Blasting System Research Articles

Effect of a Photolithography Polymer Mask's Dynamic Viscoelasticity on Microchannel Cross-Sectional Shapes of Glass Processed by Micropowder Blasting.

In this study, a micropowder blasting system with varying processing temperatures was proposed to control the cross-sectional shape of a channel processed on a glass substrate. Based on an analysis of the processing temperature-dependence of the dynamic viscoelastic properties of a commercial mask material for micropowder blasting, a processing temperature control system that can be installed in a micropowder blasting machine was designed. The erosion of the mask during micropowder blasting depended on the loss tangent in dynamic viscoelasticity, and showed a maximum value at a processing temperature of 100 °C. Moreover, we confirmed that the maximum decrease in the width of the processed microchannel was 30 µm (12%) by mask erosion, and this change was large compared with the maximum change in the thickness of the eroded mask. These results clarified that varying the processing temperature using a mask could control the cross-section of the processed line pattern profile on glass, and a small-width channel was realized at a processing temperature of 109 °C.

Optimal model-based control for automated robotized abrasive blasting system

In robotic abrasive blasting operations, achieving the required surface roughness and cleanliness relies heavily on manually pre-set operational parameters. These parameters, such as stand-off distance, blasting angle, inlet air pressure, abrasive flow rate, and particle size, are set based on operator experience. However, given that optimal values for these parameters vary depending on specific blasting conditions and surface requirements, the pre-set values often fail to deliver both the desired surface quality and productivity. To address these challenges, we propose a solution employing a set of proxy models and a model predictive control system to achieve optimal operational outputs. For energy efficiency and productivity maximization, we utilize computational fluid dynamics with a multiphase flow solver to determine the optimal stand-off and offset distances, thus controlling the blasting nozzle effectively. Additionally, we build a data-driven model to obtain the optimal reference set point of air pressure at the sensor location based on the desired surface roughness. Moreover, we develop a dynamic process model to link the inlet air pressure and abrasive flow rate to the air pressure at the sensor location, which facilitates the development of a model-based control system. By applying this comprehensive approach, we evaluate and optimize the control and operational parameters to achieve the desired surface roughness and productivity targets. To validate the effectiveness of our newly developed control system and models, extensive tests are conducted both virtually (in silico) and on-site. The results confirm the stability and accuracy of the control system. In on-site reliability tests, the automated blasting system successfully delivers the desired surface roughness with a relative error of less than 5 % and a remarkable 30–50 % improvement in productivity. Overall, our innovative control system and models offer a reliable and efficient solution for robotic abrasive blasting, ensuring consistent surface quality and productivity enhancements.

Research on the Optimization of Open-Pit Mine Cast Blasting Parameters Based on the Optimal Economy of Dragline Stripping Technology

As the key technology of high-step stripping and blasting engineering, throwing blasting will be the development trend of the production optimization and benefit maximization of the open-pit mine in the future. In order to break with the research idea of optimizing the cast blasting effect by improving the effective throwing rate for a long period of time, maximizing the economic benefit of the subsequent dragline stripping technology and stabilizing the engineering connection, this paper takes the Heidaigou open-pit mine as the research object. Through data acquisition, analysis, and data fusion of the heaped-up bulk characteristics, the heaped-up bulk profile can be obtained to characterize the cast blasting effect. Secondly, the key factors influencing the cast blasting effect are determined based on the gray relational degree theory. Then, the black box principle of the system control theory is adopted as the guiding principle of the blasting optimization. Based on the production data of field cast blasting, the dynamic change law between the controllable variables of system input and the observable variables of system feedback in the black box system are studied and explored without consideration of the internal structure or the energy transformation relationship of the cast blasting system. Finally, the optimal blasting parameter combination under different working conditions is obtained. If the research results are successfully applied, it is expected that the dragline stripping technology cost of the Heidaigou open-pit mine can be reduced by 5~10%, and the results can also provide new ideas and new ways of optimizing the design of cast blasting.

