O'Connor, D & Sertic, T 2019, 'Development of a remote control rock bolting system for narrow seam hard rock mines', in W Joughin (ed.), Deep Mining 2019: Proceedings of the Ninth International Conference on Deep and High Stress Mining
, The Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 231-244, https://doi.org/10.36487/ACG_rep/1952_18_O_Connor
An estimated 90 percent of South Africa’s gold-bearing reefs are less than 1 m thick Joughin (1976). A large mineral resource therefore lies in seams that are becoming increasingly uneconomic to extract because of the grade dilution caused by raising the mining height to suit currently available mechanized mining equipment Harper (2008). A similar situation applies to platinum resources.
Historically in SA, mining of these narrow seams has been carried out by labour intensive methods, with little equipment beyond hand-operated rock drills. However, the arduous and hazardous work environment is becoming increasingly unattractive to both the workforce and mine operators. Globally, major mining companies are striving to increase safety by removing workers from the immediate vicinity of the operations and increasing productivity by better integration of the phases of the regular mining cycle to reduce cycle times Lynch and White (2013). Attaining both objectives requires going beyond mechanization to high degrees of automation and/or remote control of equipment.
These factors present a challenge to South African mine operators and their equipment suppliers as mechanization of the narrow seam, hard rock mining environment has proven difficult with scant success Pickering and Ebner (2006), and Harper (2008).
This paper describes the development of a semi-automated, remote controlled rock bolting system for hard rock mines with a mining height of between 0.9 m and 1.2 m (ULP Project). The rock bolting system required development of fully mechanized, remote controlled rock bolting rig, novel rock bolts and a pumpable, fast-acting resin grout to secure the bolts.
The introduction of systematic rock bolting has resulted in a decrease in rock-related accidents, but the many manual operations required in drill-steel and bolt handling in confined spaces and close proximity to high-powered equipment, has led to increased injuries (particularly hand injuries) to the rock bolting operators Makusha (2015). Remote-control equipment has the potential to mitigate such injuries.
The rock bolter is one component of an equipment suite enabling full mechanization of rock breaking by blasting, clearing broken rock and rock support. Development started in 2012 and the bolting rig has been operating on a platinum mine since 2017. Deployment of further equipment suites is planned for 2019.
ArcelorMittal 2017. Material Test Certificates, Arcelor-Mittal, Vereeniging, South Africa, 2017.
bray, p. and johnsson, A. 2019. Case study: LKAB Malmberget, self-drilling anchors and pumpable resin. Paper submitted for publication at DeepMine 2019, SAIMM, Johannesburg, 2019.
MAKUSHA, G., 2015. Personal communication.
HARPER, G.S. 2008. Nederburg Miner. Presented at Narrow Vein and Reef Symposium, SAIMM, Johannesburg 2008. pp. 2 – 4.
HARPER, G.S. 2008. Nederburg Miner. Presented at Narrow Vein and Reef Symposium, SAIMM, Johannesburg 2008. Pg 4.
LYNCH, M. AND WHITE, B. 2013. Brave new world of autonomous mining systems. World Gold Conference Brisbane, AusIMM, Melbourne, 2013. Pg 1.
MAEPA, T. AND ZVARIVADZA, T. 2017. Installation of resin-grouted rockbolts in hard-rock mining: challenges and solutions for improved safety. JSAIMM, vol 117, April 2017, pg 331.
MINOVA-MAI, 2017. Self-drilling systems product catalogue, Minova-MAI, Austria, 2017, pp 3-10.
MINOVA-MAI, 2017. Self-drilling systems product catalogue, Minova-MAI, Austria, 2017, pp 16.
MINOVA CARBOTECH, 2017. Carbothix 150709 Technical Data Sheet. Minova Carbotech, Essen, 2017.
JOUGHIN, N.C. 1976. Potential for mechanization in gold mines. JSAIMM, Johannesburg, January 1976.
O’CONNOR, D. 2014. Effect of atmospheric pressure on resin capsule rigidity. Presented at SANIRE Coalfields Branch Symposium, November 2014.
O’CONNOR, D. 2013. Interim report on rotary drilling trials in norite. Minova Africa (Pty) Ltd internal report, Johannesburg, 2013.
PICKERING, R. AND EBNER, B. 2001. Hard rock cutting and development of a continuous mining machine for narrow platinum reefs. 6th International Symposium on mine mechanisation and automation. SAIMM, Johannesburg, 2001. Pg 1.
RICHTER, A. 2005. A method for embedding rock anchors. Australian Patent Office, Application No. 2005297473 B2, 2005.
RSC EKUSASA. Product datasheet, RSC Ekusasa Mining, Johannesburg, 2007. pg 3.