High Pressure Abrasive Water Jet Research Articles

Analysis and Basics of Improving the Process of Cutting Electrical Sheet Bundles with a High-Pressure Abrasive Water Jet.

Electrical steels are widely used in the electrical industry in the construction of many devices, e.g., power transformer cores and distribution transformers. An important parameter of electrical components that determines the efficiency of devices is energy loss during remagnetization. These losses are influenced, among other factors, by steel cutting processes. The common techniques for cutting electrical materials on industrial lines are mechanical cutting and laser cutting. High-pressure abrasive water jet (AWJ) cutting, unlike the technologies mentioned above, can ensure higher quality of the cut edge and limit the negative impact of the cutting process on the magnetic properties of sheet metal. However, the correct control of the process and the conditions of its implementation comprise a complex issue and require extensive scientific research. This work presents a new approach to cutting electric sheets, involving bundle cutting, which significantly increases the processing efficiency and the dimensional and shape accuracy of the cut details. The tests were carried out for bundles composed of a maximum of 30 sheets, ready to be joined in a stator and rotor in a motor. The influence of processing conditions on the quality of the cut edges of sheet metal, the width of the deformation zone, and the burr height were analyzed. The detailed analysis of the quality of the cut edges of electrical bundled sheets creates new possibilities for controlling the AWJ cutting process in order to obtain a product with the desired functional and operational properties.

Influence of the cutting edge preparation of carbide punching tools for punching of ultra-high strength steel strips

In order to ensure a robust punching process of ultra-high strength steel spring strips using carbide punching tools, a high stability of the cutting edge is required. Here the cutting edge preparation process has a significant influence. In the presented study, high-pressure abrasive water jet technology for cutting edge preparation was designed, investigated and analysed. For defining the optimal cutting edge shape regarding stresses, a numerical analysis using LS-DYNA was conducted. Within this analysis, the influence of the cutting edge rounding and symmetry was numerically tested and evaluated. Based on the results, two cutting edge shapes were selected and prepared using the high-pressure abrasive water injection jet technology. The tools were applied in the punching process up to 50,000 strokes in order to analyse the cutting performance and tool wear. With regard to a highly wear resistant tool for punching, a combination of the abrasive water injection jet preparation routine and a CVD diamond coating are under further investigation and first insights are presented additionally.

Analysis of the Process and Results of High-Pressure Abrasive Water Jet Multilayer Cutting of Electrical Steel.

Electrical steels are magnetically soft materials and are widely used in the electrical industry for the construction of power transformer cores, distribution transformers, current transformers, and voltage transformers. An important parameter of electrical components, which determines the efficiency of devices, is energy loss during remagnetization. Energy losses are caused by eddy currents, hysteresis, and magnetic delay associated with the low quality of the cut edge after the cutting of steels, and material deformations and excessive stress concentration in the surrounding cutting zones. Common techniques for cutting electrical materials in industrial lines include mechanical cutting and laser cutting. Work has shown that mechanical cutting of electrical steel single layers results in the occurrence of large deformation zones, and in cutting processes with a high-pressure abrasive water jet (AWJ), significant uplifts of material and burrs at the bottom edges of sheets occur. The problem of increasing the cutting quality was solved through selecting the stream parameters for bundle cutting of electrical steels. It has been shown that in the process of cutting electrical sheet bundles, the height of burrs on the cut surface and the zone of plastic deformation are reduced. The work also presents comparison and analysis of characteristic features of the cut edge of electrical sheets obtained through high-pressure abrasive water jet and mechanical cutting processes. The influence of the type and processing parameters on the characteristic features of the material hysteresis loop was determined.

Experimental Research on the Use of a Selected Multi-Criteria Method for the Cutting of Titanium Alloy with an Abrasive Water Jet.

The use of selected multi-criteria decision methods for the optimization of cutting processes by abrasive water jet methods is increasingly being used in industrial processes. This is due to the complexity of the processes and the need to reduce operating costs. Process optimization methods are available to support organizational processes including the design phase, quality assurance, production automation, and many more. This article presents the current state of research on the water-abrasive cutting process and the use of multi-criteria methods in optimizing this process. This article presents a detailed methodological study of the VIKOR approach to optimization, indicating the applicability conditions, assumptions, and limitations on the example of high-pressure abrasive water jet cutting of elements made of titanium alloy utilizing HPX garnet abrasive. As a result of the research conducted, the best input parameters of the cutting process for abrasive flow rate, pressure, and the traverse speed of the cutting process were determined. The achieved result is consistent with the assumption that the most favorable output parameters are the highest cutting depth and the lowest level of roughness.

