Optimization of High-Precision Reaming Holes with Small Diameters

2013 ◽  
Vol 10 (2) ◽  
pp. 18-21
Author(s):  
Stanislav Fiala ◽  
Karel Kouřil ◽  
Marek Pagáč
Keyword(s):  
Cutting Speed ◽  
Small Diameter ◽  
Operational Reliability ◽  
High Productivity ◽  
High Cutting Speed ◽  
Reduced Costs ◽  
Body Components ◽  
Process Fluid ◽  
Cutting Point ◽  
Cutting Speeds

Abstract In many applications, it is at the final machining precision holes, very advantageous to use a reamer whose cutting portion is made of a cermet, but also other performance materials (PCD, CBN). In these modern tools can be compared with the instruments of conventional cemented carbides apply significantly higher cutting speeds at longer blade life cutting edges. Specific problems and significant demands on the tech-nical design and implementation of these instruments arise from their use for reaming holes with small diameters. Especially in cases where it is required to have high productivity, a high cutting speed and feed. Especially for small diameter tools it is extre-mely difficult to supply the necessary amount of process fluid to the cutting point in real time. A sufficient quantity of liquid will not only provide cooling but also chip. The requirement is to achieve high operational reliability as well as reduced costs using intensive cutting conditions. This situation helps to solve the present structural design of composite reaming tools. Specifically, the optimization of the reamer for reaming holes ø 4,2 H8 with a depth of 8 mm in body components for the automotive industry .

The Effect of Cutting Speed on Chip Formation Under Orthogonal Machining

1985 ◽  
Vol 107 (1) ◽  
pp. 55-63 ◽  
Author(s):  
D. Lee
Keyword(s):  
Chip Formation ◽  
Cutting Speed ◽  
Chip Morphology ◽  
High Cutting Speed ◽  
Orthogonal Machining ◽  
Localized Heating ◽  
On Chip ◽  
All Speeds ◽  
Cutting Speeds ◽  
Steel Chip

Orthogonal machining experiments were conducted at different cutting speeds ranging from 8.5 × 10−2 cm/s (0.17 ft/min) to about 2.5 × 102 cm/s (492.1 ft/min) with 6061-T6 aluminum, 4340 steel, and Ti-6A1-4V titanium to examine the chip formation process. The most pronounced effect of the cutting speed on chip morphology was observed with the titanium alloy; the chips remained segmented at all speeds, but became continuous macroscopically at high cutting speeds. The steel chip also became continuous and oxidized, showing the effect of localized heating. The changing chip morphology that is accompanied with decreasing normal force at the high cutting speed is rationalized on the basis of localized adiabatic heating, which is dependent on the thermal-mechanical properties of each material.

scholarly journals Experimental investigation of the effects of cryogenic cooling on tool life in Ti6Al4V milling

2021 ◽  
Author(s):  
Paolo Albertelli ◽  
Valerio Mussi ◽  
Matteo Strano ◽  
Michele Monno
Keyword(s):  
Tool Life ◽  
Cutting Speed ◽  
Cryogenic Cooling ◽  
Model Parameters ◽  
Cryogenic Milling ◽  
High Cutting Speed ◽  
Cutting Velocity ◽  
Life Tests ◽  
Conventional Cooling ◽  
Cutting Speeds

AbstractIn this paper, the results of an experimental campaign of cryogenic milling are presented and discussed. For this purpose, a specific experimental setup that allowed to feed the liquid nitrogen LN through the tool nozzles was used. Tool life tests were carried out at different cutting speeds. The tool duration data were collected and used to identify the parameters of the Taylor’s model. Different end-of-life criteria for the tool inserts were even investigated. The achieved results are compared to those obtained using conventional cooling. It was observed that at low cutting velocity, conventional cooling still assures longer tool lives than in cryogenic condition. Since in cryogenic milling the increasing of the cutting velocity is not so detrimental as in conventional cutting, at high cutting speed (from 125 m/min) longer tool durations can be achieved. Statistical analyses on the model parameters were carried out to confirm the presented findings. The analysis of the effect of the cooling approach on the main wear mechanisms was also reported. At low cutting speed, adhesion and chipping phenomena affected the tool duration mainly in cryogenic milling.

