by Steven Berg, VP Operations
For years the service rig industry performed work on live wells with the help of rig-assisted snubbing units. The end result was that the job could be done safely, efficiently, and in a cost effective manner for the operators.
Why are these services necessary? Our geologically sensitive formations can get swollen and lose production from a well each time it is killed. The kill fluids, pumped at a medium pressure, fill the voids in the fractures and plug off the flow of gas or oil. This can render a multimillion dollar well almost useless in a production sense.
In a series of incidents fueled by high gas prices there were a few tragedies in western Canada that showed the vulnerable nature of having derrickhands in the tubing board of a service rig while rig-assist snubbing units were helping convey the pipe out of the well without killing it.
Swift reaction by the service rig community brought a decision to ban derrickhands from tubing boards during rig-assist snubbing operations. This was inserted into IRP 15, and letters were issued to all trade associations notifying them of the position of the CAODC companies.
So what’s changed? Since then, IRP 15 has gone through two re-writes and has introduced safety measures that were not in place in 2005. The introduction of interlocking controls to prevent pipe from being pulled against closed BOPs or possibly having no control of pipe, the use of dual barrier plugs and slip stops on the slickline-installed plugs, the creation of an entire recommended practice stating that service rigs must have rear egress (which would likely have prevented both fatalities), the creation of new egress to eliminate the need to untie oneself on the tubing board, the development of electronic controls so sensitive they can sense a ramshaft creeping 0.001“, and the creation of a whole new breed of snubbing units.
So how is this viable? Pulling singles on a snubbing unit and laying pipe down is a time-consuming process that introduces hazards which standing pipe does not. The laydown procedure can take minutes as you rely on the service rig winches and the rig crew to rack pipe on the ground. This led the way for the oilfield services world to introduce super capacity coiled tubing units to perform similar jobs. These coiled tubing units are capable of simple to complex jobs at almost any depth but they are limited because of their costs and weight of the units when in transport. A simple coil unit may go out for $20,000 or more per day and weigh upwards of 125,000 kilograms. The coil is a wearing component and must be replaced constantly in order to maintain integrity. But even with all these cons, the coil units prevailed because of the timing of the laying down of single joints.
So do we want to stand pipe again? Yes. Do we want to compete again? Yes. Will we place our employees at risk? No. We have not yet proven that these changes are sufficient to position a person back in the tubing board of a service rig. We are getting closer to determining an answer but until then, the industry is ripe for innovation.
I had the pleasure of witnessing one such innovation. It took a simple concept and process — and with some finesse — allowed racking of double stands in a service rig from the snubbing basket. It used rig-assist snubbing and with combined services having all of the safety equipment (installed as described above), it still allowed the timing to be sped up without the laydown of pipe. The standalone snubbing units that have been developed take considerably more time than this process and the coil units are considerably more expensive.
This technology, if embraced and deployed, may pull a few more snubbing units off the fence and put service rigs to work in place of coil. Why would it matter right now? In the cost competitive environment in which we live the operators need to improve their processes. In some applications this may not be the answer but in areas that need deep work completed and high pull and push capacities, this combination is now cost effective. Trucking in loads of jointed pipe that can be high grade, cheaply inspected, easily reused, and discarded 30 feet at a time instead of 6,000 metres at a time can be advantageous. Costs per day are lower as well as the impact on the highways can be lower simply because you don’t have one massive load working but rather several smaller loads.
What does the future hold for rig assist snubbing? I believe that this service will be in higher demand as operators review their well programs and realize that the combination of the two services can yield a highly efficient completion of any well task. Will we see further innovations? With this being the first version, time is bound to enhance what currently exists and make the process even safer. ?
Special thanks to the fellows at Goliath Snubbing and Roll’n Oilfield Industries for putting on the demonstration. More information can be found on goliathsnubbing.com