Conventional Cutter Research Articles

Study of rock-breaking performance of V-axe-shaped PDC cutter in tight sandstone formation

In the field of oil and gas drilling engineering, tight sandstone strata are one of the strata that are difficult to drill. The V-axe-shaped cutter has a good effect in crushing tight sandstone strata. However, there were few studies on its specific structural parameters and rock-breaking performance in tight sandstone formations. To further explore its structural parameters and rock-breaking performance, this paper studies the rock-breaking performance of a V-axe-shaped PDC cutter in tight sandstone formation by combining experiments with finite element simulation. Mechanical tests show that the compressive strength is high, with values of 130.3 MPa, 223.3 MPa, and 271.6 MPa under confining pressures of 0/15/30 (MPa), respectively, with the condition of 0.02 mm/min loading rate. Rock lithology tests that the sandstone in this formation has strong abrasiveness. The penetration ability should be considered when evaluating the rock-breaking performance of cutting cutters. The results show that the V-axe-shaped PDC cutter mainly uses shear, extrusion, and point load to break rock together. It has a stronger ability and stability to attack the rock. With a 100° V-shaped angle (α) and 140° Axe-shaped angle(β) has the best rock-breaking property. The back-rake angle of the cutter can reduce cutter vibration and significantly improve PDC bit rock-breaking efficiency. The optimal rock-breaking back-rake angle of the V-axe-shaped cutter is 20° in dense sandstone formations. With the increase of wear height(0–3 mm), the synthetical mechanical specific energy (MSE) is reduced by 11.53%, 6.30%, 10.30%, and 33.28%, respectively, compared with the conventional cutter. The tests indicate that the rock-breaking efficiency of the V-axe-shaped PDC cutter is 12.9% higher than that of the conventional PDC cutter. The application of V-axe-shaped cutters on the bit is expected to improve the rock-breaking efficiency and footage of PDC bit in tight sandstone formations and realize the development of low-cost and high-benefit oil and gas resources.

Design and Fabrication of Chaff Cutter Machine

India is an agricultural nation with the majority of its population residing in rural areas. The rural landscape is predominantly occupied by agricultural activities, including crop production and poultry farming by using of chaff cutter machines. The conventional cutter machines are unsafe design resulted in severe injuries and needed more workforces. Taking into consideration the limitations of the current conventional cutter machine, this project has been undertaken to develop and manufacture a chaff cutter machine, aiming to mitigate the potential for serious injuries and enhance operational efficiency. First of all, the work of design of the chaff cutter machine will be developed and analyzed. The new chaff cutter machine will be tried out for cutting various types of animal feed like dry straw, grass, corn straw, wheat stalk, etc. We'll also check how cost-effective the new machines are compared to the old-style ones and newer models. This paper talks about how we made and tested a chaff cutter machine in India. We'll also look at how much it costs to use the new chaff cutting machine compared to the old ones.

Optimization of Milling Tool Parameters and Experimental Research on Titanium Alloy TC11

Because of its high strength and poor thermal conductivity, TC11 alloy has some problems such as high cutting force and serious tool wear. To solve the problems, the finite element simulation and milling TC11 experiment are combined to research tool selection, cutting force, cutting vibration, and so on. First of all, the simulation and experiment of the cutting force are carried out, the prediction model is established, and the cutter parameters are optimized; Secondly, the milling experiment is carried out to compare and analyze the change rules of force and vibration when cutting with an optimized milling cutter and conventional cutter, and the best cutting parameters are selected; Finally, the tool life of milling TC11 under different cooling and lubrication conditions is explored.