Analysis of pressure surges under various flow patterns in the tunnel of an underwater rock plug blasting system using different transition process models

Abstract The pressure surge at the moment of blasting seriously threatens the safety of pipeline structures and other buildings. This article established two numerical simulation models of the hydraulic transition process and water–air two-phase flow based on the one-dimensional transient flow theory and considering the actual flow characteristics of water and air. The hydraulic characteristics and blasting parameters of the blasting system were studied under two different conditions of the tunnel with and without the pressure flow. The observed parameters of an actual blasting engineering prototype verified the accuracy of the mathematical model. The maximum pressure of pressure blasting was 2.55 times as high as hydrostatic pressure. The maximum pressure of non-pressure blasting was 1.77 times as high as hydrostatic pressure. Pressure blasting impact was 2.17 times greater than nonpressure blasting. Discrepancies between actual and simulated data for gushing and overflow heights ranged from 9 to 14%. The model can provide a reference for blasting engineering on the simulation calculation of hydraulic characteristics such as impact pressure, overflow time, and overflow of the underwater rock plug blasting system.

STUDY OF OCCUPATIONAL SAFETY AND HEALTH ON BLASTING PROCESS IN ANDESITE STONE MINING AREA WITH HIRAC METHOD IN CV. ARTHA AGUNG BERSAMA, HULU GURUNG SUB-DISTRICT, KAPUAS HULU REGENCY

CV. Artha Agung Bersama is an andesite mining company that uses a blasting system. This mining activity can harm workers if they do not apply good K3 management in blasting activities. One of the hazards of blasting activity is flying rock. For this reason, it is necessary to identify potential hazards, assess the level of accident risk, and recommend risk control efforts. The method in this study is the HIRAC (hazard identification risk assessment and control) method. This activity has five potential hazards: broken drum straps, worker negligence, explosive sounds, fly rock, and workers walking in a hurry in locations with a lot of gravel. There are five risks of accidents from potential hazards: being hit by a drum, scratched hands, pinched fingers forming a critical cover, slipping, exposure to diesel fuel, hearing loss, and being hit by a rock. Of the five hazard risks, three risks are included in the priority one category, namely: scratched hands, pinched fingers forming key covers, slipping, exposure to diesel fuel, and being hit by rocks. One risk is included in priority category three: being hit by a drum. One risk category is very high, namely being hit by a rock. The recommended risk control hierarchy for blasting activities is engineering control, administration, and personal protective equipment.

Research on the Fracture Properties and Mechanism of Carbon Dioxide Blasting Based on Rock-like Materials

Liquid carbon dioxide blasting technology has a wide range of applications and is characterized by sound fracturing effects, low vibration hazards, and high safety. In order to investigate the characteristics and mechanism of CO2 phase change rock breaking, liquid CO2 blasting tests on rock-like specimens were carried out in this paper. The results show that 130 MPa is the threshold value at which a CO2 blasting system moves from dynamic tensile stress damage to dynamic pressure stress damage. When blasting pressures of 100 MPa and 70 MPa are used, the lumpiness ratio of the fragments does not change much as the strength of the rock changes, so a suitable blasting pressure should be chosen to improve the blasting effect. Under the impact of blast stress and high-pressure gas flow, cracks develop to form a rough failure surface.

Annotation and evaluation of base editing outcomes in multiple cell types using CRISPRbase.

CRISPR-Cas base editing (BE) system is a powerful tool to expand the scope and efficiency of genome editing with single-nucleotide resolution. The editing efficiency, product purity, and off-target effect differ among various BE systems. Herein, we developed CRISPRbase (http://crisprbase.maolab.org), by integrating 1 252 935 records of base editing outcomes in more than 50 cell types from 17 species. CRISPRbase helps to evaluate the putative editing precision of different BE systems by integrating multiple annotations, functional predictions and a blasting system for single-guide RNA sequences. We systematically assessed the editing window, editing efficiency and product purity of various BE systems. Intensive efforts were focused on increasing the editing efficiency and product purity of base editors since the byproduct could be detrimental in certain applications. Remarkably, more than half of cancer-related off-target mutations were non-synonymous and extremely damaging to protein functions in most common tumor types. Luckily, most of these cancer-related mutations were passenger mutations (4840/5703, 84.87%) rather than cancer driver mutations (863/5703, 15.13%), indicating a weak effect of off-target mutations on carcinogenesis. In summary, CRISPRbase is a powerful and convenient tool to study the outcomes of different base editors and help researchers choose appropriate BE designs for functional studies.

