The pipe processing department at Epiroc faced a major capacity crunch about seven years ago. Robotic handling of exploration drilling pipes expedites product processing.
Mining in South Africa was once the main driving force behind the history and development of Africa’s most advanced and richest economy. Its decline is illustrated by the fact that gold is currently only the fourth biggest selling commodity in South Africa right now, with coal, platinum group metals (PGMs) and iron ore all bringing in more money than gold. There are many reasons for mining’s decline, both in terms of South Africa’s GDP and its position as being regarded as the number one mining country in the world a couple of decades ago, and we don’t have to elaborate.
Epiroc introduced a Yaskawa Motoman automatic handling cell to process their pipes they supply to the mining exploration drilling industry
The introduction of the Yaskawa Motoman automatic handling cell has resulted in the company now processing pipe at a fraction of the time as compared to manual handling. Alignment challenges when coupling pipes are now non-existent because of the consistency of the tolerances and accuracy of the cell and the company is saving heaps of costly floor space because the robot turns the pipes in the air where there are no obstructions
The dominant sentiment towards South African mining over the past decade has been overwhelmingly negative, with phrases like “a sunset industry” bandied about. This was largely informed by South Africa’s larger mining houses facing multiple challenges, including ageing infrastructure, the inherent difficulties of deep-level mining, escalating costs and falling commodity prices. Many mines have closed due to the unsustainable losses they incurred.
The situation was worsened by the fact that meaningful exploration had not taken place for decades, despite South Africa having such rich mineral endowments. Mining exploration is widely credited with being a catalyst for future economic growth and business opportunities. With the right support from the government, investors and the miners themselves, the South African mining sector could again materially boost South Africa’s economic growth as it once did in the past.
However, mining still contributes large numbers to the South African economy and will continue to do so as long as there are reserves of the various commodities mined, to exploit.
Manufacturing Manager Anthony Jansen Van Vuuren and shopfloor team leader Ephraen Letsoalo
Epiroc processes various sizes of pipe for the mining exploration drilling industry
There are many engineering and manufacturing companies that feed off the mining industry, as well as the numerous that are employed in the industry. One such company is the division of Epiroc that is a manufacturer and distributor of drilling consumables for mining exploration.
Jason Lotter established Renegade Drilling Supplies in 2005. It was Lotter’s second venture into the mining industry, having previously had a manufacturing company that he sold to multinational Atlas Copco, a global industrial supplier based in Sweden, in 2003.
“Atlas Copco decided to disinvest from the exploration drilling supplies industry in South Africa. This gave me the opportunity to get back into the mining exploration industry, supplying consumables such as drill bits and reamer heads as well as manufacture the pipes and pipes used for exploration drilling for core extraction.”
“Exploration diamond drilling is used in the mining industry to probe the contents of known ore deposits and potential sites. By withdrawing a small diameter core of rock from the ore body, geologists can analyse the core by chemical assay and conduct petrologic, structural and mineralogical studies of the rock at the surface with reduced environmental impact and lower costs,” explained Lotter.
“Before the invention of the portable diamond drill, most mineral prospecting was limited to finding outcrops at the surface and hand digging. Early drilling opened up many new areas for mineral mining, and was related to a boom in mineral exploration in remote locations.”
Core extraction
“Merely advancing the drill by rotary action (and washing) causes a core to be extracted inside the barrel. However, at a depth of perhaps 300m, there must be a way to retrieve the core and take it to the surface. Constantly withdrawing the entire heavy drill pipe is impractical, so methods were developed to pull up the core inside the barrel. If the rock would always be solid granite, and the core would always break at the drill bit, then it would be a simple matter to stop the drilling, and lower a simple grabbing device by a wire and pull up the core. Unfortunately, many applications require an undisturbed core in fractured rock, which calls for elaborate wire-line devices.”
Pipe sizes
“There are five major pipe sizes typically used in the mining exploration drilling industry. Larger pipes produce larger diameter rock cores and require more drill power to drive them. The choice of pipe size is a trade-off between the rock core diameter desired and the depth that can be drilled with a particular drilling rig motor.”
“Key dimensions used for exploration drilling all over the world are pipes with an outside diameter from 40mm to 140mm. Other sizes are available on request. The most common that we manufacture is a 100 OD that weighs about 55kg.”
Epiroc has designed and manufactured its own pipe handling spanner
Epiroc supplies various other group manufactured consumables for the mining exploration drilling industry
“Lengths vary according to client but we do process pipe up to six metres in length, which could weigh 120kg. Depending on the angle of the drill hole, exploration can take place between two and 2.5 kilometres here in South Africa because South Africa’s deposits lie at these distances underground. This involves many pipes being used.”
Processing of pipes
“The material we use is generally cold drawn pipes supplied by Arcelor Mittal South Africa in grades EN19 and EN9, both high-quality, high-tensile steel usually supplied readily machinable in ‘T’ condition, giving good ductility and shock resisting properties combined with resistance to wear.”
“Awareness of the hazards associated with press brakes and stamping presses have improved dramatically. The same cannot be said for the tube and pipe industry. Operational hazards similar to those in general fabricating can be found in the manufacturing of tube and pipe, yet safeguarding devices are not always in use, or they are bypassed and circumvented. For those working in an environment where tube and pipe is produced or fabricated, the dangers have not been made so apparent, and operators are regularly required to put themselves in harm’s way, relying on company-established administrative safety measures and their own skills to prevent injury.”
