The increasing crude oil and natural gas prices as well as the ever greater demand for fossil fuels means that new gas and oil fields are still being developed in the North Sea. The latest explorations lie far outside the areas that exist today and the oil and gas must be transported in pipelines over great distances in order to connect up with the network. Thousands of kilometers of pipeline being laid in the North Sea just to provide a power supply.
The sections of these pipes are 10 m long and 1.12 m in diameter. Their massive steel core is protected by a concrete layer with integrated steel reinforcement as well as a flexible bitumen layer. Once they have an outer coating, but before they can be welded together into a seamless pipeline, each section must again undergo a thorough internal cleaning. This takes place at large service points on land (“on shore”) and, due to the changing weather conditions, is done under extremely difficult circumstances. Pipes are then welded together on the open sea (“off shore”).
For a number of reasons, pipeline specialists prefer to use high-pressure cleaners to clean pipe interiors.
First and foremost, their extensive mobility is an important factor. Of course, it cannot be easy to transport thousands of pipeline sections. Therefore, they must be cleaned in situ. Moreover, high-pressure cleaners when used with the appropriate accessories are capable of adapting ideally to pipe cross-sections. Last but not least, the unlimited availability of water as well as the problem-free disposal of it after cleaning plays a role.
Yet again, the best choice for such a demanding project proved to be the Dynajet high-pressure cleaner from Putzmeister Mörtelmaschinen GmbH. The specialist firms responsible for preparing, handling and laying the pipeline used 4 Dynajet 500 th hot-water diesel units, which were supplied by our Norwegian retail partner “Hoytrykksenteret – Norge AS”.
The flexible and high-performance units were able to clean with ease and efficiency, even in the almost difficult to access areas of the service point. With a pressure of up to 500 bar and a maximum delivery rate of 30 liters per minute, the individual pipes were cleaned, degreased and prepared for further processing very quickly with a technically advanced nozzle system.
The nozzle system consisted of a rotating nozzle device that was mounted on an “interior cleaning carriage”. Using 3 runners, this carriage was able to be adapted precisely to the pipe diameter and positioned exactly in the middle of the pipe. This was important for maintaining an identical cleaning distance from the nozzle to the inner wall at all times and therefore to ensure an even clean. The nozzle recoil set the magnetically braked system in rotation, which meant that an external energy source was not required. The forward pushing motion into the pipes was manually applied by the machine operator.
The Dynajet high-pressure cleaner, model 500 th, is a hot water unit. At a temperature of approx. 80-90 °C, the cleaning speed could be further increased considerably. Universally adjustable parameters such as pressure, delivery rate and temperature allowed the machines to always be used at the ideal operating point. This led ultimately to a significant reduction in fuel consumption and operating costs.
The high reliability and the robust design of the device made it possible to work non-stop in 3 shifts, 24 hours a day, 7 days a week. This was absolutely necessary, as there were 96,000 pipes to be cleaned. On average, the 4 Dynajet high-pressure cleaners have tallied up nearly 19,000 operating hours in 2 years. This is an impressive example of high quality and power.
Mr Svein Inge Hansen, the manager at “Hoytrykksenteret – Norge AS” put it this way: “The power of the Dynajet high-pressure cleaner is unbelievable. No other machine could have achieved such outstanding performance in such a short time.”
High-performance, around the clock, even under the most difficult of conditions. Dynajet high-pressure cleaners have again demonstrated why they deserve their position at the top.
