disk there are rod fenders arranged in a cascade, and the impact plate is located in the turbulence zone and is equipped with winglets with holes for separating crushed metal.

A new DEM calibration method for wet and stick materials based on the BP neural network

The assessment of flow characteristics and the Discrete Element Method (DEM) calibrations for Wet and Sticky Materials (WSMs) are significantly demanded by the mining and transportation industries. However, the angle of repose (AoR), as a common DEM calibration method, has been facing challenges in adopting for WSMs. Due to the relatively high adhesion and cohesion of WSMs, it is difficult to form repeatable material heaps, resulting in inaccurate measurements of the AoRs. Therefore, this study aims to calibrate DEM parameters for WSMs under various conditions, utilizing a modified AoR test method and the Back Propagation-Neural Network (BP-NN). In the modified AoR test method, WSMs are discharged from a funnel using a screw feeder and fall closely against a vertical baffle to form a heap in a constrained direction. The new method combines the features of the traditional AoR test and the slump plane test to accurately measure the AoRs for different WSMs, including wet white sand, bulk coal, and corn powders. Test results are analysed to show the advantage of the modified AoR test. Furthermore, an innovative DEM calibration method based on the BP-NN is developed. By training the BP-NN with the database established according to the relationship between the measured and simulated AoRs, the DEM calibration parameters can be predicted rapidly for WSMs with different particle sizes and moisture contents. Validation is conducted for the wet white sand, from which the deviations and relative mean deviations between the experiment AoRs (Ae) and the calibration AoRs (Ac) are less than 2°and 4 % respectively, indicating the capability of the developed method for WSMs DEM calibrations.

牛场补饲推料装置设计与试验

This paper proposed a supplemental feeding pusher based on beef cattle's auxiliary feeding needs to solve the traditional feeding mode of manual work, labor intensity, and inconsistent manual work standards. Firstly, the conveyed feed particles movement process was established as a motion model and the basis of the design parameters of the screw conveyor was explained. ANSYS static analysis module was used to ensure that the structural parameters of the discharging device were reasonable, ANSYS vibration modal analysis module was used to verify the frame strength and stability. According to the theoretical design of the trial prototype, the control system with STM32F103RE microcontroller as the core was carried out. Finally, the orthogonal test was conducted with the screw shaft speed, sweeping roller brush height, and traveling speed as test factors; different parameters were set to verify the effect of supplemental feeding and pushing, and parameter optimization of the test results was carried out using Design-Expert software. The optional combination of working parameters was determined to be the feeding screw shaft speed 188 r/min, the sweeping roller brush speed 160 r/min, and the work speed 0.26 m/s. The test demonstrated that the residual feed width was 0.73 m, and the transverse coefficient of variation was 14.9%, which could satisfy the needs of auxiliary feeding for beef cattle. This study reduced feed waste and met the cattle feeding needs to the greatest extent, and it could provide a reference for auxiliary feeding machinery.

Active prediction compensation strategy: A new positioning compensation technique for improving the accuracy of the dual ball screw feed mechanism under load

The dual ball screw feed mechanism (DBSFM) is commonly employed in high-end machining applications. However, its accuracy is challenging to enhance due to variations in the axial stiffness of the dual actuators under load, making geometric error compensation (GEC) difficult. To address this, our research establishes a comprehensive error model that integrates geometric error and load-induced error (LIE) to improve feeding accuracy. The axial stiffness matrix of the DBSFM is identified using motor current information, and an active prediction error matrix is defined based on the geometric error model, milling force model, and axial stiffness matrix. We propose and analyze the active prediction compensation (APC) strategy as a new method to enhance accuracy under load. Experimental validation using a gantry-type machine tool demonstrates that the APC strategy can reduce the positioning error of the DBSFM to ±2 μm under load, representing significant improvements over the established GEC method. Specifically, the APC strategy achieves a 53.07% and 57.04% enhancement in accuracy along the two axes. This work illustrates the effectiveness of the APC strategy in reducing positioning errors and improving feeding accuracy in DBSFM machining processes.

Impact of surfactant raw material variability on extrudate clarity appearance (transparency) in HME continuous manufacturing

The appearance of an extrudate formulation was monitored during hot-melt extrusion (HME) continuous manufacturing over 3 days. The formulation matrix consisted of a polymeric component, copovidone, and a low molecular weight surfactant, polysorbate 80. Based on studies prior to the continuous manufacturing, the desired appearance of the target extrudate is translucent. Although process parameters such as feed rate and screw speed were fixed during the continuous manufacturing, the extrudate appearance changed over time from turbid to translucent. For root-cause investigation, the extrudates were analyzed offline by differential scanning calorimetry (DSC) and advanced polymer chromatography (APC™). Although the polysorbate 80 content of both turbid and translucent extrudates was within target, the glass transition temperature of the turbid extrudate was 2 °C above expected value. The observed turbidity was traced to lot-to-lot variability of the polysorbate 80 used in the continuous manufacturing, where APC™ analysis revealed that the relative content of the low molecular weight component varied from 23% to 27% in correlation with the evolution from turbid to translucent extrudates. This work stresses the importance of taking feeding material variability into account during continuous manufacturing.

