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Study on the long-hole raising technique using one blast ...

A scheme of multiple deck blasting based on vertical crater retreat (VCR) drop-raising method was designed for an abandoned cavity with 30-m cover. The lower 12-m cover was first blasted to ...

Underground Mine Timbering & Support

Caps in the stopes (a method incorrectly classified as square-set mining, but more correctly known as stull and fill) do not need squeeze headings; plain headings as shown in Figure 3b are sufficient. Depending on the thickness …

Vertical Crater Retreat | PDF | Mining | Science

Vertical crater retreat (VCR) mining is a method originally developed by the Canadian. mining company INCO. Today, VCR is an established mining method used by mines all over the world that. have competent, steeply dipping ore and host rock. VCR is based on the crater blasting technique in which powerful explosive charges are.

(PDF) Shrinkage stoping and Vertical Crater Retreat stoping

8. VCR - V ertic al Cra ter R etr eat. V ert ical Crater Retreat (VCR) or V ertical Retreat Stoping: configuration method in stopes where drilling large diameter is used to. detonate horizontal ...

Optimising Raising Development Using the Drop Raise …

Optimising Raising Development Using the Drop Raise Method at DOZ Mine PT Freeport Indonesia. The DOZ underground mine at PT Freeport Indonesia is a copper and gold mine in Indonesia with current ore production of 42 000 tpd. Because of the mine expansion into the West DOZ more ventilation raises are needed to create a safe and healthy work place.

(PDF) Underground mining Methods - ResearchGate

Underground Mining Methods. Soft rock Mining Methods. Blast mining. Shortwall mining. Coal Skimming (or Sink and Fl oat) method. Hard rock Mining Methods. Stoping. 1) Room and pillar. 2) Bench and ...

Mining operations and mobile equipment selection …

Mining operations and mobile equipment selection audit – guide Page 7 of 22 2.4 Operating controls are suitably and legibly identified. Intent: To ensure operators can readily identify controls and actions to safely operate the equipment. Personnel: N/A Method: View a sample of mobile equipment. Refer to AS 2359.5 – Symbols for operator ...

Raise bored slot raises: A modern mining technique

level stoping mining method. The average stope height is 25 meters but can be as high as 40 meters. The original long-hole open stoping method required 21 drill holes for opening a drop raise in each stope, using the same conventional long-hole rigs as that were used for drilling

Study on the long-hole raising technique using one blast ...

VCR method has been an established mining method being practiced in various mines all over the world. 8 An offshoot of this mining method is the VCR drop-raising technique that employs the same spherical crater charge technology as VCR method.9, 10 This technique has vastly improved raise blasting safety because top loading no longer requires ...

Types of Underground Mining Method Comparison

C, Fig. 2, is a wide raise or raise stope, which is one method of opening an overhand stope, and E is a drift stope, which is a term used in the Lake Superior copper mines and means a wide and high drift as a start for the …

Sub-level open stoping - QueensMineDesignWiki

Slot Raising. In conventional sublevel stoping where vertical rings or rows of holes are blasted it is necessary to have a slot to allow for rock expansion. It can be done as a slot raise driven by conventional raising methods, by raise …

Study on the raising technique using one blast based on ...

A scheme of multiple deck blasting based on vertical crater retreat (VCR) drop-raising method was designed for an abandoned cavity with 30-m cover. The lower 12-m …

Drop Raising In Underground Mines: Methods For …

Drop Raising in Underground Mines: Methods for Underground Mining | Original Article. Ramlakhan Meena*, in Journal of Advances and Scholarly Researches in Allied Education | Multidisciplinary Academic Research

Study on the long-hole raising technique using one blast ...

method. VCR method has been an established mining method being practiced in various mines all over the world [8]. An offshoot of this mining method is the VCR drop-raising technique that employs the same spherical crater charge technology as VCR method [9-10]. This technique has vastly

Drop Raising In Underground Mines: Methods For …

Drop Raising in Underground Mines: Methods for Underground Mining | Original Article Ramlakhan Meena*, in Journal of Advances and Scholarly Researches in Allied Education | Multidisciplinary Academic Research

Ventilation - QueensMineDesignWiki

Transverse stoping is similar to the VCR mining method in which it is necessary to provide ventilation for the top sill of the stope and the bottom sill of the stope where muck is picked up. Both of these sills are driven by crosscutting …

MECHANISED MINE DEVELOPMENT UTILISING ROCK …

Drop raising is commonly used world-wide in the development of rock and ventilation passes over a length of generally up to 60m in the vertical mode and around 15m in an almost flat mode (Refer graph 1 and 2 – Inclination and length matrix). Drop raising offers a safe method of excavation at relatively economic cost.

DROP RAISING METHOD | Mine Portal Blog

MINING METHODS & GEOLOGY ... CLICK ME TO DOWNLOAD PDF NOTES ON DROP RAISING METHOD. NOTES CONTAIN DETAILS ABOUT DROP RAISING METHOD. 24-04-2020 0 0. Comments. No Comments . × View Comments. Close. Mine Portal is the favourite choice of thousands of mining professional aspirants for online exam preparation. ...

underground mining methods drop raising

Drop Raising in Mining (VCR) Method copper mining India 201919&ensp·&enspD rop Raising in Mining (VCR) Methods of Stopes ( Extraction of Ore). Hindustan Copper Limited has addressed the complex 'raising' operation in mining and developed and implemented Drop Raising techniques at 80 meters intervals which improved safety and led to faster and ...

Drop Raising Method | PDF | Mining | Drilling

Drop Raising Method - Free download as PDF File (.pdf), Text File (.txt) or view presentation slides online. Drop raising method

Techniques of inverse drop raise blasting and slot drilling

A scheme of multiple deck blasting based on vertical crater retreat (VCR) drop-raising method was designed for an abandoned cavity with 30 …

Drop raising in underground mines - SlideShare

This is a method of making Raise between two adjacent levels by blasting. The concept of blasting is 'Vertical Crater Retreat'.

Rockpasses: a guide to excavation methodology

method unacceptable. ˜ Raise climber: site preparation and installation time makes this method inappropriate for shorter holes. ˜ Conventional drop raising: this method is applicable, but the extra cost and the interruption of the raise process counts against it. ˜ Invert drop raising is totally applicable due to set-up

Raise boring slots: a modern mining technique

Raise boring slots: a modern mining technique Raise boring has commonly been employed at different stages of mine construction for decades, most frequently as a means of drilling shafts, raises and ore chutes – but seldom (despite the endless possibilities) as a production method…until now, writes Jarko Salo, the managing director of

Improving Productivity in Pillar Blasting HZL ... - Orica

raising is done by drop raise VCR. The raise is the first void created against which the subsequent rings are fired, the productivity of the stope depends on the turnaround time of the raise. A typical stope of 35 m (114.8 ft) - 40 m (131.2 ft) would take around 15-20 blast cycles to develop the raise. This method has

Description of mining methods (step by step)

Primary Mining Method Cut-and-Fill mining method. Information. Development in the ore of the upper and lower drift. The distance between the levels is 91 m (300 ft). Development of the service raise. Excavation of the stope. Two options: the …