The design parameters drill pattern, standoff distance, loading. Create rectangular, triangular and equilateral patterns create vertical or inclined holes on flat, inclined or undulating surfaces. Following, is a list of typical considerations that. While most mines use a standard blast pattern and charge per blasthole, based on a single rock factor for the entire bench or blast region, information derived from the mwd parameters can improve the blast design by providing more accurate rock properties for each individual blasthole. Study of a continuous drill and blast tunneling concept 4. Forged bits made up of single length of drill steel and are available at several shapes. The delays are fixed from the middle to the ends as shown in the fig. Introduction the bureau of mines has been conducting field studies of explosive blast ing in rock for a number of years. The advanced blast firing sequence design functionality in geovia surpac 6. Mosher, in gold ore processing second edition, 2016. The university of queensland bachelor of engineering. Thus, for a blaster, valuable tool is the file of blast reports that he builds as he gains experience. When an explosive charge is detonated, chemical reaction occur which, very rapidly changes the solid or liquid explosive mass.
Borderguard allows blast designers to designate a virtual boundary within which the drill is intended to operate. Characterizing the rock mass the keys to characterizing the rock mass are a good geologist and a good blasting driller. It is practiced most often in mining, quarrying and civil engineering such as dam, tunnel or road construction. The first step in designing the cut is to design the blasting such that the blast effects are controlled to suit the requirements of the operation. Blast pattern the plan view of the drill holes as laid out for blasting. An existing polygon object is required to generate a drillhole pattern. The presence of open caves or large vugs can also influence blast design.
Delay intervals between rows less than 6 ms per of burden. Surveying and setup drilling charging blasting ventilation scaling mucking. Basic timing design select the time between holes in a row based on one third to one half the time between rows. The center blast hole in the first row blasts first, followed by the blast holes connected to the.
Drill monitoring systems and the integration with drill and. Carlson releases precision 3d drill and blast design software. Delay intervals between holes in a row less than 3 ms per meter of spacing are not recommended due to air blast and fragmentation considerations. Selection of a drilling pattern should include consideration of the method of blast initiation to be used delay or simultaneous. Blast parameter variations were simulated and compared on a 200 m x 50 m standard blast.
Dec 07, 2015 blasting contractors should lay out the drill pattern based on a surveyed profile of the face. At a minimum, a profile survey should be done after drilling and before loading so that the proper explosive load can be determined for each blast hole based on the survey and drill log. Preblast survey face points, crest, toe, top of coal and drill surface points were imported to the software. The available techniques for drill and blast design in underground mining were analyzed. The advantages and disadvantages of the widely used blast hole patterns, types of cuts, and explosives are estimated. Because of widely varying properties of rock, geologic structure, and explosives, design of a blasting program requires field testing. Basic drilling cycle for drill and blast drifting and tunneling. Drill and blast design course is a oneday session designed for experienced users of surpac with an interest to follow a blast design from start to finish. This chapter provides the fundamental concepts of blast design. Drill monitoring systems and the integration with drill. Audit drill patterns against blast hole distribution and location constraints. Clearing the toe, and therefore contributing to a smoother floor, is a major asset to improve. Exel drilling understands that good blast design is vital to ensuring costefficient operations and output. These rules provide a first estimate in the absence of any better data.
Apr 05, 2017 the advanced blast firing sequence design functionality in geovia surpac 6. Drill pattern manager construct hole templates with design parameters such as fixed or variable collar or toe spacing, angle changes and variable toe horizons. Drilling and blasting is the controlled use of explosives and other methods such as gas pressure blasting pyrotechnics, to break rock for excavation. Import an asdrilled pattern from csv or drl file and compare with the design to make sure all blastholes are drilled within a specified tolerance of the design blastholes, and. Blast design using measurement while drilling parameters. Create reports showing pattern layout, graphic pdf maps of the design with labels and transparent textures in 3d. Several factors must be taken into account when designing the drilling pattern. Drill and blast allows for quick and easy blast pattern layouts, with real time 3d editing and instant feedback, says director of the carlson mining division, grant wenker. Stateoftheart software and computer technology provides a vehicle for a new approach to designing and verification of blasting patterns and training of.
A new perimeter control blast design concept for underground. Tradeoffs frequently must be made when designing the best blast for a given geologic situation. By avoiding time consuming tasks such as scanlines and rock sample collection for laboratory tests, mwd techniques can not only save time but also improve the reliability of the blast design by providing the drill and blast engineer with the information specially. Blasting patterns free download as powerpoint presentation. Reduction in powder factor by 37% reduction in blasting cost per 20m bench by 21%. In mining operations, the manager of the mine or the principal employer at the mine would be required to hold copies or originals.
Blast plan preparation, including mining operations guide. Wedge cut pattern or diagonal blasting pattern wedge cut pattern. The insitu ore properties, drill blast pattern, and properties of the explosive govern the size distribution of rocks produced from a blast and the energy efficiency of the blast. Measurement while drilling mwd techniques can provide a useful tool to aid drill and blast engineers in open cut mining. Pdf blasting design for tunnels find, read and cite all the research you need on researchgate.
