Side Rake Research Articles

Tool Geometry Influence on Surface Integrity of Machined Austenite Stainless Steel

The goal of this contribution was to describe the microstructure and properties changes of difficult to cut materials after turning. Surface residual stresses, roughness, microstructure of AISI 304 type stainless steel were studied as a function of side rake angle o. Residual stresses and phase composition of surface and sub-surface layers were determined using X-ray diffraction techniques. The presence of strain-induced martensite was investigated using Barkhausen noise, optical microscope, and microhardness measurement.

Investigation of Effects of Tool Geometry Parameters on Cutting Forces, Temperature and Tool Wear in Turning Using Finite Element Method and Taguchi’s Technique

Turning is one of the most widely metal cutting methods. Machines, tool geometry and machining parameters are the main factors influencing machining quality and efficiency. So there is a lot of research on it. This paper studies on the influence of the geometrical parameters of the tool including: back rake angle (BR), side rake angle (SR) and side cutting-edge angle (SCEA) on cutting forces, temperature and tool wear in turning using FEM (by Deform 3D finite element simulation software) and Taguchi’s technique (by Minitab16 statistical software) is used to design the experiment and to analyze output quality characteristics from simulation results. And the optimum tool geometry parameters are given.

On the Analytical Representation of Chip Area and Tool Geometry when Oblique Turning with Round Tools. Part 1: Chip Area Parameters Under Variation of Side and Back Rake Angle

Chip area parameters, such as undeformed chip thickness, equivalent chip thickness, contact edge length, etc., along with tool angles are among defining for the mechanical and thermal conditions of the cutting process. This paper considers the case of external turning with a round insert under variation, in wide range, of back and side rake angles and their influence on the main chip area and surface roughness parameters. Influence of other process variables, such as feed, depth-of-cut and nose radius, isalso studied. The developed analytical models and algorithms allow, not only to study the fundamental relationships, but to apply them in the design of new tools for conventional and rotary turning.

On the Analytical Representation of Chip Area and Tool Geometry when Oblique Turning with Round Tools. Part 2: Variation of Tool Geometry Along the Edge Line

This paper presents the models, analytical equations and results of analysis for determination of major cutting edge, orthogonal and normal clearance and rake angles, and cutting edge inclination angle. The analysis is carried for variable side and back rake angles used by the tool manufacturers and a corresponding variation of the geometry along the edge line for the case of round tools. The influence of tool nose radius, chamfer/chipbreaker angle and depth-of-cut was considered as well. Significant variation in orthogonal geometry from that stated in catalogues was found in most cases. The developed analytical solutions and algorithms allow the establishment of fundamental geometrical relationships and giving a correct prediction when developing new tools for conventional and rotary turning.

Improving Rate of Penetration for PDC Drill Bit Using Reverse Engineering

In petroleum industry, drilling is one of the most important aspects due to its economics. Reduction in drilling time is desired to minimize operations cost. This work focus on Polycrystalline Diamond Compact (PDC) drill bit which is categorized as a fixed cutter drilling bit. Problem such as wear and tear of PDC cutter are some of the main factors in drilling process failure affecting the rate of penetration (RoP). Thus, an intensive study in drill bit design could potentially save costs if the drill bit efficiency can be improved. The objective of this research is to improve the PDC cutter design and analyse design improvement in relation to the rate of penetration using reverse engineering (RE) approach. RE method is capable of resolving unavailable drill bit blueprint from the manufacturer due to propriety and confidential. RE non-contact data acquisition device, 3D laser scanner will be used to obtain cloud data of the existing worn drill bit. Computer Aided Design (CAD) software is used to convert cloud data of the PDC drill bit into 3D CAD model. Optimization of PDC Drill bit is focused on feature design such as back rake angle, side rake angle and number of cutters. CAE software is used to analyse the effect of the design feature modification to rate of penetration. Results show rate of penetration increases as the angle of both rake angle and number of cutter decreases.

Design of High-Efficient Bits for Igneous Rock in Xushen Gasfield

The igneous rocks in deep formations of the Xushen gasfield have the following characters: high abrasive property, high hardness, and high drillability, which lead to many drill bit accidents, few footage per bit , low efficiency of drilling, long drilling cycle, these severely restrict the exploration and development process of gas field. According to the features of deep formation, a hybird cutters bit is designed. It has three cones, with the overhang cone , duplicate taper and offset cone characters. The tungsten carbide cutters and the polycrystalline diamond compacts cutters are alternative collocation in the same tooth row in the bit. The exposed height of the tungsten carbide cutters is higher than polycrystalline diamond compacts cutters. The back rake angle of polycrystalline diamond compacts cutters is 10 ~ 40 °, the side rake angle is 10 ~ 30 °. The normal direction of working face stay the same with the composite slip direction, and the side rake pointed at adjacent gullet. Through the design method, it is integrated that the advantages of roller bit and PDC bit, the way of impact breakage and rotational shear breakage and the prominent performance of tungsten carbide cutters and polycrystalline diamond compacts cutters. It can improveROP and bit life.

