Gas transportation pipelines convey large volumes of product in a cost-efficient manner, with gas typically moving at rates above 8 m/s. Vital to the cost-effective transportation of any medium is the maintenance of the pipeline’s internal diameter because the smallest amount of deposit can hinder performance. This means optimal cleaning techniques and performance are crucial to maintain or even increase the efficiency of transportation.

Recently, colleagues from our Asia Pacific region and our location in Lingen (Ems), Germany were entrusted with a solution for cleaning a pipeline in Australia. This involved special challenges which we mastered with the help of our EcoSpeed technology.

The Challenge

Ideal cleaning performance is achieved when cleaning tools travel at lower speed, i.e. below 5 m/s. Running cleaning tools at higher velocity can lead to inferior performance of the tools due to high abrasion on discs and cups, which in turn leads to substandard cleaning. Consequently, for cleaning programs to be most effective, high-velocity gas pipelines often require significant cutbacks to achieve safe and optimal parameters for cleaning operations. Of course, lowering the production speed of any asset also has a dramatic effect on operations and financial performance.

In this case, a natural gas producer in Australia requested a solution from ROSEN for cleaning a gas pipeline with high flow velocities. The 24" natural gas pipeline is 30 kilometers long and has gas velocities up to 18 m/s. The operator's expectations were clear: an effective cleaning solution with minimal reduction in gas flow. Good cleaning results are usually expected at velocities between 2 m/s and 7 m/s. To achieve this, the operator needed to reduce the gas pipeline flow to 7 m/s in the past, as the tool is pushed through the pipeline with the medium and thus normally moves at the same speed.

The Solution

With our so-called EcoSpeed service, we have the perfect solution for such requirements in our portfolio. The EcoSpeed technology is based on a mechanical bypass valve. This way, the speed of the tool can be reduced by up to 7 m/s in a controlled manner despite a high gas flow rate and a good cleaning result can be achieved. With the help of the valve, part of the medium flows through the tool. Following, the differential pressure and thus the speed can be reduced.

EcoSpeed Service Tool.

The Benefit

After we had adapted the EcoSpeed tool to the pipeline, we were able to calculate and simulate the bypass as well as the speed reduction. The result indicated that we could reduce the speed of the EcoSpeed tool by up to 6 m/s in this pipeline. With this result, the gas flow only needs to be reduced to 13 m/s instead of 7 m/s to allow efficient cleaning. The operator was very happy with this result and gave us a 'go' for cleaning.

The Result

The run took place successfully and our previous calculations and simulations were confirmed. As expected, the EcoSpeed tool maintained an average speed of 7 m/s, while the speed of the gas was 13 m/s. The operator was very satisfied with the result – another success story of our EcoSpeed fleet!