Rotary Feed Research Articles

Desired Compensation Adaptive Robust Control for NC Rotary Table Direct Drive Rotary Feeding System

For the characteristics of direct drive NC rotary table servo system using ring permanent magnet torque motor being influenced by varying of external disturbance, parameters varieties and load disturbances, the desired compensation adaptive robust position controller based on projection algorithm is designed to achieve high performance and parameters estimation. The desired compensation adaptation law based on projection algorithm for uncertainties off-line estimation is calculated by desired information only to achieve high requirement of the servo system of the ring permanent magnet torque motor. Compared with adaptive robust controller, the controller can reduce the effect of measurement noises. Therefore the process of uncertainties estimation is faster and the estimators are more accurate. Simulation result shows that the designed method enables the system to be better in robustness in general.

Focus on vacuum and cryogenics

Focus on vacuum and cryogenics

Application of Taguchi and Response Surface Methodologies for Surface Roughness in Rotary Tool Polishing Hardness Mould Steels

This research proposes a new application of 3-axis CNC milling machine for polishing the 60 HRC hardness steels. The rotary polishing tools are designed by refer to the end-mill ball nose’s design. The diamond powder are coated in rotary polishing tools by resinoid bonding method and concentrated in 4.4 karat/cm2. The Zig-milling tool paths are used to polish the hardness steel. After polishing, the confocal laser scanning microscope is used to analyze the arithmetic mean surface roughness of the hardness steels. The L12 orthogonal array of the Taguchi’s method is selected to conduct the matrix experiment to determine the optimal polishing process parameters. The diamond grit size and cutting speed of the rotary polishing tools, feed rate and step over of the tool path, the depth of polishing process penetration, and polishing time are used to study. The combination of the optimal level for each factor of the hardness steel polishing process are used to study again in the confirmation experiment. The predicted signal to noise ratio of smaller - the better under optimal condition are calculated by using the data from the experiment. The combination of the optimal level for each factor are used to study again in the confirmation experiment and the result show that polishing time was a dominant parameter for the surface roughness and the next was depth of penetration. The response surface design is then used to build the relationship between the input parameters and output responses. The experimental results show that the integrated approach does indeed find the optimal parameters that result in very good output responses in the rotary polishing tools polished hardness mould steel using CNC milling machine. The mean surface roughness of hardness steel polishing process is improved by the diamond rotary tools with the 3-axis CNC milling machine.

Development of Table-on-Table-Type Five-Axis Machining Center: New Structure and Basic Characteristics

The demand for five-axis machining centers has been increasing rapidly, as companies seek “intensive processes” and “high accuracy.” However, it is generally more difficult for five-axis machining centers to achieve the same or higher accuracy than three-axis machining centers since it is necessary to have two more rotary feed axes besides the three linear feed ones. Many kinds of five-axis machining centers with various structures have been developed to date; an analysis of the advantages and disadvantages of major five-axis machining center structures was done first. As a result of this analysis, this paper focuses on the “table-on-table type” five-axis machining center. It is capable of accuracy because of its wide range of rotation for the rotary axis and its advantages in the adjustment process of the axis. and this paper proposes a five-axis machining center which has this construction. Furthermore, a new high-speed, highaccuracy, “table-on-table type” of five-axis machining center which uses a direct-drive motor for the rotary axis and a driven center of gravity for the linear axis has been developed based on this concept, and its accuracy has been verified.

Prediction Model for Rotary Kiln Coal Feed Based on Hybrid SVM

A SVM (Support Vector Machine) classification for rotary kiln based on time series trend characteristics was presented in this paper. The amount of coal feed depended on its trends which were predicted by the dynamic rules of rotary kiln data. The original sample was cleaned by data preprocessing, and the piecewise linear representation based on key points was used to extract the trend characteristics of rotary kiln time series data. The parameters of SVM were decided by Particle Swarm Optimization method. It was proved that the proposed model with high prediction level which enhanced the robustness of the control of rotary kiln could be applied on the actual situation.

Design and Characterization of an Improved Screw-Assisted Rotary Feeding System for Aerosolization of Ultra-Small Quantities of Particulate Solids

Many previous studies have examined solid-state particle discharge systems. However, several drawbacks have been encountered in terms of laboratory-scale particle feeding systems (e.g., high feeding rates, discontinuous feeding characteristics, the absence of long-term stability, and the use of high carrier gas volume rates). In this study, a state-of-the-art screw-assisted rotary feeding system was developed and evaluated in terms of aerosolization characteristics such as particle number concentration, geometric mean diameter, and geometric standard deviation. The various experimental conditions included changes in the rotational speed of the rotor, changes in the number of rotor grooves, and the existence or nonexistence of screw operation. Calcium carbonate (CaCO 3 ) powder was selected as the discharged sorbent particle. To verify the performance of the designed feeding system, we measured number concentrations with and without operation of the screw. Uniformity (i.e., the steadiness of feeding charac...

