Machine Cutter Research Articles

Optimal control of a novel cutter head driving system for tunnel boring machine

The cutter head of a tunnel boring machine may be trapped in extremely adverse geological environments, which requires a large enough driving torque to get rid of the trapped condition. In this paper, a novel driving scheme is proposed to improve the driving performance of the tunnel boring machine cutter head without increasing the installation power. First, the hydro-viscous clutch is introduced to achieve the soft start of the cutter head by the flexible effect of viscous oil film. Then, the flywheel is employed as the energy storage element to provide sufficient torque during the hydro-viscous clutch engagement, which assists the cutter head to get rid of the trapped condition. Moreover, an optimal state feedback control law based on a linear quadratic regulator is designed by compromising system impact and hydro-viscous clutch friction loss to optimize the hydro-viscous clutch engagement process and achieve favorable driving performance of the cutter head. Finally, numerical simulations are conducted to validate the effectiveness of the proposed driving technology.

REVIEW ON COCONUT DEHUSKING AND CUTTING MACHINE

REVIEW ON COCONUT DEHUSKING AND CUTTING MACHINE

Determination of White Layer Characterstics on Machining Process

Now a day’s industries requirement as light weight and high wear resistance component. The component used as a various industrial application areas. The material also high self lubricant material also need. In this work we was used aluminium matrix composite with added in a CNT as a Nano materials. The materials has used to a high wear resistance and it is act as a self lubricant material also the material carry out different percentage and casting used in a stir casting method. The casting sample cut by a testing sample by used in an EDM wire cut machine. The sample carried out the result and plots the graphs. And the samples are carry out wear test using pin on disc method. The result shown in graph. And the sample machining study also did by EDM Wire cut machine. Finally carry out the white layer of the material. The study discussed with the paper. In this research work used in a light weight and self lubricant material needed area

Cutting Characteristics and Layout of Pre-cutting Machine Cutter

The pre-cutting machine is becoming valued due to its ability to effectively prevent surface settlement and reduce vibration in tunnel construction. To obtain the cutting characteristics and layout of pre-cutting machine cutter, the cutting tests by the pre-cutting machine cutter are conducted and the cutting laws are also studied. The research results show that the cutting force rather than normal force and side force is responsible for the rock breaking. With the increase of the cutting depth and cutting spacing, the cutting forces increase generally. But for the little value of cutting spacing, the cutting force can not increase continuously when the cutting depth increase to a relatively large value. Furthermore, for a given cutting depth, the cutting force will keep at an approximate constant rather than continuous increase with the increase of the cutting spacing when the cutting spacing increases to a relatively large value. The specific energy decreases nonlinearly with the increase of cutting depth and the decrease of specific energy is not significant when the cutting depth is more than 12 mm. Moreover, there exists an optimal cutting spacing for a given cutting depth. To maintain a desirable cutting efficiency, the ratio of cutting spacing to cutting depth should be controlled between 1 and 2. Finally, the layout plan of the pre-cutting machine cutter is proposed based on the research results and is applied in the actual manufacturing of the pre-cutting machine.

Penambahan Fitur Tampilan LCD dan Micro SD Card Reader pada mesin Laser Engraver and Cutter di Laboratorium Pengemudian Listrik

Laser engraver and cutter machine that have been made in previous research, can only be controlled by a computer. The addition of LCD display and Card Reader will make it work alone without using a computer (offline). Card reader is used to read gcode files from 2-dimensional design that have been made on a computer. LCD display is used to display a menu or a list of existing settings, the percentage of loading data from a gcode file and displays the 2-dimensional design of the gcode file. To move the menu on the LCD display an encoder switch is used. This additional feature was created using a microcontroller STM32F1 type as a core control system which performs serial communication with a laser machine. 32 bit ARM microcontroller is used because a lot of tasks has to perform. It must be able to read data from the SD card, display the image form from the gcode file and send it to the laser machine. Compared 3 types of gcode file of different file sizes and the speed of loading the data. The laser machine can perform its function by using the controls of the additional feature modules that have been made.