Tool Life of Coated Tools in Face Milling of GH4169 at Various Cutting Speeds

2013 ◽  
Vol 770 ◽  
pp. 126-129 ◽  
Author(s):  
Xiang Yu Wang ◽  
Chuan Zhen Huang ◽  
Bin Zou ◽  
Qing Ge Zhang ◽  
Han Lian Liu ◽  
...  
Keyword(s):  
Tool Life ◽  
Flank Wear ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Face Milling ◽  
High Cutting Speed ◽  
Coated Tools ◽  
Life Tests ◽  
Material Tool ◽  
Cutting Speeds

GH4169 is widely used in aerospace industry, and it is a typical difficult-to-cut material. Tool life in cutting GH4169 is very low. In this paper, tool life tests of face milling GH4169 were carried out at 30~90m/min with coated tools. The effects of cutting speed and feed rate on the tool life were studied. It was found that the tool life was very sensitive to the cutting speed. And tool failure mode was flank wear at low cutting speed, but turned to tipping at high cutting speed. At last, the suitable cutting parameters were recommended.

Cutting Performance and Wear Mechanism of Si3N4-Based Nanocomposite Ceramic Tool

2010 ◽  
Vol 443 ◽  
pp. 324-329 ◽  
Author(s):  
Bin Zou ◽  
Chuan Zhen Huang ◽  
Han Lian Liu ◽  
Jin Peng Song
Keyword(s):  
Wear Resistance ◽  
Wear Mechanism ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Performance ◽  
Nano Particles ◽  
Ceramic Tool ◽  
Tool Materials ◽  
High Cutting Speed ◽  
The Matrix

Si3N4/TiN nanocomposite tool and Si3N4/Ti(C7N3) nanocomposite tool were prepared. The cutting performance and wear mechanism of Si3N4-based nanocomposite ceramic tool was investigated by comparison with a commercial sialon ceramic tool in machining of 45 steel. Si3N4-based nanocomposite ceramic tool exhibits the better wear resistance than sialon at the relatively high cutting speed. The increased cutting performance of Si3N4-based nanocomposite ceramic tool is ascribed to the higher mechanical properties. Nano-particles can refine the matrix grains and improve the bonding strength among the matrix grains of Si3N4-based nanocomposite ceramic tool materials. It contributes to an improved wear resistance of the cutting tools during machining.

Mechanism of Variable Helix Tools in Suppressing Chatter Using Process Damping for Machining Titanium Alloys at Low Cutting Speed

2013 ◽  
Vol 773-774 ◽  
pp. 370-376
Author(s):  
Muhammad Adib Shaharun ◽  
Ahmad Razlan Yusoff ◽  
Mohammad S. Reza
Keyword(s):  
Titanium Alloy ◽  
Cutting Speed ◽  
Milling Process ◽  
Cutting Process ◽  
Chatter Vibration ◽  
Process Damping ◽  
High Cutting Speed ◽  
Titanium Machining ◽  
Different Types ◽  
Variable Helix

Titanium is difficult-to-cut materials due to its poor machinability and thermal conductivity when machining at high cutting speed. To overcome this machining titanium alloy problem, this study in interaction between machining structural system and the cutting process are very important. One of the main problems in the cutting process is chatter vibration. Due to chatter problem, the mechanism to suppress chatter named, process damping is a useful method can be manipulated to improve the limited productivity of titanium machining at low speed machining in milling process. In the present study, experiment are conducted to evaluate and study the process damping mechanism in milling using different types of variable tools geometries. These tools are variable he-lix/uniform pitch, variable pitch/uniform helix and variable helix and pitch and uniform helix/pitch. The result showed that the variable helix and pitch tools is very significantly improve process damping performance in machining titanium alloy compare to traditional of regular tools and other irregular tools.

