In Europe, more than 50 % of the budget devoted to infrastructure development is earmarked for the maintenance and modernization of existing facilities. This makes it all the more important to assess the residual lifespan of installations. This provides manufacturers in all sectors with information on the state of health of their equipment, and offers them recommendations for extending their useful life while guaranteeing operational safety. Interview with Bruno Depale, Cetim's expert in structural calculations.
Can a manufacturer use a piece of equipment safely and without question until the end of its contractual life?
Bruno Depale: Yes, an industrial company can do this in accordance with its contract, but it's important to note that the contractual service life is a theoretical figure provided by the manufacturer and is often linked to a number of cycles. The actual service life of a piece of equipment (component, machine, infrastructure, etc.) depends, in reality, on the way it is used and the frequency with which it is used. It is therefore also recommended that all manufacturers carry out a health check on equipment when it reaches 80 % of its contractual life. The same applies in the event of premature aging, a major incident, an increase in the number of failures, a substantial change in use, or a transformation in relation to its initial design. Since a piece of equipment is made up of several components with different lifetimes and heterogeneous levels of damage, it is always the most critical component that gives the shutdown point. Only a study of the residual state of health, going well beyond a simple annual inspection, enables operators to project the future use of their infrastructure or equipment in a secure manner.
How is residual life assessed?
B. D : As soon as a piece of equipment is used, its initial health capital is eroded. To assess its residual lifespan, the experts conduct an investigation through time. The challenge is to reconstitute an equipment's usage history in order to predict its future life. For example, determining the frequency and distribution of loads lifted by a lifting device, notable damage, maintenance operations, etc. If the risks become too great, machine shutdown may be recommended. In the vast majority of cases, however, the initial operating life can be extended by pragmatic combinations of repair solutions or reinforced surveillance. For example, the downgrading of a lifting device (reduction of its lifting load) can be combined with spot repairs (removal of corroded parts) and more frequent inspections limited to the most critical areas.
What technological developments can reinforce this expertise?
B. D : Part of our future lies in the development of innovative technologies that enable us to better anticipate maintenance operations and failure risks in real time. In addition, the integration of wireless sensors and the automatic transmission of their data into the network (SHM) are opening up new control applications that were previously impossible in structural health monitoring. On the other hand, IIoT, data processing and Big Data have made great strides in recent years and are becoming more accessible. All these innovations complement the survey and help decision-making. However, they do not replace the expert engineer who determines the best measures to take to ensure continued safe operation.