3D numerical investigation of thermally assisted high efficiency ductile machining of nanocrystalline hydroxyapatite

This study investigates the effects of four different variables (initial workpiece temperature, side rake angle, edge radius/feed rate, and nose radius/depth of cut) on ductile regime machining of a bioceramic material known as nanohydroxyapatite (nano-HAP) using 3D numerical simulation. AdvantEdge FEM Version 5.9 is used to conduct turning simulations of the nano-HAP workpiece. Tecplot 360 is used to analyze the results of the simulations. Because the workpiece is thin, the entire workpiece is set to a uniform initial temperature to simulate laser preheating of the material. Initial workpiece temperature, rake angle (side rake angle), edge radius, and nose radius are varied, and the effects of these operating conditions on critical feed are investigated. It is found that critical feed increases as initial workpiece temperature increases, and also as negativity of rake angle increases. For the edge radius, it is concluded that an initial increase causes an increase in critical feed – however, at some value of edge radius, critical feed shows no further increase; for the nose radius, critical feed appears to show no significant dependence.

Studies on Insert-Type Gear Formed Milling Cutters

In roughing of large module gears, high efficient gear cutting with a formed milling cutter is noticed. In this case, the milling cutter is an insert type with both negative top rake and side rake angles. It is well known that negative rake angles increase cutting force and produce undesirable cutting surfaces. In this paper, a design method of insert-type gear formed milling cutters with both positive top rake and side rake angles is proposed. Firstly, the profile of cutting edge is calculated from the axial profile of the cutter by giving the design parameters such as the top rake angle, side rake angle and cutting edge angle, and the shape of insert pocket for the cutter body is designed by giving the thickness, length and width of the insert. However, these obtained design parameters are not always available because interference between the flank face and the work may occur. Therefore, a simulator that can interactively decide these design parameters was developed. Finally, the formed milling cutter were designed and made using the proposed method. Cutting tests using the trial-made milling cutter were carried out. As the results, the sufficient accuracy as the cutter in roughing of large module gears was obtained.

Experimental examination of the cooling performance of Ranque-Hilsch vortex tube on the cutting tool nose point of the turret lathe through infrared thermography method

In the present study, the cooling performance of the Ranque-Hilsch Vortex tube (RHVT) was experimentally investigated by infrared thermography (IRT) method. For this purpose, experiments were conducted on the cutting tool nose point of the lathe at different diameters, cutting speeds and cutting depths for cases in which cooling was not performed and RHTV cooling was performed. The sample material was gray cast iron in the form of round bars with 15 mm and 20 mm diameter respectively and 100 mm length. The inserts were manufactured by Sandvik Inc., with the ISO designation of TNMG 160404 MF (Triangular insert). The inserts were rigidly mounted on three different right hand style tool holders designated by ISO as MTJNR-L2020 K16T. In all instances, the side rake angle and back rake angle are 0° and fixed. The performance of RHVT was determined by using the temperatures obtained from thermal images (TIs). TIs were taken from the FLIR E45 infrared camera at 30 frames per second. When all the experimental results were evaluated together, the maximum performance of RHVT was found to be for a diameter of sample = 15 mm; cutting depth = 3 mm; cutting speed = 800 rpm (P 15,3,800).

Design and performance assessment for use in ultrasonic-aided cylindrical surface polishing

This paper studies the performance assessment of ultrasonic-aided electropolishing and ultrasonic-aided pulse-electropolishing of external cylindrical surfaces by three groups of design electrode recommended in a previous publication by the author. Six types of feeding electrode are connected with continuous direct current in an electropolishing experiment. It requires no expensive special-purpose equipment nor high material removal as does conventional electrochemical machining, it offers fast improvement of the surface roughness and reduces the residual stress on the workpiece in a new area in electropolishing. The control factors include die material, chemical composition and concentration of the electrolyte, electrolyte temperature, flowrate of the electrolyte, initial gap width, electrical current rating, workpiece and electrode rotational speed, and electrode feed rate. The experimental parameters are the frequency and power level of ultrasonics, the pulse period, and the electrode design. The design change from inner taper to inside pins for full-ring electrodes performs well. The designed flat arrowhead electrode with flute back rake angle and side rake angle comes out better than that of the double-flute arrowhead electrode. The disc electrode with pins attached on edge performs better than the disc with a discharge flute; and the polishing effect of disc-form electrodes is the best, followed by arrowhead electrodes, and ring-form electrodes. Using adequate electrode geometry as well as the ultrasonic aid, an effective and low-cost electropolishing of external cylindrical surface is presented.

