Meter-high waves, storms with high wind speeds, plus oil, mud and heavy rainfall: living and working on an oil platform is not only uncomfortable, it is also dangerous. Drill rods are driven up from the borehole and are disassembled and reassembled under high pressure by oil-smeared men. Lots of manual work under time pressure, in the dirt and with a high risk of injury. But that could all be over soon. The Norwegian company Robotic Drilling Systems has developed a robotic system for automating the drilling processes on the platform after many years of research and development work. Energy chains from igus ensure reliable energy supply under extreme conditions.

In industry, more and more processes are being automated in order to achieve higher cycle rates, relieve people of heavy work and save costs at the same time. This trend can also be observed on oil rigs: The start-up company RDS Robotic Drilling Systems AS in Stavanger, Norway – a center of the European oil industry – develops robots with the aim of completely automating the drilling work on oil rigs.

 This goal is ambitious for several reasons. The robotic systems work under difficult conditions and must therefore be insensitive to salt water, corrosion, mechanical stress and sometimes extreme temperatures. In addition, the work processes on an oil rig are so complex that up to 100 axes have to be coordinated when handling the drill rods. Last but not least, energy, media and signals must be reliably routed to the robot’s grippers.

Energy and signal supply via rotation module and energy chain

The seventh axis of the ‘ Drillfloor Robot’ is a heavy-duty linear system on which the entire robot and its load move. This presented the designers with the challenge of designing the power and signal supply to be flexible enough – and that in extremely tight spaces. In addition, there are high explosion protection requirements in this area. The energy supply for the linear movement of the seventh axis was relatively easy to implement: Light plastic energy chains have proven themselves in numerous similar applications and enable cables for energy, data and media to be routed at the same time. On the other hand, the task of making the energy and signal supply on the axis of rotation of the robot foot move accordingly was trickier.

Complete solution for complex tasks – engineering included

This task is solved with a rotary module from igus. It is an energy chain which is used lying on its side and uses a “back bend radius” (RBR). This means that the chain links are moved in both directions, unlike traditional linear travel . The cables and hoses are guided securely in the chain with ‘locking dividers’ and the chain is inserted in a round guide channel.

In the case of the RDS robot, this rotary module was integrated into the robot housing, which required real ‘tinkering’ and professional engineering due to the very limited installation space. This task was carried out at igus by a team from the ‘Project Engineering’ department. The result is a complete solution in a special robot installation, in which, in addition to the rotary module, the chainflex cables from igus are also used, which are certified for potentially explosive areas and also according to NEK 606. The cables were developed from the ground up for mobile applications and impress with their long service life even under extreme conditions. igus guarantees a shelf life of 36 months for all cables in the range and has already certified 403 cables from the range in accordance with the DNV GL offshore regulations.

The energy chains are delivered to Stavanger ready-made as ‘ readychain ‘ systems including plugs. This not only simplifies assembly. It also ensures that all connections and connecting elements meet the special requirements of electrical explosion protection. Corrosion resistance is also often very important, particularly in offshore applications. The maintenance-free plastic energy chains can be used here without restrictions. Depending on customer requirements, igus also takes over all work steps from planning to complete assembly on site – even on the high seas, because the service employees are certified to work on oil drilling platforms.

Mobility also in the vertical

igus components are also used on the other automation units of the unmanned oil drilling process. Both on the ‘ Electric Roughneck ‘ and the ‘Pipe Handler’ run energy chains – a total of 25 pieces. They are arranged on the masts, ie on the vertical axes of the handling systems with which the ‘stands’ are taken from the store and fed to the central robot. Here, too, freedom from maintenance, insensitivity to seawater and mechanical stresses as well as explosion protection and offshore approvals were decisive for the selection. Jimmy Bostrom , Chief Operating Officer of Robotic Drilling Systems: “It is important for us to obtain components for the robots from a single source and, if possible, to be ready for installation. The systems should also be as maintenance-free as possible. igus can guarantee that.”

The robotic system developed by RDS is suitable for installation on new oil drilling platforms, but also for ‘ retrofitting ‘. It creates new rules of the game for assessing the economics of exploration projects – an important factor in view of the low oil prices. For this reason, the new development met with great interest right from the start – and led, among other things, to well-known drilling companies investing in RDS. Also the jury of the vector initiated by igus awards convinced the application and awarded the system the golden vector 2016. After comprehensive tests, a first practical installation was put into operation on an oil drilling platform in Norway in September 2015. The entire industry is closely following the project that will make work on oil rigs faster, cheaper and, above all, safer.