Residual Stress in Soldering and Brazing Between Cemented Carbide and Steel Substrate of Shield Machine Cutters

Residual Stress in Soldering and Brazing Between Cemented Carbide and Steel Substrate of Shield Machine Cutters

Risk assessment and management via multi-source information fusion for undersea tunnel construction

The construction of undersea tunnels is an extremely risky endeavor that is vulnerable to water seepage and gushing due to the high water pressure, complex geological conditions, and pore water trapped in unstable rocks. This risk can lead to the collapse of tunnels under construction and disastrous consequences of fatalities and injuries as well as project delays and financial losses. The current risk management practices for tunnel construction projects in China are static and rely on the subjective judgement of experts and practitioners and do not incorporate real-time monitoring data during the construction process at this time. This paper presents a new method and system to assess and manage the risks during the construction process by coupling the risk management system and the quality management system and integrating jobsite monitoring data, design data, and environmental data. In this new method and system, the risk factors are categorized into (hu)man, material, machine, method, and environment, or 4M1E, and are quantitatively measured. The Dempster-Shaffer (D-S) theory was adopted in this method to both fuse the 4M1E data and to compute the aggregate risk index. This new method and system was tested during the Xiamen Metro Line No. 3 project when a shield machine cutter accident occurred. The results show that, before the accident, the individual risk measures in all five dimensions (4M1E) and the aggregate risk index were extremely high, which clearly illustrated the feasibility and capability of the newly developed method and system.

Application of cryo-treatment for improving machining characteristics and reduce manufacturing cost

With the improvement of super-hard materials (intrinsic compounds and extrinsic compounds) the cutting of these materials turns into a matter of worry as far as their quality and quantity. So as to cut such tough materials assortment of inserts are being applied at contemporary.Concentrate on cryo-treatment which is otherwise called a method forever expanding cure for enlightening the properties of the various cutting tools. Examination of impact of profound cryo-treatment at ‘−185 °C’ on P.V.D treated and C.V.D coated tungsten carbide (WC) supplements (inserts) has been appeared in the investigation, which has been trailed by different microstructural and mechanical investigation, for example, Flank Wear test, Hardness test, Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray Spectroscopy (EDS) examination and so on. The examinations was done on both untreated and treated supplements. With SEM examination impact of cryogenic treatment on the microstructure was identified and EDS investigation was used to identify chemical portrayal.Cryogenically treated supplements (inserts) were executed on Rolling shaper and D2 Roll at Ludhiana. With the application of cryogenic cured supplements (inserts) in the industry, it has been seen that the life of Rolling Cutter machining increased by 19 percent and 50 percent of life increased in D2 Roll machining and complete benefits after usage was seen Rs. 90,360 every year.

Journal Review

Journal Review

The Effect of Heat Treatment Conditions on the Mechanical Behavior of Ni-Ti Shape Memory Alloys

Ni-Ti shape memory alloy (SMA), and its alloys have been widely used for medical, mechanical and electrical applications. In this study, a (Nitinol) Ni-Ti alloy medical plate was prepared and cut using a wire cut machine. Eight samples were heat treated at 800°C and used for heating samples for 30 min and 60 min at this temperature, then cooled in four media: furnace, water, air, and ice bath. Micro-hardness and microstructure measurements were taken, as characterization techniques, to investigate the effect of cooling rate on mechanical properties. Micro-hardness results showed the HV is 316.36 HV at ice cooling rate for 800 °C and 60 min heating time, and 275.5 HV for 800 °C heating for 30 min and ice cooling media. The results show the correlation between cooling rate and properties of the alloy.

Ağaç Malzemelerin Daire Testere Makinelerinde İşlenmesinde Testere Geometrisi ve Uygulama Koşullarının Önemi

Circular saw machines are usually used for cutting of the edge flattened parts to desired dimensions and angles, sizing of panels, grooving, jointing, rebating, etc. For this purpose, it can be stated that the selection of the cutter in machining is very important in terms of product quality and efficiency. It can be indicated that the main factors affecting saw blade selection are material density and humidity, cutting edge shape and type with rake and tool angle. In this study, saw blade geometry, its selection and factors affecting the process were studied in the machining of wood materials in circular sawing machines. Also, the problems and solutions proposal encountered in the circular saws during in sizing are stated.

Pembuatan dan Pengujian Mesin Pemotong Lidi Tusuk Sate

MAKING AND TESTING OF SKEWERS CUTTING MACHINES. In Indonesia there are more than 100 types of bamboo that can be used by craftsmen, one of which is skewers. Skewers are promising commodities for business opportunities. The process of producing skewers are started from cutting down the bamboo, cutting bamboo, splitting bamboo, shriveling bamboo to become a stick skewer after that is done cutting the skewer sticks, drying sticks, polishing the sticks skewers and chopping sticks. The process of cutting a stick skewer which is done at this time is still using a simple tool, so the results are bad and the cutting time is very long. To maintain the quality of the results of a good stick skewer sticks and to increase the productivity of the stick skewers, the process of producing and testing of a skewer stick cutting machine is done. The method to produce a skewer stick cutting machine is done by designing the tool, determining the material to be used then making it. This skewer stick cutting machine is made with a press system and vertical cutting directions. From the results of testing the skewer stick cutting machine obtained that the quality of skewer cutting is good and the time required to cut is only 10 seconds. the difference is about 50 seconds faster than the hand saws used, so as to increase the productivity of the skewer sticks. The cutting machine was impelemented at home industry at Sidomulyo of South Lampung. Using the machine has increased productity and also quality of skewers.