Investigation of heat transfer and damage characteristics of high pressure abrasive water jet impacting high temperature sandstone

ABSTRACT Efficient breaking of hard mineral rocks is an important prerequisite for deep metal mining. In order to study the rock breaking mechanism of abrasive water jet erosion of high-temperature hard rock in deep ground, the temperature deformation evolution law during the process of jet impact on rocks was simulated and experimentally studied. The results show that the distribution of jet pressure, jet velocity, and jet turbulent kinetic energy near the residence point of the jet impingement wall is generally high in the middle and low in the outside. The heat transfer distance r on the rock surface is approximately (1.5–2.0) times the nozzle diameter, and the heat transfer distance inside the rock is (1.0–1.5) times the nozzle diameter. The maximum heat flux density at the jet cooling wetting boundary can reach 450 W/mm2. Within 0–3 seconds of the erosion process, the average surface temperature sharply decreases and exhibits a downward trend of jet stagnation point radiating outward. The radius of jet cooling influence gradually increases. Due to the impact cooling effect, tensile stress is generated at the top of the rock sample, and the tensile stress in the lower part of the rock is converted into compressive stress. With the increase of jet pressure and treatment temperature, the area and range of erosion pits significantly increase, and there is a significant phenomenon of thermal cracking around the erosion pits. The research conclusion can provide new ideas and basis for hydraulic breaking of high-temperature hard rocks in deep ground.

Research on Multiphase Flow and Nozzle Wear in a High-Pressure Abrasive Water Jet Cutting Head

Research on the mixing process of gas–liquid–solid multiphase flow in a high-pressure abrasive water jet (HP-AWJ) is of great significance in improving the performance of water jet cutting. In this paper, the Euler method-VOF model, a computational fluid dynamics (CFD) simulation method, is used to solve the multiphase flow of air–water in an abrasive water jet (AWJ). The Euler–Lagrange method is further used to study the multiphase flow of abrasive particles. The method considers the shape factor of the particle, uses the Rosin–Rammler function, and defines an effective model for the particle-to-wall wear model. By solving the velocity of the continuous phase and particulate phase in the AWJ cutting head, the problem of nozzle wear caused by particles is studied. Finally, the exit velocity of the AWJ and particle wear are investigated by varying the model’s parameters. The results show that the double abrasive tube model effectively improved the problem of one-sided wear inside the nozzle, and the tangential velocity of the air affected the acceleration process of the abrasive inside the nozzle, with smaller abrasive velocity resulting in less wear on the model. Simultaneously, the effects of the abrasive inlet tube and mixing chamber size on abrasive exit velocity and nozzle wear are analyzed. The results obtained provide valuable guidance for addressing the multiphase flow mixing issues in the AWJ, improving the abrasive acceleration process and extending the nozzle’s lifetime.

Rail repair technology based on high-pressure abrasive water jet

Rail repair technology based on high-pressure abrasive water jet

Possibilities of Rock Processing with a High-Pressure Abrasive Waterjet with an Aspect Terms to Minimizing Energy Consumption.

The paper concerns the application a high-pressure abrasive waterjet (AWJ) for cutting the most commonly used rock materials such as granite, limestone, basalt and marble. Based on the analysis of the literature, the influence of parameters on the specific energy Ev, specific energy of cutting Er and specific energy of intersection Ea was determined. Experimental studies were carried out on a laboratory test stand in accordance with a five-level rotating experiment plan. The results of the research were subjected to statistical processing, obtaining regression equations. The influence of the pressure and diameter of the abrasive waterjet on the energy consumption of rock cutting was tested. The effect of the stream power, feed speed and pressure on the cutting depth with the AWJ was also determined. The data obtained made it possible to evaluate the machinability of the rocks as a function of the power of the jet. These analyses were supplemented with charts illustrating the influence of the most important technological parameter of the cutting process, which is the feed speed. The presented results provide answers to the energy and time requirements for efficient cutting with the AWJ of frequently used rock materials.

Desirability Function Analysis (DFA) in Multiple Responses Optimization of Abrasive Water Jet Cutting Process

This paper introduces optimization of machining parameters for high-pressure abrasive water jet cutting of Hardox 500 steel utilizing desirability function analysis (DFA). The tests were carried out according to the orthogonal matrix (Taguchi) L9. The control parameters of the process such as pressure, abrasive flow rate, and traverse speed was optimized under multi-response conditions namely cutting depth and surface roughness. The optimal set of control parameters was established on the basis of the composite desirability value obtained from desirability function analysis and the significance of these parameters was determined by analysis of variance (ANOVA). The effects show that optimal sets for high cutting depth and small surface roughness is high pressure, middle abrasive flow rate, and small traverse speed. A confirmation test was also leaded to validate the test results. Results of the research have shown that machining efficiency at keeping good level quality of cut surface can be improved this approach.