Deep Hole Machining with a Small Diameter Drill and Ultrasonic Vibration

2017 ◽  
Vol 749 ◽  
pp. 107-110
Author(s):  
Yuta Masu ◽  
Tomohito Fukao ◽  
Taiga Yasuki ◽  
Masahiro Hagino ◽  
Takashi Inoue
Keyword(s):  
Surface Roughness ◽  
Ultrasonic Vibration ◽  
Cutting Tool ◽  
Cutting Speed ◽  
Small Diameter ◽  
Maximum Amplitude ◽  
Depth Of Cut ◽  
Deep Hole ◽  
Work Material ◽  
Finished Surface

The method of imparting ultrasonic vibration to the cutting tool is known to improve the shape accuracy and finished surface roughness. However, a uniform evaluation of this function in drilling has not been achieved, and the cutting process cannot be checked from the outside. The aim of this study is to investigate the cutting characteristics in deep hole drilling when an ultrasonic vibrator on the table of a machining center provides vibration with a frequency of 20 kHz to the work piece. The ultrasonic vibrations in this system reach the maximum amplitude in the center of the work material. We evaluated the change in finished surface roughness between the section where drilling starts to the point of maximum amplitude with ultrasonic vibration. The main cutting conditions are as follows: cutting speed (V) 12.6 (mm/min); feed rate (s) 30, 60 (mm/rev); depth of cut (t) = 32 (mm); work material, tool steel; cutting tool material, HSS; point angle (σ) 118 (°); and drill diameter (φ) 4 (mm). Lubricant powder was also added to clarify the cutting effect, and compared the condition in which there was no ultrasonic vibration. The results showed that surface roughness at the point of maximum amplitude was better than that with no vibration.

Subsea Cable Stability on Rocky Seabeds: Comparison of Field Observations Against Conventional and Novel Design Methods

2018 ◽  
Author(s):  
Terry Griffiths ◽  
Scott Draper ◽  
Liang Cheng ◽  
Feifei Tong ◽  
Antonino Fogliani ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Power Transmission ◽  
Small Diameter ◽  
Oil And Gas Industry ◽  
Operational Reliability ◽  
Design Methods ◽  
Gas Industry ◽  
Integrity Management ◽  
Tidal Stream ◽  
Almost All

As offshore renewable energy projects progress from concept demonstration to commercial-scale developments there is a need for improved approaches beyond conventional cable engineering design methods that have evolved from larger diameter pipelines for the oil and gas industry. New approaches are needed to capture the relevant physics for small diameter cables on rocky seabeds to reduce the costs and risks of power transmission and increase operational reliability. This paper reports on subsea cables that MeyGen installed for Phase 1a of the Pentland Firth Inner Sound tidal stream energy project. These cables are located on rocky seabeds in an area where severe metocean conditions occur. ROV field observation of these cables shows them to be stable on the seabed with little or no movement occurring over almost all of the cable routes, despite conventional engineering methods predicting significant dynamic movement. We cite recent research undertaken by the University of Western Australia (UWA) to more accurately assess the hydrodynamic forces and geotechnical interaction of cables on rocky seabeds. We quantify the conformity between the cables and the undulating rocky seabed, and the distributions of cable-seabed contact and spanning via simulations of the centimetric-scale seabed bathymetry. This analysis leads to calculated profiles of lift, drag and seabed friction along the cable, which show that all of these load and reaction components are modelled in an over-conservative way by conventional pipeline engineering techniques. Overall, our analysis highlights that current cable stability design can be unnecessarily conservative on rocky seabeds. Our work foreshadows a new design approach that offers more efficient cable design to reduce project capex and enhance through-life integrity management.

Investigation of Temperature and Stress Distribution on High Speed Machining of Ti6Al4V and 316L Steel Biomaterials Using Explicit Dynamic Analysis

2017 ◽  
Vol 889 ◽  
pp. 84-89
Author(s):  
Pandithevan Ponnusamy ◽  
Mullapudi Joshi
Keyword(s):  
Dynamic Analysis ◽  
Mechanical Behaviour ◽  
High Speed ◽  
Cutting Speed ◽  
Surgical Instruments ◽  
Interface Temperature ◽  
High Speed Machining ◽  
316L Steel ◽  
Explicit Dynamic ◽  
Cutting Speeds