Manufacturing models for the design and NC grinding of a revolving tool with a circular arc generatrix

This paper presents a systematic method for the design and manufacturing of a revolving tool with a circular arc generatrix. The mathematical models of a helical flute and cutting-edge curve for this special shaped revolving tool are presented. The geometry of the flute grinding wheel can be obtained from the solution of the inverse envelope problem for a given flute profile on the waist part (maximum sectional radius) of this tool. The equations for axial, radial and rotary feeding velocity of the workpiece in the flute NC grinding process are also derived. In addition, the deviation of cutting-edge curve, residual material and the land lack caused by the modified radial feeding velocity, are taken into consideration. In order to finish the residual material and to rebuild the land of the cutter, a technique for compensation has been developed in this research.

Life Models for Small-Diameter Polycrystalline Diamond Compact Bits in Hard Abrasive Media

Mathematical models for bit life of polycrystalline diamond compact (PDC) drill bits were developed for drilling small holes in hard abrasive media. Based on the wear-out criterion of an average 0.060 in. (1.5 mm) flank wear land, bit life equations were formulated in three forms: bit life versus rotary speed and feed rate, bit life versus rotary speed and penetration rate, and wear rate versus cutting speed and cutter engagement area. The traditional linear-logarithmic model proved inadequate to describe bit life, whereas the quadratic-logarithmic model provided the best bit life prediction equation. Consequently, it would be possible to predict the optimum economical drilling conditions more accurately by employing a quadratic-logarithmic based bit life equation. The equation demonstrated the ability to predict the bit life precisely under different modes of wear.

Wear Characteristics of Polycrystalline Diamond Compact Drill Bits in Small Diameter Rock Drilling

The wear characteristics of polycrystalline diamond compact (PDC) drill bits were investigated in the context of drilling small holes in a hard abrasive medium. An efficient method for measuring wear of the PDC drill bits was developed. The wear test results were grouped or categorized in terms of rotary speed, feed and wear or failure characteristics. Contrary to the three classical wear phases (break-in, uniform wear and rapid breakdown) of the single material cutters, four distinctive wear phases were formed for the PDC cutters: I–break-in, II–diamond wear, III–carbide wear, and IV–rapid breakdown. The characteristics of the wear phases were identified and some suggestions were made to alleviate the wear problem.

4352530 Rotary feed for tonographic scanning apparatus

Unreinforced Al-20Si-3Cu-1Mg (ASCM) aluminium alloy and SiC particle reinforced Al-20Si-3Cu-1Mg (ASCM-SiC) aluminium matrix composites were fabricated by powder metallurgy (PM). The samples were slid against 4Cr13 stainless steel in a reciprocal friction tester under a load of 25 N to 175 N and sliding velocity of 0.3 to 1.2 m s−1 at ambient conditions. The results show that SiC particulate-reinforced aluminium matrix composites possess good wear resistance at dry sliding and less wear resistance under water lubrication. Ploughing wear is the dominant wear mechanism at dry sliding and tribochemical wear is dominant under water lubrication. SEM, AES and XPS were used to examine the wear morphology and surface chemistry.

Hybrid integrated circuit manufacturing process as controlled by shop information systems: Dennis L. Krause and Douglas A. Locy. IEEE Trans. Components, Hybrids Mfng Technol.CHMT-3 (3), 345 (September 1980)

Pneumatic rotary feed spreaders represent essential equipment in the feeding system of present day industrial-scale sea cage aquaculture. This study presents experimentally obtained attitude measurements and corresponding surface distribution patterns of pellets in order to characterize the dynamic behavior and performance of such spreaders. Spreader attitude and direction were measured by employing an attitude and heading reference system along with a rotary encoder. In addition, an unmanned aerial vehicle (UAV) was used to record pellet surface impacts from the air, and the position and direction of the spreader was obtained by applying computer vision methods to the recorded video. The proposed UAV method was fast to deploy, requires minimal equipment installation and presents a viable alternative to the approach of collecting pellets manually using Styrofoam boxes as reported in earlier studies. The findings from this study may be used as a base for further development and refinement with respect to using an UAV to observe the performance and spatial pellet distribution from various feed spreaders used in aquaculture. Such a tool may be valuable for farmers and equipment producers which may easily evaluate the performance of various spreader designs. In addition, the results serve as valuable input for parametrization and validation of mathematical feed spreader models.