Delay intervals between rows less than 6 ms per of burden. Blast design using measurement while drilling parameters. Round dimensions are usually preset, and designers must often accept the limitations that come with using existing drilling equipment drilling equipment. 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. The design parameters drill pattern, standoff distance, loading.
Borderguard allows blast designers to designate a virtual boundary within which the drill is intended to operate. Because of widely varying properties of rock, geologic structure, and explosives, design of a blasting program requires field testing. The new blast design concept applies the understanding of radial damage that is caused by the buffer hole column charge. Weekly or monthly safety meetings that include the blast crew, drill. The blast pattern will be demarcated according to the current surface blasting safety procedures 2.
When an explosive charge is detonated, chemical reaction occur which, very rapidly changes the solid or liquid explosive mass. The advantages and disadvantages of the widely used blast hole patterns, types of cuts, and explosives are estimated. The success of achieving these goals depends significantly on good blast design. 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. Drill monitoring systems and the integration with drill and. Audit drill patterns against blast hole distribution and location constraints.
The university of queensland bachelor of engineering thesis. Create reports showing pattern layout, graphic pdf maps of the design with labels and transparent textures in 3d. Despite some limitations, many other design elements can be adjusted to improve round design. Drilling and blasting is the controlled use of explosives and other methods such as gas pressure blasting pyrotechnics, to break rock for excavation. With todays monitors and guidance systems, operators can view in 3d not only the holes as. Guide to blast plan preparation, including mining operations page 5 of 14 for two years after the use of the explosive. An existing polygon object is required to generate a drillhole pattern. Following, is a list of typical considerations that. Drilling pattern design in tunneling and drifting is based. Blast hole diameter d in mm15 burden b 25 to 40 x d spacing s 1.
Buffer hole radial damage is defined by a practical damage limit applied to the rock lying between the buffer holes and the perimeter. Pdf blasting design for tunnels find, read and cite all the research you need on researchgate. Generates blast plan and according to the delay pattern structure, simulation. Changes to blast design following the introduction of the memu truck the size of the shothole diameter increased from 95mm to 110mm. Various drilling patterns have been developed for blasting solid rock faces, such as. Rock blasting consists of drilling holes in a rock mass at depths, in. Improved production rates and consequent cost reduction in digging, hauling, crushing, or moving rock are. Study of a continuous drill and blast tunneling concept 4.
Pdf elements of drill and blast design and 3d visualization in. When the vugs extended the full depth of the round, drill pattern and timing sequence were. With todays monitors and guidance systems, operators can view in 3d not only the holes as they are being drilled, but an entire pattern. Adjust to a rectangular pattern of the same total cubic yards. 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 blast holes and loading them with ex plosives. Construct hole templates with design parameters such as fixed or variable collar or toe spacing, angle changes and variable toe horizons. 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. 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. Mechanism of rock breakage while release of explosives energy upon detonation and other relevant points are discussed below. Mosher, in gold ore processing second edition, 2016.
Reducing the cost of drill and blast through blast design. Knowledge of mathematical formulas will provide ease in designing a blast that will be safe as well as effective. This helps ensure current holes are not drilled into a hole from the previous bench. Drill patterns and explosive loads can be modified, and within drilling. This pattern can also be called as multi row pattern. Multiple row patterns are of three types, staggered, rectangular, and square, and generally require the use of delay caps or other delay devicesstaggered pattern. Rapidly generate drill patterns using predefined hole templates then manually adjust as required to final design. The presence of open caves or large vugs can also influence blast design. These rules provide a first estimate in the absence of any better data. The result of rock blasting is often known as a rock cut. 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. Carlson releases precision 3d drill and blast design software. The advanced blast firing sequence design functionality in geovia surpac 6.
Correspondingly, the selected mining process is a consideration in development of the comminution circuit design. Several factors must be taken into account when designing the drilling pattern. Pdf automation of drill and blast design researchgate. Blast design the best use of explosives is made when a blast produces a clean break, giving good fragmentation, while avoiding excessive flyrock. Share what you know and love through presentations, infographics, documents and more. Design changes are recommended for those qarries where problems are occurring.