Comparison of fracture characteristics of different PDC cutters penetrating carbonate rock

Carbonate rock is a very important reservoir rock in many parts of the world, but due to high temperature, high hardness, strong abrasiveness and other reasons, PDC (Polycrystalline Diamond Compact) bit is seriously worn and the efficiency of breaking rock is low. To solve this problem, a lot of research has been carried out on the cutting mechanism of PDC cutters, but less research has been done on the crushing mechanism of PDC cutters penetrating carbonate rock. Actually, effective penetration can increase the cutting depth and change failure mode of rock. Furthermore, the PDC cutter penetration process will also cause damage to the rock, which is conducive to improving the subsequent efficiency of cutting rock. Therefore, the study of PDC cutter penetrating rock characteristics can provide theoretical basis for drilling parameter optimization and PDC bit structure design. In this paper, the crushing mechanism of PDC cutters penetrating carbonate rock was studied. Based on the hydraulic servo experimental system and ST400 3D Profilometer, a series of experiments were carried out on conventional cutter, axe cutter and conical cutter penetrating carbonate rock at different back rake angles. The penetration force-penetration depth curve and surface topography of broken pits were analyzed. The results show that the failure mode of carbonate rock is affected by the back rake angle of cutter. Conical cutter has strong aggression when penetrating at a small back rake angle. The expansion of axe-shaped angle of the axe cutter exacerbates the failure of carbonate rock. Moreover, at the back rake angle of 10° and 20°, the maximum penetration depth and penetration efficiency of conical cutter were significantly greater than those of conventional cutter and axe cutter. At the back rake angle of 30° and 40°, the maximum penetration depth of axe cutter is greater than that of conventional cutter and conical cutter. The research results are expected to provide theoretical guidance for the optimized design of PDC cutter shape and back rake angle.

Experiments on the Novel Chord-Edge Cutter to Break Rock with Higher Efficiency and Its Field Application

Summary Aiming at the difficulty of penetration in hard-plasticity formation represented by the Mahu oil field, a new type of chord-edge cutter is proposed. Through theoretical derivation and quantitative analysis of specific unit pressure (SUP) and breaking area, the penetration and rock-breaking area of the chord-edge cutter are studied, which clarifies that the rock-breaking efficiency of the chord-edge cutter is higher than that of the conventional cutter. The first part of the laboratory experiment investigated the drilling efficiency of two mini-bits on a special sample. The results show that the chord-edge cutter mini-bit has higher efficiency than a conventional mini-bit. The second part of the laboratory experiment investigated the influence of rate of penetration (ROP), revolutions per minute (RPM), and rock types on the drilling performance of chord-edge cutter mini-bit. The data show that the chord-edge cutter is more suitable for drilling hard-plastic rocks. It also reveals that the higher the RPM, the lower the stick/slip vibration, but the RPM above a certain value will lead to an increase in lateral vibration. ROP and weight on bit (WOB) are positively correlated. And the higher the drilling speed, the higher the stick/slip vibration and lateral vibration. To verify these conclusions, a field test is carried out in the hard-plastic formation of a well in the Mahu. In this test, compared with a conventional polycrystalline diamond compact (PDC) bit, a roller-cone bit, and a hybrid bit, the chord-edge cutter bit has the best drilling effect. Further, it is found that when using the chord-edge cutter bit, the high RPM and proper control of WOB can achieve a better drilling efficiency. This rule is mutually confirmed with the conclusion of the laboratory experiment. After the above research and its implementation, it can be concluded that the novel chord-edge cutter bit can achieve the research goal of higher efficiency, which provides a new idea to overcome challenges in the hard-plastic strata.

Finite element simulation of plough cone cutter

In order to improve the ROP of the PDC bit, a plough cone cutter was designed and finite element simulation was performed. Compared with conventional cutter, plough cone cutter has smaller stress field and strain field in the rock breaking process. The largest tangential rock breaking force and maximum axial rock breaking force is higher, but the average tangential rock breaking force and the average axial rock breaking force are smaller, and the rock breaking effect is better; the back dip angle has a significant impact on the rock breaking effect. Under the same plough cone cutter, with the increase of the inclination angle, the stress field and strain field of the rock after rock breaking will become smaller, and the rock breaking effect will be better. Therefore, the plough cone cutter with a backward inclination angle of 22° has an advantage in the rock breaking process.