Electropolishing of cylindrical workpiece of tool materials using disc-form electrodes

This research presents a new application of electropolishing using a low-cost disc-form electrode offering fast improvement of the surface roughness of SKD61. It requires no expensive special-purpose equipment or heavy material removal as conventional electrochemical machining does, and it also avoids the complex pre-polishing of the workpiece before the electropolishing. Round bars or round tubes produced by traditional turning, drawing, form rolling, or extrusion, can be successively electropolished using the designed disc-form electrodes. Five electrode designs are discussed. The experimental parameters include rotational speed of workpiece, electrical current rating and pulse period, electrode geometry, and electrode feed rate. Thinner disc and larger disc taper angle are associated with larger discharge space for the electrode, thus the polishing is more effective. A smaller end radius of the disc electrode produces higher current density and provides faster feed rate and a better polishing effect. A disc with discharge flute performs better, and larger flute back rake angle, side rake angle, wider flute, and deeper flute depth are also advantageous. Although the use of pulsed current slightly outperforms the fluted electrode using continuous current, it sacrifices both machining time and cost. The best electrode design is identified. A guideline for the design of electrodes is provided based on the experimental results.

An empirical survey on the influence of machining parameters on tool wear in diamond turning of large single-crystal silicon optics

We conducted a series of screening experiments to survey the influence of machining parameters on tool wear during ductile regime diamond turning of large single-crystal silicon optics. The machining parameters under investigation were depth-of-cut, feed rate, surface cutting speed, tool radius, tool rake angle and side rake angle, and cutting fluid. Using an experimental design technique, we selected twenty-two screening experiments. For each experiment we measured tool wear by tracing the tool edge with an air bearing linear variable differential transformer before and after cutting and recording the amount of tool edge recession. Using statistical tools, we determined the significance of each cutting parameter within the parameter space investigated. We found that track length, chip size, tool rake angle and surface cutting speed significantly affect tool wear, while cutting fluid and side rake angle do not significantly affect tool wear within the ranges tested. The track length, or machining distance, is the single most influential characteristic that causes tool wear. For a fixed part area, a decrease in track length corresponds to an increase in feed rate. Less tool wear occurred on experiments with negative rake angle tools, larger chip sizes and higher surface velocities. The next step in this research is to perform more experiments in this region to develop a predictive model that can be used to select cutting parameters that minimize tool wear.

PM—Power and Machinery: Optimizing Design Parameters of a Mouldboard Plough

Owing to the complexity in designing a mouldboard plough, it has been manufactured mostly based on experience and empirical methods. In this research, a mathematical model of a mouldboard plough has been developed to design it for the minimum amount of operating energy. Using this model, a mouldboard plough requiring the least specific draught was designed for given soil conditions (specific weight of soil, cohesion, soil–metal adhesion, soil–metal frictional angle and soil internal frictional angle) and operating conditions (speed and depth of cut) for a given power availability. Five parameters were set to describe a mouldboard plough, namely width of cut, share angle, side rake angle, angular acceleration of soil inversion in the transverse plane and length of plough in the direction of travel.The designed plough and a commercial mouldboard plough were tested in two different soils in a laboratory soil bin to validate the model and to compare performance. Specific draught requirements were compared and it was found that the difference between predicted and measured specific draught was not significant. The new plough, however, needed significantly less specific draught than the commercial plough at identical operating conditions.

ＡＺ９１マグネシウム合金鋳物の正面切削性

Facing machinability tests were performed on the magnesium alloy castings AZ91 by measuring cutting resistance, shear angle, surface roughness and chip forming. Face cutting done from periphery to center of specimen with cemented carbide alloy K20 in which has various side rake angle. Regardless of the different side rake angles, both cutting forces and machined surface of the alloy were independent of cutting speed. The cutting resistances increased with increasing both feed rate and depth of cut, and decreased with increasing of side rake angle. The feed rate influenced a little to the machined surface, and it was superior to that of theoretical valves on the basis of feed marks and tool configuration. The orderly feed marks were observed on the machined surface, however, in the case of both high feed and large side rake angle, the burr and tear were observed on the machined surface. The size of the chips decreased with decreasing cutting speed and increasing feed rate. The thickness of the chips at start of cutting became thinner than that at end. The cutting ratio showed large value at the outer part of specimen under high cutting speed. The shear angle decreased with decreasing cutting speed. The AZ91 magnesium alloy castings had excellent facing machinability in high speed heavy cutting. The facing machinability of AZ91 magnesium alloy castings was excellent and exhibited good performance in high speed heavy cutting.