Обоснование эффективности взрывных работ с использованием электронных систем в сравнении с неэлектрическими средствами инициирования

Carrying out large-scale blasting using non-electric primers in surface mining is concerned with a number of deficiencies, one of which being the error in borehole and surface delay times. As a consequence, the design blasting system is compromised, the face blasting rates are affected, and the rock mass fragmentation quality goes down. Due to their advantage in the triggering accuracy, the electronic blasting systems ensure absolute control over the execution of large-scale blasting, reduce the negative impact of blasting operations on residential areas near the surface mine and improve the quality of rock mass fragmentation. Electronic blasting systems enable the development of new ways to execute blasting, for example, though selecting the face blasting rates, which in turn increases the rock mass fragmentation quality and reduces dilution. The paper presents comparative indicators of bias in the nominal delay times of various non-electric primers and electronic blasting systems, discusses the components and designs of electronic detonators, and provides a number of advantages of the electronic systems in conditioning of the the preparation of blasted rock. A conclusion is made that blasting with electronic detonators and the use of their advantages will help to reduce the specific consumption of explosives and the scope of drilling operations due to larger blasthole patterns.

Assessment of energy consumption, carbon emissions and cost metrics under hybrid MQL-Dry ice blasting system: A novel cleaner production technology for manufacturing sectors

Modern industries are seeking innovative and clean cooling techniques in the machining domain to reduce the cost and environmental impact of manufacturing. To diminish the environmental impact of machining, cryogenic and minimum quantity lubrication (MQL) are recent known cooling/lubrication techniques to determine a perfect alternative to mineral-based emulsion cooling. The cryogenic has superior cooling capabilities and poor lubrication and MQL is vice versa. In this endeavor, a new hybrid MQL-dry ice blasting lubri-cooling technology is proposed in machining as eco-benign technology to investigate sustainability as well as machinability metrics in the milling of AISI-52100. The findings have shown that cutting speed and cooling/lubrication showed the most substantial effect on machinability and sustainability metrics. The experimental findings showed that the cutting speed has more significant effect on specific energy consumption, carbon emission, and machining cost. At highest level of cutting speed (300 m/min), processing time, specific energy consumption, carbon emission and surface roughness was 2.6%, 2.3%, 2.35%, and 22.6% less under hybrid dry ice blasting compared to MQL medium. The shares of the standby time in total energy consumption, carbon emission, and total cost are noticed to be dominant. The hybrid dry ice blasting shared a small fraction of the total cost compared to MQL, and dry ice blasting.

A novel low-pressure hybrid dry ice blasting system for improving the tribological and machining characteristics of AISI-52100 tool steel

Hybrid minimum quantity lubrication and compressed carbon dioxide (MQL + CO2) lubri-coolant can play a crucial role in advancing machinability as well as sustainability. However, it is also the fact that the high-pressure throttling of CO2 produces fog and hinders the low-pressure MQL mist to touch the cutting zone adequately. Therefore, a low-pressure novel hybrid MQL-dry ice blasting lubri-coolant technology is anticipated to improve the machinability by providing the cooling and lubrication simultaneously in milling AISI-52100. This low-pressure hybrid dry ice blasting not only reduces an abundance of smog to reduce the cutting zone visibility, but the dry ice grains also behave as carriers to bring MQL-mist to the cutting zone perfectly. In this proposed study, the surface roughness, residual stresses, cutting temperature, surface hardness, tool wear, and cutting forces are measured by varying the cutting speed (75-300 m/min) and feed per tooth (0.04–0.12 mm/z) under hybrid MQL-dry ice blasting lubri-cooling condition in milling AISI52100 tool steel. The results of this study highlighted that as the cutting speed raised from 100 m/min to 300 m/min, an increase in cutting temperature was 22 % at a constant feed per tooth of 0.08 mm/z. Similarly, the decrease in surface roughness was 42 %, tool life reduced to 57 %, surface hardness increased to 9 %, and across-the-feed surface hardness increased to 58 % by the increase of cutting speed from 75 to 300 m/min and constant feed per tooth of 0.08 mm/z. The proof-of-the-concept study showed the machinability advancement under hybrid lubri-cooling technology due to precise penetration of MQL mist and dry ice grains into the cutting zone in terms of ease in chip evacuation, excellent lubrication, and cutting heat dissipation by sublimation of dry ice.