Study on rock-breaking mechanism of axe-shaped PDC cutter

Polycrystalline diamond compact (PDC) cutter is the key component of a drill bit. Recently the shaped PDC cutters, especially the axe-shaped cutter (ASC), have been warmly welcomed by the drilling engineers. However, the rock-breaking mechanism of ASC is rarely studied. In order to investigate the cutting action of ASC, comparative experiments of ASC and conventional cylinder-shaped cutter were carried out based on a vertical turret lathe (VTL). VTL tests' procedure were modified to mimic the initial state, steady state of PDC cutter in the real down hole drilling. The cutting forces and temperature were measured using a dynamometer load cell (3-component force sensor) and a thermocouple, respectively. The results show that ASC has better wear resistance and cutting efficiency than the conventional cylinder-shaped cutter. ASC is easier to press into the rock with its pointed geometry, leading to lower normal force at the initial state of cutting. The cutter shape has large influence on the cutters’ resistance to impact. In addition, both the normal force and tangential force required by ASC during stable cutting are less than that of conventional cylinder-shaped cutter under the same test conditions. Although the cuttings produced by both ASC and conventional cutter have pretty similar particle size distributions, ASC consumes less energy to break the rock based on the fractal analysis of cuttings. • Two states of PDC cutters were simulated on vertical turret lathe. • Consider fractal analysis into cuttings analysis of PDC cutters. • The wear resistance of PDC cutters were compared. • A new experimental attempt to explore the impact resistance of PDC cutters.

3D numerical simulation study of rock breaking of the wavy PDC cutter and field verification

The structure of polycrystalline diamond compact (PDC) bits is a key factor in improving their rock-breaking efficiency. To further study the rock-breaking mechanism of the wavy PDC cutter, a 3D finite element model of the dynamic rock breaking of the PDC cutter was established, and a comparative study on the rock-breaking process of the wavy PDC cutter and the conventional PDC cutter was conducted. The results show that the wavy PDC mainly breaks the rock by ploughing and shearing, which results in a higher rock-breaking efficiency. The cutting force of the wavy PDC cutter is 6.64% lower than that of the conventional PDC cutter, and its fluctuation is obviously smaller. With an increase in back-rake angle, the cutting force, its fluctuation, and the mechanical specific energy (MSE) increase, and the optimal back-rake angle is 10°–15°.With an increase in cutting depth, the cutting force and its fluctuation in the wavy PDC cutter increase, the MSE decreases, and the optimal cutting depth is 2 mm. As the number of waves increases, the cutting force and MSE of the PDC cutter increase first and then decrease, and the greater the number of waves, the larger the fluctuation of the cutting force. The cutting temperature of the wavy PDC cutter is lower than that of the conventional cutter, it decreases with an increase in the back-rake angle and number of waves, and gradually increases with an increase in cutting depth. The main results of this work will help to reveal the process of rock breaking and the mechanism of the wavy PDC cutter, thus contributing to the achievement of a high rate of penetration and efficiency in the drilling process of hard formations with PDC bits.

Optimal Design and Experimental Verification of Ultrasonic Cutting Horn for Ceramic Composite Material

We developed and optimized a block-type ultrasonic horn that can be used for cutting hard materials. The proposed block-type sonotrode consists of an aluminum horn and a tungsten carbide blade to increase the cutting of hard materials. We designed an initial ultrasonic block horn that has double slots and an exponential stepped profile. We developed a finite element model of the initial model and analyzed the characteristics of natural frequency and displacement. We formulated a DOE table and response surface to perform sensitivity analysis and analyze the correlation between the design variables and characteristics of the proposed block horn. The optimal ultrasonic block horn was derived via a multi-objective optimal design problem to maximize the amplitude uniformity of the proposed horn and frequency separation. We fabricated the optimal block horn and verified it experimentally. An ultrasonic cutting experiment was conducted to find the ultrasonic cutting force with hard ceramic composite materials. A cutting test with a conventional cutting machine under the same condition was also conducted to compare the cutting force. The proposed optimal ultrasonic cutter requires 70% less cutting force than the conventional cutter to cut a ceramic composite material and the cutting surface with the application of the proposed optimal ultrasonic cutter is much cleaner with no crack and delamination than that with the application of the conventional cutter.