Criteria such as distance from the highwall face, or comparison of design vs. Basic drilling cycle for drill and blast drifting and tunneling. Blast parameter variations were simulated and compared on a 200 m x 50 m standard blast. Drill pattern manager construct hole templates with design parameters such as fixed or variable collar or toe spacing, angle changes and variable toe horizons. 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. The drilling pattern ensures the distribution of the explosive in the rock and desired blasting result.
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. Reduction in powder factor by 37% reduction in blasting cost per 20m bench by 21%. Basic timing design select the time between holes in a row based on one third to one half the time between rows. This provides hole burden calculus and optimization of hole. When the vugs extended the full depth of the round, drill pattern and timing sequence were modified to take advantage of the opening. Apr 21, 2012 drill bits types of drill bits detachable bits removable from the drill when required. The university of queensland bachelor of engineering. The delays are fixed from the middle to the ends as shown in the fig.
Measurement while drilling mwd techniques can provide a useful tool to aid drill and blast engineers in open cut mining. In mining operations, the manager of the mine or the principal employer at the mine would be required to hold copies or originals. Designing blast patterns using empirical formulas office of. Not only do these provide evidence of the quality of his work, but they also. 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.
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 figure 82 staggered pattern figure 83 sing figure 81 square or rectangular pattern. Descriptive notes 2ype of rpeoi and incluoie dates final report, aug. Preblast survey face points, crest, toe, top of coal and drill surface points were imported to the software. Blasting patterns free download as powerpoint presentation. The flow on affects of such a significant pattern expansion has led to a number of benefits as detailed below. Pipeinhole sounds an alarm and can lock the propel. Apr 05, 2017 the advanced blast firing sequence design functionality in geovia surpac 6. Clearing the toe, and therefore contributing to a smoother floor, is a major asset to improve.
Drill patterns and explosive loads can be modified, and within drilling equipment limits, holesize can be changed. 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. The results from the initial design, were compared to. Drilling and blasting powerpoint 2003 linkedin slideshare. The available techniques for drill and blast design in underground mining were analyzed.
Way more information than you ever wanted on how to fell a tree. Forged bits made up of single length of drill steel and are available at several shapes. It is practiced most often in mining, quarrying and civil engineering such as dam, tunnel or road construction. This chapter provides the fundamental concepts of blast design. 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. 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. In the fluorspar mines in illinois, 1 to 2 m 3 to 6 ft wide vugs commonly occurred in heading round faces. A new perimeter control blast design concept for underground. Blast design software blasting pattern software blast. Drill monitoring systems and the integration with drill.
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. The advantages and disadvantages of the widely used blasthole patterns, types of cuts, and explosives are estimated. Drill bits types of drill bits detachable bits removable from the drill when required. The basic patterns of drill holes employed in opencast.
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 pattern the plan view of the drill holes as laid out for blasting. 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. Create rectangular, triangular and equilateral patterns create vertical or inclined holes on flat, inclined or undulating surfaces. This pattern as shown in the fig, is adopted in hard and medium hard rocks. Introduction the bureau of mines has been conducting field studies of explosive blast ing in rock for a number of years. The center blast hole in the first row blasts first, followed by the blast holes connected to the. Dec 07, 2015 blasting contractors should lay out the drill pattern based on a surveyed profile of the face. Set blast timing for holes in various patterns and sequences and animate the resultant blast. Blasting contractors should lay out the drill pattern based on a surveyed profile of the face. 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.
Tradeoffs frequently must be made when designing the best blast for a given geologic situation. Explosive selection, blast design, and delay pattern must consider the specific rock mass being blasted. Surveying and setup drilling charging blasting ventilation scaling mucking. The overall number of shotholes reduced when blasting the same size of rock mass.
Exel drilling understands that good blast design is vital to ensuring costefficient operations and output. Stateoftheart software and computer technology provides a vehicle for a new approach to designing and verification of blasting patterns and training of. 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. Blast plan preparation, including mining operations guide.
12 311 181 305 88 640 123 1456 1179 597 1024 246 99 1100 926 744 753 1057 1248 375 387 1291 886 89 1455 1414 1351 655 533 1074