The Corrosion Risk Assessment provides a relative risk ranking of the considered items with respect to the probability of a failure which implies the leakage of the conveyed fluid and the entity of the consequences.
Integrity Operating Windows (IOWs) are established following industry-recommended international standard API RP 584. They are developed to:
CESCOR can join the team as a corrosion and integrity specialist, able to propose tailored and pragmatic solutions suiting the client's requests.
CESCOR elaborates inspection plans and programs based on the logic of RBI (Risk Based Inspections). The structures to which the RBI methodology has been broadly applied, with punctual adaptations, are the plants for the treatment of oil and gas of the oil upstream, the plants of oil downstream and the plants of re-gasification.
Activity consists in a detailed risk analysis of all the components with the aim of categorising every component on the basis of the possible mechanisms of degradation and of real corrosion risk.
Starting from the components with the highest risk, some plans of inspection are elaborated in order to define the techniques of inspection for the survey of expected degradation mechanisms, and define, with the support of inspective sketches, the appropriate areas of investigation, their extension, and the necessary detail of investigation.
The elaboration of an inspective program containing inspective frequencies and their management is an integral part of the activities.
The RBI method can be applied both to new plants, planning it since the start of the development phase of the project, and on existing plants.
The first inspective survey is usually carried out in the first year of the operating life of the plants, the collected data constitute the base-line of the plant and have the purpose to confirm that the items lack of constructive defects.
For the working plants, the application of the RBI method consists in the periodic execution and planned frequencies of inspective surveys, the results of which properly filed and analyzed, constitute the starting point for the planning of following inspections.
The term fitness for service assessment indicates a procedure commonly applied in the oil and petrochemical sector to verify the eligibility of a component in pressure to operate in presence of material defects.
The pressure pipelines are subject to periodical inspections intended to individuate defects and determine their form and dimensions.
Starting from the inspective of the pipeline (ILI - In-Line Inspections), CESCOR applies the methodologies described in ASME B31G and DNV-RP-F101 codes for the analysis of criticality of the defects in comparison to the expected effort conditions. Additionally, CESCOR applies its own competence in the field of the corrosion to foresee a model of growth of the defect which keeps in consideration the real conditions of exercise of pipeline and transported fluids (for internal defects) and the external conditions of protection (for external defects).
Applying once again the mechanical codes it is possible to determine what defects will be critical ones in the future and when, allowing the operator to perform mitigating interventions avoiding the perforation of the pipeline.