Cutting Mechanism Study of an Innovative Non-Planar Cutter PDC Bit and Its Field Application

Tarim Kuqa tight sandstone reservoir is overlaid with extreme thick conglomerate, which has high compressive strength, strong heterogeneity and poor drill ability, resulting in low drilling ROP and less bit drilling footage. Through research study and analysis of PDC bit failure and wear modes, this paper described the development of an innovative non-planar PDC bit through cutting mechanism study and lab testing verification. When drilling through the strong homogeneity formation, it will still be surface contact between the non-planar cutter and the rock and therefore the rock-breaking mechanism is still the conventional shearing fracturing; When drilling through the heterogeneity formation, the convex ridges will generate the linear contact with the hard rock and the mechanical stress will be accumulated at the conglomerate surface to initially create the cracking and then break the rock with composite cutting mechanism of shearing and crushing to improve the rock breaking efficiency. Experimental results also showed that the non-planar cutter delivers several folds of impact resistance improvement over conventional cutter. The bit was successfully field tested in ultra-thick conglomerate layer in the Kuqa foreland thrust belt of the Tarim basin. The field test tripled bit footage and doubled ROP comparing to same intervals and formation in offset wells. It demonstrated the broader prospect of the non-planar PDC technology in conglomerate and highly heterogeneous applications.

3D Numerical Simulation of Rock Cutting of an Innovative Non-Planar Face PDC Cutter and Experimental Verification

The low rock breaking efficiency of conventional polycrystalline diamond compact (PDC) bits in hard abrasive formations prompts the development of PDC cutting elements from the planar structure to the non-planar structure. As an innovative non-planar cutter, the design and research of the three-ridged diamond element (3-RDE) cutter is still in its infancy, and its rock breaking mechanism and laws are not yet clear. In this paper, a three-dimensional (3D) finite element model of dynamic rock breaking with 3-RDE cutter has been established. The accuracy of the numerical model was verified by experimental data. Then, the difference of rock breaking mechanism between 3-RDE cutter and conventional cutter was studied. The effects of back-rake angle, cutting depth, rotational angle, and rock properties on rock breaking efficiency were also analyzed. The results show that, unlike the conventional PDC shear rock breaking cutter, the 3-RDE cutter breaks rock mainly by crushing and shearing, and the rock breaking efficiency is higher. A small back-rake angle and reasonable cutting depth contribute to improving the rock breaking efficiency; the existence of rotational angle is not conductive to the rock breaking. The field application shows that compared with the conventional cutter, the 3-RDE cutter is easier to penetrate into the formation, and is more stable with less torque required. The research results can be of benefit to the design and manufacture of 3-RDE PDC bits.

Specially Designed Lattice Structure for Milling Cutter Supported by FEA

Lattice structures are one way to reduce the weight of a component while respecting its strength requirements. These structures are based on cubic cells, therefore, they are not fully applicable to rotating parts which should be lightweight. This article particularly addresses this issue. A solution is sought for how to adapt lattice structures for a milling cutter. The final redesign of the topology allows a continuous flow of generated stress into the whole body of the cutter. Further, the solid part of the milling cutter is modified for Metal Additive Manufacturing (MAM) and the functionality of the optimised cutter is verified by Finite Element Analysis (FEA). The results of the analysis are compared with a conventional cutter with the same outer shell. The findings from the static analysis indicate that the milling cutter can be considered to be competitive.

