Between 2016 and 2019, approximately 330 million soles were invested in 872 maintenance operations for the ONP pipeline and pumping stations. In this period, the amount of maintenance has increased year by year. In 2016, there were 127; in 2017, 242; in 2018, 247; and in 2019, 256. Only in 2019, 130 million soles were budgeted for maintenance operations.
The annual maintenance plan considers several items to be developed, among these there is the reinforcement of the pipe due to geometric anomalies and loss of thickness, the relaxation of the pipe, the replacement of pipe sectors, the inspection of the state of the pipe in river crossings, reinforcement of river banks and slope stabilization, and maintenance of the equipment of the Pumping Stations.
Comprehensive pipeline evaluations are carried out through internal inspection with state-of-the-art tools (ultra-high resolution). These tasks consider the measurement of the internal geometry of the pipe, the mapping and inertial positioning, the measurement of thicknesses in the entire route of the pipe, and the detection of both circumferential and longitudinal cracks. These works are carried out within the framework of maintenance plans, which meet technical standards and the criticality of the anomalies reported to Osinergmin.
These inspections allow the detection of small cracks and pinholes that previously went unnoticed.
Before sending the scraper along the ONP, gauge plates are passed to determine the condition of the pipe, in order to find any crushing, bumps or collapse that have deformed it. Once the good condition of the tube has been verified, the scraper tubes with instrumentation are launched to determine the presence of wear in the thickness of the pipe or the presence of cracks in it. This gauge advances from station to station. The inspection takes a year, to which must be added the time it takes to interpret the information. Results are obtained in forty-five days. From this, both repairs and reinforcements are planned. First, critical points that have lost more than 80% of their thickness are addressed, then those that can be addressed in a few months and finally those that must be solved in a year.
Repairs in the ONP are not exclusively in the pipeline, they are also done in turbines, electric pumps, tanks, etc. There are many repairs that are carried out in an ONP Pumping Station. Repairs to the pipe are specifically to reinforce the pipe. This is the result of the detections by the pipe scratcher, which runs through the tube and indicates a problem in a certain kilometer.
Reinforcing the pipe means placing a sleeve on a certain part that has wear in its thickness. A shirt is two half moons of pipe, with a different coverage. These two half moons hug the pipe and are fixed to it by linear or circumferential welding. It is like a staple, but it is two pieces welded together. It is practically like having two pipes, one on top of the other. This work can be done with the crude inside the pipe. Far from being a risk, the crude dissipates the heat produced by welding. A product is then injected to fill the gaps between one tube and another. This removes oxygen to prevent further corrosion of the pipe.
These reinforcements are carried out in less than 24 hours thanks to the good technical level of the personnel and their experience. What takes the longest is to dig up the pipe and remove the coating, which is very resistant.
The 256 maintenance operations that were planned for 2019 along 1106 kilometers mean that a possible problem has been prevented every 4.3 kilometers of the pipe, that is, it speaks well of the integrity, operability and continuity of the Pipeline. In addition, not all these maintenance operations are in the same tube, but in rivers, hillsides, river banks, since in many cases it is about reinforcement in the field.
It should be noted that the thickness of the pipe varies. The one that crosses the rivers is thicker, since it is assumed that never again will work be done under the riverbed. Likewise, the pipeline at the beginning (the one at Andoas Station in the ORN and Station 1 in Section 1), exposed to a lot of pressure, is more robust than the one at the end of the route. In all cases, it is the same material, that is, API5N and X52, which is the API standard type that governs the type of pipe. The shirts are also of the same material because there cannot be different materials.