Оценка качества капсюлей-детонаторов (с пиротехническим замедлением) неэлектрических систем инициирования по времени их срабатывания

Blasting operations in surface and underground mining are characterized by the need to protect the environment from harmful effects of the detonation products of explosives, the fly rock zone, the seismic manifestations of the blast, as well as airborne shock waves. Non-electric blasting systems by various manufacturers are used in Russia, but all of them have certain advantages and disadvantages. It can be stated that the blasting caps of the applied blasting system do not always correctly execute the firing times specified by their manufacturer. Mismatches of the actual firing times from the rated ones might be so great that the applied blasting systems sometimes produce disturbances in the order of charge firing, which, in turn, may cause detonation failure in the boreholes. Studies have shown that in order to reduce the risk of detonation failures, regardless of their causes, it is recommended to initiate the borehole at two points with placing the second primer in the upper part of the borehole, or using extended priming charges.

Pillar recovery using new wireless blasting technology: a case study in Vazante mine, Brazil

The application of explosives has never been considered as a major influencing factor during either the designing of a mine or the selection of the mining method. However, this has changed with the launch of WebGenTM wireless blasting system, which allowed underground mines to exploit their orebody applying methods previously not possible due to limitations imposed by the use of wired detonators. The wireless blasting system is based on magnetic induction communication, and its signal is capable of overcoming hundreds of meters through rock, water, and air, to reach individual primers in the blastholes without any physical connection.A noble application of wireless detonators is being used in Vazante mine, Brazil, an underground zinc mine where ore pillars are left in the mined stope to secure stability and minimize dilution by limiting the hydraulic radius. The recovery of these pillars is financially desirable but involves extra time and costs associated with scaling, backfilling, reinstalling infrastructure, accessing areas previously blasted (less stable), drilling, charging with explosives, and subsequently, firing and mucking out the blasted material with expected high dilution. Applying 100% wireless detonators made it possible to safely preload the pillar together with production blasts before losing access to the area, a method named Temporary Rib Pillar (TRP). After all the stope is mined and the pillar accomplished its objectives, the primers are initiated without neither the need for the extra cycles described previously, nor the need to re-enter the area. Thus, it was possible to reduce the exposure of people and equipment, reduce operational cycles, and increase ore recovery, directly contributing to anticipate the ore production while guaranteeing the safety of the teams involved.

Effects of Automated Grit Blasting on Roughness and Thickness Loss of Reaction-Bonded Silicon Carbide

Thermally sprayed coatings improve component lifespan and protect the underlying substrate in high temperature and corrosive environments. The coating adhesion is one of the most important properties with respect to coating performance. Before coating, surfaces are typically cleaned and roughened via manual grit blasting to promote mechanical interlocking of the coating with substrate. With recent interest in implementing ceramics and ceramic composites in the hot section of advanced gas turbine engines, there is a need to better understand how to prepare these nonmetal and composite materials before being coated. In this study, an automated grit blasting system was utilized to observe the effects of parameters such as blast pressure, angle, and nozzle traverse speed on multiple surface roughness parameters of reaction-bonded silicon carbide (rb SiC). The effect of these parameters on the substrate thickness loss during grit blasting was also analyzed. Blast pressure had the largest effect on surface roughness, as well as the highest linear correlation with roughness parameters. The automated robotic system allowed for the controlled study of traverse speeds higher than that typically used for grit blasting (≤ 350 mm/s). Increasing nozzle traverse speed was found to greatly reduce material loss with minimal effect on surface roughness.

