Plant owners are increasingly looking to outsource the major elements of equipment maintenance to improve reliability and limit downtime, reports rotating equipment maintenance and repair service provider Sulzer.

Plant maintenance for the mining industry is a highly skilled operation that requires considerable resources for unexpected repairs and long-term planning for preventive maintenance programmes. Large-scale equipment, such as gas turbines, generators, compressors and large pumps, requires specialist knowledge and expertise to maintain the most effective performance.

Time is money and plant owners globally aim to enhance productivity and reduce costs; central to this objective is avoiding unexpected breakdowns which can incur huge costs in terms of lost production. Implementing a robust preventive maintenance programme is the first of many actions that can be taken to reduce the incidence of failure.

Depending on the equipment, a number of techniques, such as vibration analysis, thermal imaging, flow measurement and power consumption, can be used to indicate the initial stages of a concern. Recording this data also builds up a useful asset history which can be used to predict failures and enable intervention that shortens repair times.

In many cases, this low- level monitoring will be carried out by on-site engineers, while the data analysis may be conducted by an original-equipment manufacturer (OEM) or a similar product specialist, such as Sulzer.

Once there is an indication that a repair is required, or a piece of equipment is scheduled for a predetermined overhaul, the aim is to implement a strategy that will reduce disruption and return the plant to normal operation as soon as possible.

Improving this process requires considerable planning, both in terms of labour and spare parts. Specialist maintenance contractors can provide expert advice and practical assistance in preparing for a major plant service. Experience in these projects is essential to ensure the overhaul takes place smoothly and on-site management can also be supplied in addition to technical support.

In some cases, such as with large gas turbines, the OEM may initially have a fixed contract to deliver a long-term service agreement. However, once this has expired, the plant owner is free to continue with a similar arrangement or to engage an independent provider. In many cases, the independent option is more attractive, especially in terms of the response time and parts repairs, which can be critical in returning the asset back to normal operation.

With such high-value assets, it is common for plant owners to maintain a stock of spare components, which are either stored on their premises or stored and managed by their independent maintenance partner.

For example, spare rotors for compressors are usually held so that when a planned maintenance shutdown is carried out, the service rotor can be swapped out for the spare, reducing downtime for the plant.

Once the compressor has been recommissioned, the inspection and the repair of the removed rotor can be carried out.

The plant operator then has to choose a service provider. The scale of the service will differ between them; some will provide a standard repair of damaged components, while others will offer the opportunity to enhance the rotor’s performance and efficiency through the improvement of the original design.

The level of technical expertise also influences the ability of a maintenance provider to support a client in the event of an unexpected failure or forced outage. These events are a worst case scenario for a plant manager and it is essential that repairs are completed as quickly as possible, says Sulzer.

To achieve this, maintenance providers need to be able to deliver labour and facilities at short notice.

Long-term maintenance contracts offer several advantages and can be tailored to suit each client. From basic planning, project management and parts supply and repair to complete technical support, including asset improvement and life extension, the level of support can be adapted to each set of circumstances.

Those plants taking advantage of these contracts can provide a fixed budget for many aspects of the maintenance contract and improve their maintenance strategy, adds Sulzer, noting that the level of engineering expertise and facilities of the service provider will have an impact on the length of maintenance periods and time lost for repairs.

Asset management plays a crucial role in determining the reliability and performance of any industrial process, highlights the company.

In many cases, engaging an experienced and well-resourced maintenance partner, such as Sulzer, can improve project management, make repairs more cost effective and improve productivity, while also providing a fixed cost basis, which will help with budgeting.