A novel polycaprolactone/carbon nanofiber composite as a conductive neural guidance channel: an in vitro and in vivo study

The current study aimed to investigate the potential of carbon nanofibers to promote peripheral nerve regeneration. The carbon nanofiber-imbedded scaffolds were produced from polycaprolactone and carbon nanofibers using thermally induced phase separation method. Electrospinning technique was utilized to fabricate polycaprolactone/collagen nanofibrous sheets. The incorporation of carbon nanofibers into polycaprolactone’s matrix significantly reduced its electrical resistance from 4.3 × 109 ± 0.34 × 109 Ω to 8.7 × 104 ± 1.2 × 104 Ω. Further in vitro studies showed that polycaprolactone/carbon nanofiber scaffolds had the porosity of 82.9 ± 3.7% and degradation rate of 1.84 ± 0.37% after 30 days and 3.58 ± 0.39% after 60 days. The fabricated scaffolds were favorable for PC-12 cells attachment and proliferation. Neural guidance channels were produced from the polycaprolactone/carbon nanofiber composites using water jet cutter machine then incorporated with PCL/collagen nanofibrous sheets. The composites were implanted into severed rat sciatic nerve. After 12 weeks, the results of histopathological examinations and functional analysis proved that conductive conduit out-performed the non-conductive type and induced no toxicity or immunogenic reactions, suggesting its potential applicability to treat peripheral nerve damage in the clinic.

Rapid Manufacturing of Thin Soft Pneumatic Actuators and Robots.

This protocol describes a method for rapid manufacturing of soft pneumatic actuators and robots with an ultrathin form factor using a heat press and a laser cutter machine. The method starts with the lamination of thermoplastic polyurethane (TPU) sheets using a heat press for 10 min at the temperature of ~93 °C. Next, the parameters of the laser cutter machine are optimized to produce a rectangular balloon with maximum burst pressure. Using the optimized parameters, the soft actuators are laser cut/welded three times sequentially. Next, a dispensing needle is attached to the actuator, allowing it to be inflated. The effect of geometrical parameters on the deflection of the actuator are studied systematically by varying the channel width and length. Finally, the performance of the actuator is characterized using an optical camera and a fluid dispenser. Conventional fabrication methods of soft pneumatic actuators based on silicone molding are time consuming (several hours). They also result in strong but bulky actuators, which limits the actuator's applications. Moreover, microfabrication of thin pneumatic actuators is both time-consuming and expensive. The proposed manufacturing method in the current work resolves these issues by introducing a fast, simple, and cost-effective fabrication method of ultrathin pneumatic actuators.

A Study on Effect of Tool Wear Rate upon Cutting Tool Shape in a Titanium Rough Cut Machining

A Study on Effect of Tool Wear Rate upon Cutting Tool Shape in a Titanium Rough Cut Machining

Design of Integrated Cutter System for Machine Cutter Change of Tunnel Boring Machine

Tunnel boring machine is widely used in underground engineering construction. During the construction process, the cutter frequently detects and replaces the construction efficiency and harms the safety of the cutter changer. It is imperative to realize the cutter change "Machine replacement manual". Traditional cutter fasteners are numerous and discrete, and their shapes and sizes are different. To design an automatic cutter changer for this structure, the actuator design will be very difficult. Designing an integrated cuttering system that is easy for machine operation is essential for “machine replacement manual”. In view of the above problems, this paper proposes an integrated cutter system scheme with three different structures according to the idea of integrating cutter, locking block and bolt. 7 performance indicators for integrated cutter evaluation for machine cutter change operation: static stiffness, static strength, weight, three-dimensional size, extraction size, disassembly action and pre-tightening force. Contrasting and analyzing the three integrated structural schemes and the various indicators of the traditional cuttering scheme, and obtaining an optimal cuttering scheme for machine cutter change.