Modeling the Discharge Rate of a Screw Conveyor Considering Hopper–Conveyor Coupling Parameters

Developing a flow rate model for the screw feeder and optimizing discharge performance are crucial for achieving automated intelligent precision feeding. This study constructs a mass flow rate model for screw conveyors, considering the coupled structural parameters of the hopper and screw conveyor. The model is developed using single-factor tests and central composite design (CCD) response surface tests and is validated through actual discharge tests. Results indicate that the discharge rate in the hopper–screw conveyor system is primarily influenced by the screw conveyor itself. Among the structural parameters, the hopper inclination angle and the hopper discharge opening length significantly affect the filling coefficient. Validation tests show an average error of 6.8% between the predicted and simulated mass flow rates and 5.0% with the actual mass flow rate, demonstrating the model’s high precision and accuracy.

Investigating extrusion impact on functional, textural properties, morphological structure, and molecular interactions in hulless barley-based extruded snacks supplemented with mung bean.

The effect of varying extrusion conditions on the functional properties of hulless barley-mung bean (70:30) extruded snacks was investigated using response surface methodology with feed moisture (FM), barrel temperature (BT), and screw speed (SS) as process variables. Results revealed significant impacts on functional characteristics with varying extrusion conditions. Bulk density (BD) of extruded snacks ranged from 0.24 to 0.42 g/cm3, showing that lower FM and higher BT results in lower BD while it increased with increasing FM, SS, and BT. The expansion ratio (ER) of extruded snacks ranged between 2.03 and 2.33, showing BT and SS had a desirable positive effect, whereas increasing FM led to decreased ER. Increasing BT and SS depicted a negative effect on water absorption index, whereas FM showed positive effect, which ranged between 4.21 and 4.82 g/g. A positive effect on water solubility index was depicted by BT and SS, which ranges between 9.01% and 13.45%, as higher SS and BT led to starch degradation and increased solubility suggesting better digestibility. The hardness of extruded snacks ranged from 32.56 to 66.88 Newton (N), showing increasing FM increased hardness, whereas higher SS and BT resulted in lowering the hardness. Scanning electronic microscope (SEM) analysis revealed structural changes in extrudates in comparison with nonextruded flour, indicating starch gelatinization and pore formation affected by varying processing parameters. Shifts in absorption bands were observed in Fourier transform infrared spectroscopy (FT-IR), suggesting structural changes in starch and protein. Understanding the effects of extrusion parameters on product properties can help tailored production to meet consumers' preferences and the development of functional snacks with improved nutritional quality.

Powder agglomeration in continuous powder feeding by twin-screw feeder

The presence of powder agglomerates results in product with poor content uniformity and intermittent high potency in the processing of pharmaceutical powders.We developed a novel and easy-to-implement methodology, applying image analysis, to quantify the size of powder agglomerates when a powder passes through a screw feeder. Subsequently, agglomeration tendencies of twenty-one pharmaceutical powders were examined and classified. Notably, both the size and endurance of agglomerates were quantified, and our study revealed that the agglomeration tendency of powders can be explained by particle size and compressibility: Powders with small particle size (D50 < 30 μm), and large compressibility (> 35% at 15 kPa normal stress) tend to form large and enduring agglomerates, which can be difficult to eliminate in downstream processes. The study also illustrates how two materials, one that produces enduring and the other unenduring agglomerates, display substantially different content uniformity in the final product after being processed semi-continuously.

A novel screw-type pyrolysis system for selectively producing value-added chemicals from lignocellulosic biomass

AbstractIn this study, a new unique screw-type (auger) reactor system was developed to selectively obtain valuable chemical-enriched liquid pyrolysis products. The new design has heating segments with increased temperature along the reactor tube and three-staged fractional condensing lines following pyrolysis gas ports at the end of each heating segment. To maximize liquid product yield, the effects of some parameters such as feeding rate, screw rate, and temperature profile were studied by the experiments designed with Response Surface Methodology (RSM). By fixing the maximum temperature at the last heating segment of a tubular reactor to 550 °C, the conditions for maximum liquid product yield were determined as feeder driver frequency of 21 Hz (13.6 rpm), auger driver frequency of 36 Hz (24.3 rpm), and ΔT (temperature difference between consecutive heating segments) of 66 °C. Biomass feeding rate and volumetric fullness ratio of the reactor at these conditions were 42 g min−1 and 0.58 (v/v), respectively. Under these conditions, total liquid, solid, and gas product yields were obtained as 57%, 19%, and 24%, respectively. In addition, analyses of the liquid fractions showed that valuable chemicals could be obtained selectively in a large extent by using the new design.