Development of stripper harvester for paddy

Konkan is the coastal part of Maharashtra between Western Ghat and Arabian seacoast. Rice is a major crop grown over 3.86 lakh hectares. Stripper harvesting technology, which strips only seeds and keeps straw erect-ed in the field present bright prospect for the development of small, light, efficient mechanism by reducing number of operation with increased capacity and lesser power compared to conventional cutter bar combine harvester. The big machines like combine harvester and high capacity threshers for harvesting and threshing have limitations. A proto-type of paddy stripper harvester was developed considering the limitation of Konkan like small, fragmented land, hilly, terrace farming and high rainfall. It consisted of stripping mechanism, grain tank, hydraulic system, steering system, gear box, engine, cage wheel and chassis. The arrangement of V-belt and set of pulleys were made to transmit power from gear box to stripper rotor. The effect of forward speed and peripheral speed on shattered and un-stripped grain loss was studied. The shattered grain loss was decreased with increase in forward speed whereas decreased initially and then increased with increase in peripheral speed. The un-stripped grain loss was decreased with increase in forward and peripheral speed. The performance of the developed prototype was found better at forward speed of 2.25 km/h and peripheral speed of 19.78 m/s. During final testing of prototype, shattered and un-stripped grain loss was found 5.95 and 1.89 %, respectively. The average field capacity and field efficiency of paddy stripper harvester machine was found 0.14 ha/h and 69.38 per cent respectively.

Cutting force and machine kinematics constrained cutter location planning for five-axis flank milling of ruled surfaces

Abstract Five-axis flank milling has been commonly used in the manufacturing of complex workpieces because of its greater productivity than that of three-axis or five-axis end milling. The advantage of this milling operation largely depends on effective cutter location planning. The finished surface sometimes suffers from large geometrical errors induced by improper tool positioning, due to the non-developability of most ruled surfaces in industrial applications. In addition, a slender flank-milling cutter may be deflected when subjected to large cutting forces during the machining process, further degrading the surface quality or even breaking the cutter. This paper proposes a novel tool path planning scheme to address those problems. A simple but effective algorithm is developed to adaptively allocate a series of cutter locations over the design surface with each one being confined within an angular rotation range. The allocation result satisfies a given constraint of geometrical errors on the finished surface, which consists of the tool positioning errors at each cutter location and the sweeping errors between consecutive ones. In addition, a feed rate scheduling algorithm is proposed to maximize the machining efficiency subject to the cutting force constraint and the kinematical constraints of a specific machine configuration. Simulation and experimental tests are conducted to validate the effectiveness of the proposed algorithms. Both the machining efficiency and finish surface quality are greatly improved compared with conventional cutter locations. Highlights Tool position is bounded with respect to the geometrical machining error. Cutting force and kinematics during five-axis flank milling process are analyzed. An incremental adaptive flank milling tool path generation algorithm is proposed. Feed rate is smoothly assigned respecting cutting force and kinematic constraints.

Milling research and tool selection design of SiC14Cu4Mg0.5Si based on Aluminium matrix 2A14

The selection of milling tools for SiC14Cu4Mg0.5Si based on Aluminium matrix 2A14 was analyzed, and the factors that affect the efficiency of the milling were discussed. The SiC14Cu4Mg0.5Si was designed for use on the moon landing vehicle or missile wings, but the hardness of aluminium-silicon carbide composite material was very high, much higher than the general hardness of cemented carbide, which will bring many difficulties in the aluminium-silicon carbide composite material processing. The chemical compositions of SiC14Cu4Mg0.5Si were analyzed. A new selected indexable cutter was designed to mill SiC14Cu4Mg0.5Si. The structure design of milling cutter was different from the conventional milling cutter, breaking the previous limitations to a certain extent, pioneering the idea. The tool material wear was detected by experiments. The mechanical and physical properties of SiC14Cu4Mg0.5Si were also tested. SiC14Cu4Mg0.5Si exhibited different surface quality characteristics under different milling tools.

An accurate approach to determine the cutting system for the face milling of hypoid gears

In this research, mathematical model of an accurate cutting system for the face milling of hypoid gear is developed. For the machining of hypoid gear, a conventional cutter system is considered, which contains the groups of inside and outside blades. These blade models are called accurate due to the consideration of rake, hook, relief and pressure angles in the design. Mathematical representation of the tooth cutting edges of the blades is developed. By assembling the blade models in the cutting system and revolving it around the cutter rotation axis, swept surface and profiles of inside and outside blades are generated. Using the local synthesis method, determination of cutting system geometry is performed for the given parameters of the gear. In cutting system parameters, average cutter radius and pressure angles of the tooth cutting edges are the variables in this algorithm, whereas the hook, rake and relief angles are assumed to be given. Sensitivity analysis is performed, to analyse the sensitivity of the cutting surface, with respect the blade’s rake and hook angle. Finally, an application is presented for a standard gear geometry. A cutter system is determined for the gear and it is virtually face milled, and the geometric parameters are validated against the given parameters of the gear.