In high speed machining, to dynamically control the mechanical behaviour of the materials, it is essential to control temperature, stress and strain by appropriate speed, feed and depth of cut. In the present work, to predict the mechanical behaviour of Ti6Al4V and 316L steel bio-materials an explicit dynamic analysis with different cutting speeds was carried out. Orthogonal cutting of 316L steel and Ti6Al4V materials with 720 m/min, 900 m/min and 1200 m/min cutting speeds was performed, and the distribution of stress and temperature was investigated using Jonson-Cook material model. Additionally, the work aimed at determining the effect of cutting speed on work piece temperature, when cutting is carried out continuously. From the investigation, it was found that, while machining Ti6Al4V material, for the increase in cutting speed there was increase in tool-chip interface temperature. Specifically, this could found till the cutting speed 900 m/min. But, there was a decrease in tool-chip interface temperature for the increase in speed from 900 m/min to 1200 m/min. Similarly for 316L steel, the tool-chip interface temperature increased when increasing the cutting speed till 900 m/min. But reduction in temperature from 650 °C to 500 °C for steel and 1028 °C to 990 °C for Ti6Al4V were found, when the cutting speed increased from 900 m/min to 1200 m/min. The study can be used to conclude, at what temperature range the adoption of material with controlled shape and geometry is possible for potential applications like, prosthetic design and surgical instruments prior to fabrications.

Cutting Experiments in Cutting Speeds of up to 200 m/s with a High-Speed Impact Cutting Tester

2012 ◽  
Vol 523-524 ◽  
pp. 1041-1046 ◽  
Author(s):  
Tappei Higashi ◽  
Masato Sando ◽  
Jun Shinozuka
Keyword(s):  
High Speed ◽  
Ambient Pressure ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
High Speed Impact ◽  
Air Gun ◽  
Impact Cutting ◽  
Compressed Gas ◽  
Cutting Experiments ◽  
Cutting Speeds

High-speed orthogonal cutting experiments with cutting speeds of up to 200 m/s with a high-speed impact cutting tester of air-gun type are attempted. In this tester, a light projectile with a small built-in cutting tool is loaded into a tube, being accelerated by a compressed gas. The projectile captures the chip that is indispensable to analyze the cutting mechanism. The projectile holding the chip is decelerated by another compressed gas just after finishing the cutting, being stopped without damage in the tube. Successful experiment can be accomplished by setting adequate values of the operation parameters for the experiment, which are the pressure of each gas and the opening and shutting time of the solenoid-controlled valve for each compressed gas. In order to determine the adequate values of these parameters, a ballistic simulator that simulates the velocity and position of the projectile traveling in the tube is developed. By setting the values of these parameters obtained by the simulator, the cutting speed of 200 m/s is achieved when the ambient pressure is set to be a vacuum and helium is used for each compressed gas. This paper describes the ballistic simulator developed and shows the experimental results of the high-speed cutting of aluminum alloy A2017.

Study of a High Performance AFM Probe-Based Microscribing Process

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Keith Bourne ◽  
Shiv G. Kapoor ◽  
Richard E. DeVor
Keyword(s):  
Tool Wear ◽  
High Performance ◽  
Cutting Speed ◽  
Rake Angle ◽  
Motion Platform ◽  
High Cutting Speed ◽  
Working Volume ◽  
Afm Probe ◽  
Tool Motion ◽  
Five Axis

In this paper, a mechanical microscribing process is described that combines AFM probe-based microscribing with a five-axis microscale machine tool motion platform in order to achieve high scribing speeds, a large working volume, and the capability of cutting curvilinear patterns of grooves. An experiment is described that demonstrates groove formation, groove shape, and tool wear when long grooves are formed using multiple tool passes. A second more systematic experiment is described in which short-distance single-pass cutting tests were used to explore the effects of cutting speed, nominal tool load, and AFM probe mounting angle on groove geometry, tool wear, effective rake angle, and chip formation. Lastly, an experiment is described in which a long curvilinear groove is cut. It is shown that the most well-formed grooves were cut and acceptable tool wear was achieved, when using a high cutting speed, high nominal tool load, and low probe mounting angle. The capability of cutting grooves as long at 82 mm but with depths of only a few hundred nanometers, using a single tool pass at cutting speeds as high at 25 mm/min is demonstrated.

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