Optimal sampling plan for an unreliable multistage production system subject to competing and propagating random shifts

Sampling plans play an important role in monitoring production systems and reducing quality- and maintenance-related costs. Existing sampling plans usually focus on one assignable cause. However, multiple assignable causes may occur, especially for a multistage production system, and the resulting process shift may propagate downstream. This article addresses the problem of finding the optimal sampling plan for an unreliable multistage production system subject to competing and propagating random quality shifts. In particular, a serial production system with two unreliable machines that produce a product at a fixed production rate is studied. It is assumed that both machines are subject to random quality shifts with increased nonconforming rates and can suddenly fail with increasing failure rates. A sampling plan is implemented at the end of the production line to determine whether the system has shifted or not. If a process shift is detected, a necessary maintenance action will be initiated. The optimal sample size, sampling interval, and acceptance threshold are determined by minimizing the long-run cost rate subject to the constraints on average time to signal a true alarm, effective production rate, and system availability. A numerical example on an automatic shot blasting and painting system is provided to illustrate the application of the proposed sampling plan and the effects of key parameters and system constraints on the optimal sampling plan. Moreover, the proposed model shows better performance for various cases than an alternative model that ignores shift propagation.

Operational parameters impact on the performance of dry-ice blasting nozzle

Carbon dioxide due to its chemical and physical properties can be successfully used in the wide range of surface cleaning an pre-treatment applications. One of the main carbon dioxide cleaning application is the dry-ice blasting, which seems to be a promising method of industrial devices cleaning. In the method the solid carbon dioxide particles supplied by the pressurized dry air are speed up to supersonic velocities in the convergent-divergent nozzle to finally reach the cleaning surface. Then via cooling and sublimation, causing in the rapid volume growth the pollution is crashed and removed with the air flow. Main cleaning mechanisms of dry-ice blasting are described in the paper. The crucial part of the system is the nozzle. The article covers the operational parameters impact on the nozzle performance. The authors present the methodology allowing the dry-ice blasting system assessment and provided the bench tests of the convergent-divergent supersonic nozzle in the field of nozzle’s efficiency, cleaning speed and operational costs. Impact of inlet air pressure, nozzle outlet-surface distance, cleaning angle, surface type and crushing sieve implementation was determined and analysed.

Optimizing Replaced Nozzle Diameter of Abrasive Blasting Systems Using Experiment Technique Design

The blasting technique has been broadly utilized to prepare new surfaces for painting, engraving, etc., in industry. In fact, the minimization of the cleaning cost system is essential. However, the knowledge of this technique in terms of optimization has been poor so far. The aim of this study is to find the optimum replaced boron carbide nozzle diameter for the abrasive blasting system. The basis of the study is to find the replaced nozzle diameter to minimize the cost of the blasting system. Seven main parameters are adopted for examining their influences on the response and the optimum replaced nozzle diameter. The design of experiment (DOE) technique is utilized by using Minitab@19. The results reveal that the initial nozzle diameter has the strongest impact on the optimum replaced nozzle diameter. Furthermore, the proposed regression model has been found to be entirely insistent to the experiments. The utilization of this model can provide an effective way to simplify the calculation of the optimum initial nozzle diameter for boron carbide.

ANALISIS BREAK EVEN POINT HASIL PELEDAKAN BATU GRANIT PADA UNIT PELEDAKAN PT ADITYA BUANA INTER DI KECAMATAN MERAWANG KABUPATEN BANGKA