Experimental investigation on precision machining of multiple holes by WEDM on Aluminium-6061 using genetic algorithm

Aluminum base alloys used in aeronautical applications is machined using WEDM to machine complex profiles with good accuracy and minimum taperness. This present investigation explores wire cut EDM machine tool usage for optimization process variables of Aluminium-6061 alloy. A Sequence of experiments are developed to research the process parameters, effects such a pulse on time—TON, wire feed rate—WFR, pulse off time—TOFF and servo voltage control—SVC on dimensional deviation—DD, Taperness, wire wear rate—WWR and metal removal rate—MRR. Trial runs on Al-6061 are conducted by taguchi design of experiments, a regression equation is developed. Genetic algorithm optimization technique is applied to yield global optimum results for optimizing process variables. Finally, comparison done across experimental results to predicted values for effectiveness 95% of confidence level was obtained. The optimum levels for getting minimum taperness is identified for square geometry are pulse on time—103 µs, pulse off time—59.99 µs, wire feed rate—6.45 mm/min and control of speed—92.52%. For circular geometry the identifications are pulse on time—103 µs, pulse off time—59.99 µs, wire feed rate—7.88 mm/min and control of speed—42.34% for optimum response. The optical microscope conformation test has obtained with satisfactory.

Effect of Current and Wire Speed on Surface Roughness in the manufacturing of Straight Gear using Wire-cut EDM Process

The gears are an important part of a mechanism. Making gears requires high precision to avoid backlash. The machining process that can produce high precision is the process of Wire cut EDM. This study aims to determine the roughness of the workpiece surface and investigate the effect of current and wire speed on the roughness of the straight gear surface through wire cut machine EMS 45. The wire cut machining parameters used are 3, 5, and 7 amperes for current, and wire speed of 8, 10, and 12 mm/min. While the Wire material is a type of brass with 0.25 mm in diameter. The results presented that the increased use of current and wire speed will result in lower surface roughness, and vice versa. Therefore, it can be concluded that use low machine parameters to produce a smooth workpiece surface.

A Tracking-Based Numerical Algorithm for Efficiently Constructing the Feasible Space of Tool Axis of a Conical Ball-End Cutter in Five-Axis Machining

To meet the high requirement on cutter stiffness in five-axis machining of complex parts with deep channels, such as an aero-engine blisk, conical ball-end cutter is preferred over the traditional cylindrical cutter as the former can increase the stiffness ten folds or more over the latter of a same size. However, because the shank of conical ball-end cutter is a cone instead of a cylinder, when calculating the feasible space of tool axis (FSTA) for any given center of the ball-end, the line-visibility, which is critically utilized in the case of cylindrical ball-end cutter, is no longer applicable. Currently in practice, the calculation of FSTA for the conical ball-end cutter has to resort to the simplest brute-force approach of checking for collision for every sampled tool axis. This process of exhaustive collision checking is extremely time-consuming and lacks accuracy, as there are typically thousands of center points of ball-end on a five-axis tool path, and for each of them there can be again thousands of sampled tool axes to check for collision, which is itself a very time-consuming task. In this paper, we propose a tracking-based numerical algorithm for constructing FSTA of the conical ball-end cutter amid an obstacle environment defined by freeform surfaces. Our algorithm avoids the time-consuming collision checking by directly tracing out the characteristic curves on the boundary surfaces of obstacles. As a result, it not only tremendously reduces the computing time by only searching around the boundary of FSTA, but also substantially improves the accuracy of the final constructed FSTA as the step size of tracing can be set sufficiently small without increasing much on the computing time. Simulation tests of the proposed algorithm are also reported to validate its time efficiency and accuracy.

A radius compensation method of barrel tool based on macro variables in five-axis flank machining of sculptured surfaces

Barrel tool radius compensation is very important to improve the five-axis CNC machining precision and efficiency of sculptured surfaces. By combining macro variables and math function of CNC controller, a radius compensation method of barrel tool based on macro variables in five-axis flank machining of sculptured surfaces was presented. The basic principle of barrel tool radius compensation in five-axis flank machining was firstly investigated. For a specific five-axis CNC machine tool with dual rotary tables, a relationship equation between compensated cutter location (CL) data and machine control (MC) data could be derived. A post-processor with the function of five-axis barrel tool radius compensation was then developed by using the C++ language, which could generate the NC programme with macro variables of barrel tool radius compensation. Finally, the NC programme was obtained automatically by the developed post-processor for the aero-engine blade surface machining. The machining process was simulated on the software VERICUT, and machining experiments were also conducted on the five-axis machine tool. Both the simulation and experimental results showed that the proposed method could perform the function of barrel tool radius compensation in the NC programme for five-axis flank machining.