Effect of Extruder Configuration and Extrusion Cooking Processing Parameters on Selected Characteristics of Non-Starch Polysaccharide-Rich Wheat Flour as Hybrid Treatment with Xylanase Addition

The effects of a single-screw extruder configuration and processing variables such as conventional extrusion or hybrid treatments with xylanase were tested on the extrusion performance and selected characteristics of the developed non-starch polysaccharide-rich (NSP-rich) wheat flour. L/D 16 and 20 extruder configurations with various screw profiles were used. The interactions between processing variables (moisture content 23, 25, 27%; screw speed 40, 60, 80 rpm; xylanase level 0, 50, 100 ppm) were assessed to indicate energy consumption and the rheological properties of flour. The results showed that the possibility of obtaining enzyme-assisted extruded flour products derived from flours of varying characteristics depended on the processing conditions. The application of various extruder configurations and screw profiles showed significant effects on both processing behavior and rheological characteristics. The longer L/D 20 extruder configuration using a screw profile with mixing elements allowed us to obtain products with lower extrusion pressure (max. 20.8 bar) and energy requirements (max. SME = 33.1 kWh/kg) and better rheological properties (max. Hyd = 69.2%, less intensive starch gelatinization with max. C3 = 1.47 Nm) than the L/D 16 version. The extruded wheat flour was characterized by improved hydration properties and limited retrogradation tendency, especially when hybrid extrusion with xylanase was applied. This may lead to favorable results, as the newly developed enzymatic extrusion modification method produces NSP-rich wheat flour with specific techno-functional and rheological characteristics that can be seen as a potential “clean label” enhancer in bakery products. Our statistical analysis confirmed feed moisture and screw speed to be the variables with the most significant effect on wheat flour features.

Optimization of Execution Microscopic Extrusion Parameter Characterizations for Color Polycarbonate Grading: General Trend and Box–Behnken Designs

This research article concentrates on process conditions in addition to improving color selections in polymer compounders and developing more accurate simulation models. The feed rate (FR), temperature (T) and screw speed (SS) are three processing variables that the research investigates using general trends (GTs) and Box–Behnken design (BBD) response surface methodology. The identical set of processing settings was tweaked at three separate phases independently of one another. This study uses the experimental design to investigate process parameters’ optimization while holding all other parameters constant. This design was given the name GT. To develop this design and its statistical optimization, this study used the software of the design expert method. A regression model was run in this design, which displayed collective as well as individual effects of the parameters on color images. The values of tri-stimulus color with the best optimization had the smallest proper color variance (dE*). To obtain information on pigment characteristics, an SEM image analysis was conducted, which aids in improving future designs and overcoming manufacturing issues that affect color fluctuation properties and waste reduction for various chemical grades, both of which enhance environmentally friendly processes.

Direct torque control for PMSM based on the RBFNN surrogate model of electromagnetic torque and stator flux linkage

Direct Torque Control (DTC) is widely used in motion control of motors. Classical DTC utilizes the Park transformation(dq-model) or observer to estimate the stator fluxlinkage and electromagnetic torque. However, the dq-model and observer lack descriptions of the cogging torque and magnetic saturation in permanent magnet synchronous motors (PMSM). This paper proposes a novel method based on the surrogate model to estimate stator fluxlinkage and torque for PMSM DTC. First, a finite element model (FEM) was established based on the parameters of PMSM. Using the FEM and Latin hypercube sampling (LHS), a surrogate model for estimating the stator fluxlinkage and torque of PMSM was constructed. The stator fluxlinkage and torque surrogate model, active flux observer, and dq current model under different control methods are constructed, respectively. The servo control parameters were tuned using the extended symmetric optimum algorithm, and simulation and experiments were conducted. Finally, electromechanical coupling models with a ball screw feed system were built based on various control and feedback methods. Simulation and experiment results indicate that the surrogate model reduces torque ripple, stator fluxlinkage offset, and feed system tracking error.