Efficient separation of coarse aggregates and cement mortar in the recycled concrete by water jet demolition

The disposal of construction wastes have become the current focus worldwide towards the sustainable development. The adhesion of the cement mortar onto the aggregates significantly impedes the properties of the recycled aggregate concrete. Towards improving the recyclability of construction wastes, this work presents a novel demolition technology using high-pressure abrasive water jet (HAWJ). The results showed that the micro-cracks on the fracture surfaces of the recycled concrete after HAWJ demolition mainly developed along the interfaces between the aggregates and the cement, thus resulting in the efficient separation of the coarse aggregates. The residual compressive strength of the recycled concrete could retain 71% after HAWJ demolition, demonstrating that the effect of HAWJ demolition was negligible. Therefore, it is reasonable to conclude that HAWJ demolition is a promising strategy to recycle the old buildings.

Smart Piezo-bonded carbon fibre/epoxy composite structure: experiments and finite element simulation

Smart sensors patched to composite structures assist in the prediction of the mechanical behaviour of the structures. The present paper used finite element modelling and experimental procedures to conduct a detailed study on the response of composite laminate bonded with smart piezoelectric material. Fibre reinforced epoxy composite laminate was fabricated using the vacuum assisted resin transfer method. Test coupons in accordance with ASTM standards were prepared using high-speed and high-pressure abrasive water jet cutting. The mechanical properties of the composites were obtained through material characterization and the material properties were incorporated into the Finite element model. The layer-wise strain rate was computed with the ANSYS® Composite Prep Post module. A finite element model of a composite with piezoelectric sensor patch was created in ANSYS® APDL and harmonic analysis was conducted to determine the optimal frequency range for the applied load. An attempt was made to measure the strain by affixing lead zirconate titanate to a carbon fibre reinforced polymer laminate for cantilever configuration, and the LabVIEW® VI software module was integrated with the NI myDAQ system to detect the corresponding voltage for the excited frequency. The values of the generated voltage through numerical simulations were verified and validated using experimental counterparts.

Experimental and numerical study on the indentation behavior of TBM disc cutter on hard-rock precutting kerfs by high-pressure abrasive water jet

Experimental and numerical study on the indentation behavior of TBM disc cutter on hard-rock precutting kerfs by high-pressure abrasive water jet

WASPAS Optimization in Advanced Manufacturing

This paper presented optimization of machining parameters for high pressure abrasive water jet (AWJ) cutting of Hardox 500 steel utilizing WASPAS approach. Weighted aggregated sum product assessment (WASPAS) method is explored as an effective MCDM tool while solving advanced manufacturing decision making problems. It is a unique combination of two well-known MCDM approaches, i.e. weighted sum model (WSM) and weighted product model (WPM).The tests were caried out according to the orthogonal matrix (Taguchi) L27. The control parameters of process such pressure, abrasive flow rate and traverse speed was optimized under multi-response conditions namely cutting depth and surface roughness. The optimal set of control parameters was established on the ground of the overall weighted criterium. Effects shows that optimal set for high cutting depth and small surface roughness are high pressure, high abrasive flow rate and small traverse speed. Results of research have shown that machining efficiency at keeping satisfactory level quality of cut surface can be improved this approach.

Investigation of the breaking manifestations of bedded shale impacted by a high-pressure abrasive water jet

Experiments on high-pressure abrasive water jet (AWJ) crushing shale were conducted with major consideration of bedding planes. The dynamic strain of the shale sample was obtained, and the shale-breaking manifestations and their influencing factors were analyzed by means of both qualitative and quantitative methods. The results indicate that the angle between the jet direction and bedding plane plays a dominant role in the rock-breaking manifestation, with a larger angle leading to a deep perforation hole in the shale and a small angle causing split-shaped breakage. The dynamic strain evolutions combined with the SEM images imply that the shale breaking manifestation of deep perforation holes is caused by the combined actions of huge compressive pressure and the edge chipping effect of abrasives, while the shale breaking manifestation of split-shaped breakage is contributed by huge compressive pressure and the water wedge effect. Additionally, the intermediate jet pressure and abrasive mass flow rate are found to be suitable for the formation of an excellent hole shape. The findings infer that the combination of a large angle, a suitable jet pressure and abrasive mass flow rate is demanded in the application of hydraulic AWJ perforation in shale gas exploitation, while a small angle with large jet pressure is demanded in the application of hydraulic AWJ slotting.