Epiroc manufactures its own head assemblies for the drill pipes
Between 65 and 88 components can make up a head assembly, all of which are manufactured by Epiroc
“Unlike flat metal, pipe and tube are round and they don’t have burrs and sharp edges. When straight, their shape allows gravity, a very affordable energy source, to be used regularly to move them around the shop. On the downside, these parts are tough to stack and, once formed, become a handling and storage problem.”
“Tube and pipe operators tend to work with long lengths. During the forming process, operators are exposed to parts whipping around on a bending machine. As parts grow in size, so does the working area. Unsuspecting workers that are not prevented from entering the working area during a job could be in extreme danger of being hit by the tube or pipe as it is being formed. Additionally, each piece must be placed into a clamp, exposing the operator to a pinch point every time.”
“As in any manufacturing scenario, safety enhancements can turn an operation with frequent exposure to potential harm into an operation with significantly less exposure to these hazards. The round shape of tube and pipe makes it an easy to move material, but it can also present a danger if the right controls are not being used. It’s just a matter of making the right choices.”
Adding a Yaskawa robotic cell
“We had these issues and decided to address them. There were a few other motivating factors besides health and safety that led us to add a Yaskawa robotic driven material handling cell – productivity and floor space.”
“Besides cutting to length where required because the pipes are generally supplied in six metre lengths, the only other operation we are doing is threading on each end of the pipe. In some instances, slotting and marking is required.”
The CNC machining department. Epiroc are looking to replace a few older machines with more modern CNC machines that can perform more than one operation when processing material
“We have implemented many training programmes for the operators and to give you an example a component that used to take one hour and 43 minutes to machine now only takes 27 minutes. It was not about the CNC machine improving times. It was more about improving the skills of the operators.”
“If you consider the weight of each pipe it needs two staff to position the pipe in the Haas CNC lathe that we use. You also need the floor space to turn the pipe around because both ends are threaded and of course during this handling procedure you introduce all sorts of other unwanted variables.”
“The challenge to Yaskawa South Africa was to come up with an automated handling solution, while also taking into account that not every pipe is straight.”
“Their engineers introduced a Yaskawa Motoman ES165-DX200 robot that feeds, removes and turns pipe for two Haas CNC lathes. Feeding tables, steadies and safety devices to protect the boundaries were added.”
“The result is we are processing pipe at a fraction of the time as compared to manual handling, and alignment challenges when coupling pipes are now non-existent because of the consistency of the tolerances and accuracy. And of course we are saving heaps of costly floor space because the robot turns the pipes in the air where there are no obstructions.”
“It has been a very satisfying solution to our challenge and as a result we are busy designing a second robotic material handling cell that will introduce even more features and reduce production times, as compared to our first installation.”
Job shop machining
The company is more than a pipe processing business. Besides the two Haas CNC lathes that process the pipes the company also has three other Haas CNC lathes and three Haas CNC mills to process numerous components that make up the other drilling consumables, such as drill rods, in-the-hole tools, couplings, adaptors, recovery tools and diamond drill bits that the company markets.
A pre-machined component with the same component that has been final machined and coated
The material that Epiroc uses is generally cold drawn pipes supplied by Arcelor Mittal South Africa in grades EN19 and EN9, both high-quality, high-tensile steel usually supplied readily machineable in ‘T’ condition, giving good ductility and shock resisting properties combined with resistance to wear
Close to 1 500 different components are machined in the CNC machining department. For example, the company manufactures its own drill head that comprises between 65 and 88 different components to be machined and then assembled.
“This department has also had major productivity improvements,” said Manufacturing Manager Anthony Jansen Van Vuuren.
“We have implemented many training programmes for the operators and to give you an example a component that used to take one hour and 43 minutes to machine now only takes 27 minutes. It was not about the CNC machine improving times. It was more about improving the skills of the operators.”
Epiroc uses an Amada HA 250 band saw to cut-to-length pipes before processing them on the Yaskawa Motoman automatic handling cell
The company processes numerous components that make up the other drilling consumables, such as drill rods, in-the-hole tools, couplings, adaptors, recovery tools and diamond drill bits
“However, we are in the future going to look for more time savings when we introduce the latest CNC machines. Our machines are seven years and older and a bit tired. We plan to sell four of them and purchase two modern CNC machines that incorporates the latest technology.”
“We like to think of this department as a job shop because we do machining work for other companies besides fulfilling our own requirements. We run the machines on Mastercam and we have Solidworks in our design department so we can offer design and re-engineering services.”
Joining the Epiroc Group
At the end of 2017 it was announced that Atlas Copco had purchased Renegade Drilling Supplies, effective January 2018, Lotter’s second venture into the mining industry. Atlas Copco was then subsequently split into two entities and Lotter’s company joined the new group Epiroc.
“The business is now part of the Rock Drilling Tools division in Epiroc. The acquisition expanded our exposure to other Group companies and further established our regional footprint for manufacturing of mining exploration consumables,” concluded Lotter.
For further details contact Epiroc on TEL: 011 793 6365 or visit www.epiroc.com