ＳｉＣｐ／Ａ３８３アルミニウム合金複合材料の旋削被削性

Turning machinability test were performed on the SiCp/A383 aluminum alloy composite by measuring tool wear, cutting resistance and surface roughness. Shapes of flank wear were changed from band type to triangle type with increase of flank wear. The flank wear were increased with increasing of both cutting speed and cutting distance. The flank wear of the first stage of cutting was very large regardless cutting conditions. It was more than 0.2 mm on cutting distance of 50 mm. Regardless side rake angle, cutting resistance were increased with increasing of both cutting speed and cutting distance. In case of cutting speed on 1.67 m/s, finished surface roughness in the first stage of cutting was large, but finished surface roughness was changed for better with increasing of cutting distance. In case of start of cutting on cutting speed of more than 3.33 m/s, the finished surface roughness become better increased with increase of cutting distance. However finished surface roughness suddenly increased with increase of tool wear.

Optimization of Animal Drawn Tillage Implements: Part I, Performance of a Curved Tillage Implement

The effects of design and operational parameters such as speed, tail angle, side rake angle and radius of curvature of a curved soil tillage implement on horizontal and vertical forces have been investigated under laboratory conditions. Seven different wings of different radii of curvature (150, 200, 250, 300, 350, 400 and 450mm) were designed. To minimize the effect of physical size, all the curves were made to have equal dimensions before bending them to the required curvature. The ranges of tail angle, side angle and speed used for the investigation were 32° to 54°, 40° to 65° and 0·5 m/s to 2 m/s respectively. The effect of radius on the horizontal force was different for different tail angles used. However, no great effect of radius on the horizontal force was observed. A radius of about 270 mm was found to be optimum for a curved implement. For the vertical force (directed downward), it was observed that, for all tail angles used, the force increased with decreasing radius. A considerable effect of tail angle on both horizontal and vertical forces was observed. Both the horizontal and the vertical forces increased with an increase of tail angle. Experimental investigation showed that both speed and radius affect the relation between side rake angle and force. Equations have been developed to predict the forces that result during interaction of a curved implement with soil and attempts made to fit these equations to the experimental data.

工業用純チタンの被切削性に及ぼすＫ種超硬工具の影響

Sintered WC tools are known to be effective and economical cutting tool for titanium alloy. Carbide tools with various grain size, content of WC and side rake angle were tested to evaluate the cutting performance-tool wear, cutting force and finished surface-in machining of commercial pure titanium. The wear resistance of the tools changes with the grain size of WC, in such a way that the tool with 1μm WC grain is the best. The wear of the tool with 94wt% WC is the smallest among the composition range of WC between 93 and 97wt% under the grain diameter of WC fixed to about 1μm. The tool wear progresses slowly and the level of cutting force is low for the tools with pressed chip breaker, regardless of WC content. An excellent cutting performance is found to be obtainable with the tool which has a side rake angle between -π/39 and π/36 rad.

マグネシウム合金鋳物ＭＣ２の旋削被削性に及ぼす工具横すくい角の影響

Turning machinability tests were performed on the magnesium alloy castings MC2 by measuring the cutting resistance, the cutting ratio, the shear angle, the surface roughness and the chip formation. Regardless of the side rake angle, both the tangential and the traversing force of the alloy were independent of the cutting speed, and were affected remarkably by increasing the feed. The tangential force decreased with increasing the side rake angle. The traversing force showed a negative value with acceleration of the feed using the side rake angle of 30°bit. Both the cutting ratio and the shear angle increased with acceleration of the cutting speed and the feed, and 0.54 to 0.82 as the cutting ratio and 30.2°to 44.6°as the shear angle. The machined surface finishing showed smoother with increasing the cutting speed and decreasing the feed, and was superior or nearly to that calculated theoretically. Both the large and small spiral coil type chips were easily treatable. There was no trouble in the flaming during cutting. The MC2 alloy had excellent machinability in the high speed heavy cutting.

PDC Drill Bit Design and Field Application Evolution

This paper traces the development of polycrystalline diamond compact (PDC) bits from their introduction in 1973. Such design features as body materials, crown profiles, cutter density, and cutter exposure and their effect on bit performance are discussed. In addition, the paper reviews various aspects of bit applications engineering, including bit hydraulics, drilling fluids, directional behavior, and formation types.

Evolution of Polycrystalline Diamond Compact Bit Designs for Rocky Mountain Drilling

The Rocky Mountain region of the U.S. has proved to be a good area for polycrystalline diamond compact (PDC) bits in selected formations. Lower costs per foot as a result of higher penetration rates and longer bit lives have been realized in many applications. PDC bits are used routinely in Wyoming in the Green River and Powder River basins. Simply using a PDC bit in these areas does not necessarily ensure an economical run. Care must be taken in choosing the correct bit design for each application to obtain the lowest cost per foot. Since the first PDC bit run, there has been an evolution of designs to enhance penetration rates, and thus to lower drilling cost per foot. This evolution has included changes in bit profile, cutter density, cutter exposure, cutter side rake, and cutter shape. When optimally combined, these features have increased penetration rates by well over 100% in many formations.