The process of mining granite in PT Aditya Buana Inter is mined with an open pit (quarry)system. The granite blasting system at PT Aditya Buana Inter consisted of 5 blasting and with 386holes of explosive holes obtained, the total institutional volume was 199.996 m3 (BCM) and the totalvolume of blasting was 13001, 7 m3 (BCM) of the target company of 16,000 m3 (BCM) / month. Drillingand blasting activities to produce blasting volumes of course there are factors that influence theseactivities. Factors that influence drilling and blasting activities affect the costs incurred and the volumeof blasting results produced, the factors that influence these activities include: weather, frontconditions, equipment damage, less optimal blasting geometry measurements. The activity is certainlynot inseparable from the costs that must be incurred by PT Aditya Buana Inter both fixed costs andvariable costs. The total costs incurred by PT Aditya Buana Inter on September 2, 2018 to October4, 2018 are Rp 352,677,200.00 which includes fixed costs of Rp 170,616,020.00 and variable costs(variable costs) of Rp 182,061,000.00, and variable costs per m3 the volume of blasting yield is Rp14,003 /m3. Break even points obtained from calculations for units are 812,468 m3 and in rupiah Rp181,992,901.00. PT Aditya Buana Inter income from the sale of split stone is Rp 472,846,080.00obtained from the sales volume of 2110.92 m3 with a selling price of Rp 224,000 /m3, the profit (L)obtained is Rp 90,610,140.00. Calculation of Break Even Point analysis can determine the minimumamount of volume of rock from the blasting that will be produced and to find out the condition of thecompany not making a profit and also not losing.

Positive Phase Pressure Function and Pressure Attenuation Characteristic of a Liquid Carbon Dioxide Blasting System

As environmental requirements become more stringent, the liquid carbon dioxide blasting system is one of the non-explosive blasting technologies that, with low tensile stress energy, will replace the chemical explosive blasting technology, and the impact pressure characteristic of high-pressure fluid is a crucial factor in the process of rock breaking. To further investigate the impact and pressure attenuation characteristics of high-pressure fluid during the phase transition of liquid carbon dioxide blasting system, the pressure curves of high-pressure fluid in liquid carbon dioxide blasting systems at different distances were measured in the laboratory. Based on the mechanism analysis of phase transition kinetics, the initial jet velocity of the four experiments was calculated, and the rationality of results was verified by the Bernoulli equation. The general expression of the positive phase pressure–time function was proposed, and the idealized impact pressure curve can be divided into five stages. The impact pressure field of the liquid carbon dioxide blasting system can be divided into three areas at different distances: the explosive jet impact zone, the jet edge zone and the shock wave action zone, and the pressure–contrast distance fitting equation of the liquid carbon dioxide blasting system were obtained.

Automatic abrasive blasting system for large diameter pipe bends

Abrasive blasting is an important surface treatment process. Aiming at overcoming the shortage of the manual abrasive blasting process for large diameter pipe bends, T-pipes and gas collecting tubes, this paper presents the study of automatic abrasive blasting for large diameter pipe bends. According to the requirement of blasting process of large diameter pipe bend, the 5-DOF orthogonal coordinate abrasive blasting mechanism is constructed. Due to the massive dust and serious wear, the seal and protective measures of the mechanism are fully considered. In order to maintain a reliable operation of abrasive blasting system in severe environment, an automatic control system based on PLC is designed. In order to keep a specific angle between the sand-blasting gun and the workpiece surface, which can improve the working efficiency, the surface tracking control model was constructed based on the infrared distance measuring sensors. In order to improve the measurement accuracy of the sensors, the second order linear fitting method based on the least square method was used to calibrate the infrared range sensors. The experimental results indicate that the proposed automatic abrasive blasting system has significance on improving sand blasting quality, working efficiency and environment as well as reducing labour costs.

Automatic abrasive blasting system for large diameter pipe bends

Abrasive blasting is an important surface treatment process. Aiming at overcoming the shortage of the manual abrasive blasting process for large diameter pipe bends, T-pipes and gas collecting tubes, this paper presents the study of automatic abrasive blasting for large diameter pipe bends. According to the requirement of blasting process of large diameter pipe bend, the 5-DOF orthogonal coordinate abrasive blasting mechanism is constructed. Due to the massive dust and serious wear, the seal and protective measures of the mechanism are fully considered. In order to maintain a reliable operation of abrasive blasting system in severe environment, an automatic control system based on PLC is designed. In order to keep a specific angle between the sand-blasting gun and the workpiece surface, which can improve the working efficiency, the surface tracking control model was constructed based on the infrared distance measuring sensors. In order to improve the measurement accuracy of the sensors, the second order linear fitting method based on the least square method was used to calibrate the infrared range sensors. The experimental results indicate that the proposed automatic abrasive blasting system has significance on improving sand blasting quality, working efficiency and environment as well as reducing labour costs.