Permeability Enhancement Properties of High-Pressure Abrasive Water Jet Flushing and Its Application in a Soft Coal Seam

High-pressure abrasive water jet flushing (HPAWJF) is an effective method used to improve coal seam permeability. In this study, based on the theories of gas flow and coal deformation, a coupled gas-rock model is established to investigate realistic failure processes by introducing equations for the evolution of mesoscopic element damage along with coal mass deformation. Numerical simulation of the failure and pressure relief processes is carried out under different coal seam permeability and flushing length conditions. Distributions of the seepage and gas pressure fields of the realistic failure process are analyzed. The effects of flushing permeability enhancement in a soft coal seam on the gas drainage from boreholes are revealed by conducting a field experiment. Conclusions can be extracted that the gas pressure of the slotted soft coal seam is reduced and that the gas drainage volume is three times higher than that of a conventional borehole. Field tests demonstrate that the gas drainage effect of the soft coal seam is significantly improved and that tunneling speed is nearly doubled. The results obtained from this study can provide guidance to gas drainage in soft coal seams regarding the theory and practice application of the HPAWJF method.

Influence of water pressure and abrasive materials nature on the duration of the high-pressure abrasive water jet cutting in building structures

Purpose. Improving the efficiency of abrasive water jet cutting by choosing rational process parameters and abrasive material.
 Methods. Full-scale tests within the program of a full-factor experiment on cutting a high-pressure barrel into building structures, statistical data processing.
 Findings. Experimental data on the time of the high-pressure cutting barrel into building structures made of various materials have been obtained.
 Application field of research. The research results can be used by fire rescue units in emergency response.

The analysis of high-pressure water jet cutting of thick aluminium alloy 6061-T651 from a statistical perspective

The main context in which abrasive water cutting is used is the reduction of thermal deformation induced by thermal (plasma arc PAC, oxyfuel OFC, laser) of electrothermal (electroerosion EDM) cutting methods. Although it is not the cheapest or time-efficient technique it can be used on a wide variety of metallic and non-metallic materials. Among other benefits are the lack of burrs, high precision and improved surface finish, low setup time and stress-free cutting. This leads to no secondary processing required in many other applications. Depending on the material hardness the cutting thickness can reach up to 300 [mm]. The present study proposes an analysis of high-pressure abrasive water jet cutting of a 19 [mm] thick plate. The aluminium alloy used in this study was Al-6061-T651. This alloy is being used especially in the aeronautics industry due to is excellent welding properties. The experiments were conducted using multiple input and output factors. The design of experiments (DOE) takes into account input factors and offers models for responses. The study was organised according to response surface methodology, with an I-optimal design type and a quadratic design model. The input factors were: cutting pressure, standoff distance, programmed quality of the cut. The responses analysed were: entrance (Iw) and exit (Ow) width of cut, and taper angle (α). An ANOVA analysis was performed for each response. This interpretation implies the significance (p-value) that the input factors have on the variation of the responses. For Iw and Ow a reduced 2FI model was proposed, while for θ a linear model was suggested. The p-value obtained for each response is smaller than 0.0001, which classifies the models as significant. The ANOVA fit statistics determine the R-squared error between 0.964 and 0.995, meaning that the responses are well defined by the input value variations. This high confidence in the results leads to accurate mathematical models.

High pressure abrasive water jet for excavation purpose: a tridimensional approach for cutting strategy

Abstract High pressure abrasive water jets (HPAWJ) are an emergent excavation technology. Despite being used for several applications since the nineteenth century, it is only in recent decades that this excavation purpose has been considered. This is the result of evolution in high pressure pump technology and parameter investigation. Special highlight should be given to optimization works which improve knowledge about the main parameters. However, studies usually neglect the importance of HPAWJ cutting strategies, and only consider bidimensional approaches as options for nozzle movement. This article analyzes and proposes an operational cycle based on a tridimensional approach for HPAWJ. Higher removal rates and lower energetic consumption are expected in comparison with traditional strategies.

Investigation of diagnostic possibilities of the state cutting process of steel with high-pressure abrasive water jet

The article presents the application of vibration measurement of the cutting head for the diagnostics of the state of the cutting process with high-pressure water jet. Data acquisition was performed when cutting wedge-shaped samples of S355J2H steel. The recorded signal was analyzed appropriately. In the summary part, conclusions from the research were drawn.

CFD research on particle movement and nozzle wear in the abrasive water jet cutting head

Particle velocity and movement in the high-pressure abrasive water jet (AWJ) heading are significant jet properties which deserve a better understanding for improving AWJ machining performance. In this paper, particle acceleration and movement trajectory in the jet field within AWJ cutting head were conducted based on the Euler-Lagrange approach and the discrete particle model (DPM) from a computational fluid dynamics (CFD) simulation study. The particle inlet position, particle inlet angle, and converge angle of focus tube were taken into consideration in the physical model. The models were then assessed qualitatively and quantitatively by previous experiment data. The results indicated that a particle inlet located at a high position could increase particles’ exiting velocity and decrease nozzle wear. A steeper abrasive feed angle would improve the particle acceleration process and reduce radial velocity, resulting in less nozzle weight loss. The effects of converging part angle were analyzed as well. The obtained results would improve the machine efficiency of the workpiece, extend nozzle lifetime, and guide the future design of AWJ nozzle.