Research on axial nonlinear vibration characteristics of ball screw feed system considering segmented restoring force

Taking the ball screw feed system as the research object, the two degree of freedom axial dynamic model of the system is constructed firstly. Based on Hertz contact theory, when the ball screw pair adopts variable lead self-preloading to eliminate the assembly clearance between the ball and raceway, considering the nonlinear segmented axial elastic recovery force generated by the uneven contact deformation between the ball and raceway under the action of external excitation force, further derive the nonlinear dynamic equation group of the system. Next, the fourth-order Runge-Kutta method was used to numerically solve the equation system, obtaining the system’s two and three-dimensional phase diagrams, Poincaré sections, time-domain waveform diagrams, frequency spectra, and bifurcation diagrams. Then, the effects of damping constant, initial contact angle between ball and raceway in ball screw pairs, and number of balls on the system’s response characteristics were analyzed, and the influence of external excitation forces on system stability was further studied. Finally, it was verified through experiments that the axial vibration of the system is indeed nonlinear vibration, providing a theoretical basis for the study of the dynamic characteristics of the ball screw feed system.

Design and simulation of eco-friendly smartphone controlled forklift

The recent revolution in industrial technology increased the demand for unmanned forklifts that can be operated remotely. Unmanned forklifts eliminate the effort needed to train a highly qualified operator and reduce the accident rate due to driver fatigue. Currently, the operation of forklifts depends on either hydraulic systems or gasoline which has a negative impact on the environment. The increased awareness of the environmental threats urged the manufacturers to replace conventional forklifts with electrical ones. Unmanned electrical forklifts have a high cost that is considered a burden for developing countries, especially when being used in small warehouses. Thus, this paper presents an innovative approach for designing a semi-automated eco-friendly forklift suitable for small warehouses operated using a smartphone application. The forklift is designed to lift a maximum load of 200 N using a ball screw feed mechanism, characterized by its light weight and its ability to withstand corrosion. The structural stability of the forklift has been investigated using SolidWorks simulation. The designed model has been imported to MATLAB Simulink to estimate the suitable battery size required for forklifts’ operation in addition to calculating the total energy consumed during one complete work cycle. It is found that only 6.7 % of the energy is dissipated which promotes the energy-saving capabilities of the designed forklift.

High moisture extrusion of pea protein isolate to mimic chicken texture: Instrumental and sensory insights

High moisture extrusion processing (HMEP) is gaining attention in the plant-based food industry to obtain meat-like textures from different vegetal protein sources. The aim of this study was to evaluate the impact of extrusion process parameters (water feeding rate, barrel temperature and screw speed) on the texture and moisture content of high moisture extrudates (HME) from pea protein isolate using response surface methodology. Sensory textural profile of selected HME was compared with those of cooked chicken breast and a commercial extruded meat analogue sample. Extrusion process parameters had a significant effect on the characteristics of the final product. Barrel temperatures between 145 °C and 165 °C and a water feed rate between 53% and 57% produced HME with an instrumental texture similar to cooked chicken breast, 165 °C and 55% water feed being the conditions that produced the HME with the highest meat-like appearance and sensory fibrousness.

Performance Improvement of Flow Rate of Spiral Chip Feeder in Domestic Cattle Manure monitor Making Machine

The abstract outlines a study focused on the stability and effectiveness of a screw feeding mechanism designed for the outlet of pulping material in a screw reactor. This reactor functions as a continuous system where material is transported and mixed by a screw (augur). The study emphasizes the importance of operational conditions in influencing the process outcomes. To efficiently understand and optimize the system, the researchers employed modelling techniques, which are often quicker and more cost-effective than conducting experiments. The paper provides a comprehensive list of modelling approaches, both validated by experiments and theoretical, that is applicable to various aspects of screw reactor operation. Additionally, the study delves into new product development, specifically shaping a conical screw feeding reactor along with its shaft and flights design. A crucial aspect analyzed is the radial force effect on the flight surface during spiral rotation. Structural engineering techniques were employed to ensure the sustainability of the design, with validation results confirming its effectiveness. Keywords: Screw, Radial Force, Pulping Material

Dynamic vibration modeling of the ball screw feed system considering travel deviation

The vibration problem of the ball screw feed system in working conditions limits its application in precision machinery. However, few studies have developed models to investigate the vibration mechanism of the ball screw feed system in running status. In this paper, a dynamic model considering travel deviation and ball motion is proposed to explain the vibration mechanism of the ball screw feed system. This model is numerically solved and experimentally verified. Simulation results showed that, the travel deviation mainly affects the vibration amplitude rather than the frequency when the rotation speed is constant. Higher travel deviation introduces higher vibration amplitude, and the vibration of the feed system is more sensitive to the travel deviation of low frequency.