Way more information than you ever wanted on how to fell a tree. This pattern as shown in the fig, is adopted in hard and medium hard rocks. Weekly or monthly safety meetings that include the blast crew, drill. Blasthole are drilled at an angle to the face in a uniform wedge formation so that the. Geovia surpac drill and blast design 1 day the surpac. Blast hole diameter d in mm15 burden b 25 to 40 x d spacing s 1. The basic patterns of drill holes employed in opencast mines are square pattern staggered or triangular pattern single row blasting pattern multi blasting pattern wedge cut pattern diagonal blasting pattern square pattern. We use our tailored blast fragmentation model and unique smarttag tm ore tracking system to assess the optimum blast conditions required for each particular ore type.
Blast design software blasting pattern software blast. In addition, a minimum of two 2 red led flashing lights shall be placed at the pattern entry to demarcate the sleeping pattern to ensure anyone approaching the pattern at night is aware of the associated hazard. Changes to blast design following the introduction of the memu truck the size of the shothole diameter increased from 95mm to 110mm. The size reduction process starts with mining, and the degree of fracturing and breakage achieved in drill and blast is an important factor in comminution circuit performance. When the vugs extended the full depth of the round, drill pattern and timing sequence were. The result of rock blasting is often known as a rock cut. The advantages and disadvantages of the widely used blasthole patterns, types of cuts, and explosives are estimated. The undeniable strength of the tool is the pattern designed contrary to the traditional approach at the end of the round where successful blasting is at its most critical stage. Drilling patterns selection of drilling pattern varies with the type and size of the drills used, depth of hole, kind of rock, quantity, rapidity of the.
Drill patterns and explosive loads can be modified, and within drilling equipment limits, holesize can be changed. The flow on affects of such a significant pattern expansion has led to a number of benefits as detailed below. Adjust to a rectangular pattern of the same total cubic yards. Determine approximate square pattern from table 1 of blasters guide, or multiply the number ob powder factor 9. Mechanism of rock breakage while release of explosives energy upon detonation and other relevant points are discussed below. Set blast timing for holes in various patterns and sequences and animate the resultant blast. Blast design figure 82 staggered pattern figure 83 sing figure 81 square or rectangular pattern. When the vugs extended the full depth of the round, drill pattern and timing sequence were modified to take advantage of the opening.
Designing blast patterns using empirical formulas office of. Drill patterns and explosive loads can be modified, and within drilling. Apr 21, 2012 drill bits types of drill bits detachable bits removable from the drill when required. Share what you know and love through presentations, infographics, documents and more. The overall number of shotholes reduced when blasting the same size of rock mass. Drill bits types of drill bits detachable bits removable from the drill when required. Construct hole templates with design parameters such as fixed or variable collar or toe spacing, angle changes and variable toe horizons. Criteria such as distance from the highwall face, or comparison of design vs. Blast design the best use of explosives is made when a blast produces a clean break, giving good fragmentation, while avoiding excessive flyrock. With todays monitors and guidance systems, operators can view in 3d not only the holes as they are being drilled, but an entire pattern. Rock blasting consists of drilling holes in a rock mass at depths, in. If the blastholes are drilled as a staggered pattern on an equilateral triangular grid, the optimum distribution of the. The basic patterns of drill holes employed in opencast mines are. Generates blast plan and according to the delay pattern structure, simulation.
Correspondingly, the selected mining process is a consideration in development of the comminution circuit design. This provides hole burden calculus and optimization of hole. Design changes are recommended for those qarries where problems are occurring. Blasting contractors should lay out the drill pattern based on a surveyed profile of the face.
This helps ensure current holes are not drilled into a hole from the previous bench. In the fluorspar mines in illinois, 1 to 2 m 3 to 6 ft wide vugs commonly occurred in heading round faces. Not only do these provide evidence of the quality of his work, but they also. This pattern can also be called as multi row pattern. The results from the initial design, were compared to. Descriptive notes 2ype of rpeoi and incluoie dates final report, aug. Improved production rates and consequent cost reduction in digging, hauling, crushing, or moving rock are. Blast designer software blades calculates blast plan parameters, explosives charge distribution, initiation timing and sequence, results in terms of rock breakage and fragment size distribution. Drilling and blasting powerpoint 2003 linkedin slideshare. Round dimensions are usually preset, and designers must often accept the limitations that come with using existing drilling equipment drilling equipment. Guide to blast plan preparation, including mining operations page 5 of 14 for two years after the use of the explosive. Reducing the cost of drill and blast through blast design. The result of rock blasting is often known as a rock cut drilling and blasting currently utilizes many different varieties of.
Various drilling patterns have been developed for blasting solid rock faces, such as. Multiple row patterns are of three types, staggered, rectangular, and square, and generally require the use of delay caps or other delay devicesstaggered pattern. The basic patterns of drill holes employed in opencast. Blast plan a written procedure that details the methods and manner by which a project blaster will comply with pertinent laws, rules, regulations, and contract documents. Pdf automation of drill and blast design researchgate. The success of achieving these goals depends significantly on good blast design. Knowledge of mathematical formulas will provide ease in designing a blast that will be safe as well as effective. The blast pattern will be demarcated according to the current surface blasting safety procedures 2. Explosive selection, blast design, and delay pattern must consider the specific rock mass being blasted. Despite some limitations, many other design elements can be adjusted to improve round design.
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