Small infrared target detection using sparse ring representation

A new approach, SRR, for small infrared target detection in single image is described herein. SRR is based on local self-similarity descriptor, according to the characteristics of small infrared targets. Using the SRR, the certainty of small targets can be easily measured. Compared to some conventional cutter removal methods, extensive experimental results show that the proposed approach outperforms these methods. Additionally, the proposed approach has a simple structure, which is convenient for implementation. Plans for future research include incorporating efficiently temporal information to further improve detection performance.

BGA cutter improvement utilizing nano-TiAlN coating layers synthesized by cathodic arc ion plating process

Ti/Al targets with various concentration ratios, Ti 0.75Al 0.25, Ti 0.66Al 0.33, Ti 0.5Al 0.5 and Ti 0.33Al 0.66 were used in a filtered cathodic arc ion plating system (FCAIP) to deposit the multilayer TiAlN films on Si wafer substrates and WC cermet ball grid array (BGA) cutters at various modulation wavelengths. Transmission electron microscopy (TEM), nanoindentation and BGA router were used to evaluate the characteristics of TiAlN layers and the performance of BGA cutters. TEM analysis revealed that the modulation wavelengths of deposited layers are less than 10 nm at various rotation speeds in FCAIP chamber and the crystal structure of TiAlN layer with the maximum hardness is NaCl-B1 structure using the Ti 0.5Al 0.5 target. The maximum hardness of multiple TiAlN layers measured by nanoindentation was 43 GPa, while the TiAlN monolayer exhibited the maximum hardness of 30 GPa in the same chamber. The TiAlN-coated BGA cutter deposited at the optimized condition exhibited a twice longer life and a higher machining speed in comparison with the conventional cutter.

Análise do movimento e desenvolvimento de um protótipo de cortador basal com discos bi-articulados

O acompanhamento da superfície e a autoproteção, são fatores limitantes no mecanismo cortador de base convencional da cana-de-açúcar, acarretando corte e varredura ineficientes, além de promover a incorporação de elevada quantidade de terra ao material colhido. Um modelo de simulação foi desenvolvido por meio das leis da dinâmica para determinar os deslocamentos angulares do segmento no plano vertical, da faca no plano horizontal e da força de interação do segmento com a superfície. A simulação do mecanismo foi realizada em duas velocidades (400 e 600 rotações min-1), três alturas com relação à superfície (120, 130 e 140 mm) e duas inclinações do rotor (-10 e -12º). O resultado da amplitude de oscilação do segmento, variável relacionada à varredura, apresentou valores entre 2,1 e 9,5º; a oscilação da faca apresentou variações angulares desprezíveis durante a simulação e a força de reação com a superfície, que está relacionada à movimentação de terra e danos à soqueira, apresentou valores entre 941 e 2654 N. Em função dos resultados, observa-se que recursos virtuais de simulação se apresentam como poderosa ferramenta na tomada de decisões e no desenvolvimento de novos mecanismos.

Design and analysis of a milling cutter with the improved dynamic characteristics

In this paper, a face-milling cutter is proposed and manufactured to improve a cutter’s dynamic characteristics. The proposed cutter, comprises double step blades, and is designed to give better stability in terms of vibration and to suppress the possibility of abrupt wear and chipping. Vibration experiments with the conventional type and the proposed cutter were performed, and the results showed that the vibration amplitude in the time domain and the peak value in the vibration spectrum in the frequency domain are considerably lower for the proposed cutter than for the conventional cutter. In addition, the validity of a cutting dynamics model, which can effectively predict the cutting dynamics on the machine–tool–workpiece (M–T–W), was examined by the vibration experiments.