In the previous article dedicated to the CAMLogic column on ATEX revamping we talked about the assessment of the risk of explosion for new installations, but how to behave with machinery and equipment on the market before 2003, year of the first ATEX Directive 1994/9/EC? Fabrizio Bellini, revamping consultant, illustrates the fundamental steps to update industrial plants from before 2003.
Revamping: when to upgrade the industrial plant
Examination of the arrangement of the machinery
As in the case of a modern plant, the first step is the classification of the risk zones in terms of explosion hazard. The map thus defined is then overlaid on the plant layout to associate one or more zones with each machinery, also taking into account those induced by its operation or the process.
The overlap requires an inspection by expert personnel to evaluate the coherence between zones classification and machinery operation, and to associate each of them with a level of protection from the risk of explosion.
Evaluation of the feasibility of revamping
Based on the results thus obtained, the expert examines a possible transformation of the machine in question to respond to the safety requirements. In this case we’re talking of a revamping of the machinery, aimed at adapting to the safety requirements and general modernization. Updating the industrial plant with revamping includes different types of intervention, from extraordinary maintenance, to the functional implementation and control (retrofit) of the machinery.
Start of the revamping process
Once the feasibility study has been approved, the next phase focuses on the revamping project, also considering costs and downtime of the machinery. The process involves at least the following activities:
- drafting of technical specifications with graphic and photographic support;
- selection and purchase of the materials and components;
- mechanical and electrical replacement interventions;
At the same time, the technical file of the machine resulting from the revamping is prepared. The appointed expert also carries out the regulatory obligations and connects with a Notified Body, in the event that a certification is necessary.
At the end of the revamping the machine must be safe according to the regulations in force, likely also renovated thanks to the installation of new control and automation devices. And CAMLogic has the ATEX certification suitable also in cases of industrial revamping.
A practical example of revamping process
Suppose a machine has an axis that rotates on bearings, which by nature generate hot surfaces which could represent potential ignition sources.
The evaluation identifies the introduction of a temperature monitoring device to control the potential ignition source as a risk reduction measure. This sensor is linked to a control system that can block the machine if the safety limits are exceeded.
The same control system can be utilized to manage other useful parameters to optimize productivity, as is already the case for CAMLogic level indicators. However, it must be borne in mind that the adjustment to safety standards (revamping) is mandatory, while the improvement of performances (retrofit) is significant in relation to the increase of the plant productivity. If well conducted, both conditions and quality of work will improve.
When to renovate the industrial plant?
At this point a question arises: when is revamping advantageous compared to the purchase of new equipment? The reasons are not only of an economic nature, but include factors such as prolonged downtime for the plant and the adaptation of the interfaces that the replacement would require.
Usually revamping is the preferred way to renovate the plant, but not if:
- interventions on the machinery are too radical and expensive;
- the new equipment offers a productivity unattainable with the old one;
- a new machine guarantees better working conditions for the operators.
In any case it is advisable, before proceeding with the purchase of one or more new technologies, to consult an expert to understand if there are possibilities for revamping, optimizing the investment, the safety and the productivity of the entire plant.
Specifically in terms of increase of productivity of the plant, CAMLogic offers a status assessment service and expert intervention on the subject. Contact us if you want to increase production without changing the plant.