Surface finishing facilities: Cutting down on downtime

Plant maintenance has often been a mainly reactive process, with parts run until they failed and then replaced. However, the drive to optimise productivity, reliability and to consistently deliver against schedule commitments means this approach has become outdated. The focus has switched to the proactive management of the maintenance and servicing of plant equipment. In essence the approach is one of preventative maintenance – taking deliberate, planned steps to minimise the risk of failure of mission-critical equipment before it can happen. Instead of the cost of individual parts being at the heart of decision, total cost of ownership (TCO) of plant is now the main driver.

A variety of techniques are typically implemented in a preventative maintenance programme, with activity centred on time-based, condition-based or usage-based monitoring. Regular tasks are undertaken such as checks on critical equipment, oil and filter changes and lubrication, with the condition of equipment recorded. Undertaking this regularly provides maintenance teams with information on the rate of deterioration of critical parts, and the likely date at which they will fail – allowing them to schedule shutdowns at convenient times for replacement of individual components, routine maintenance and servicing, or a complete overhaul. A strategy can also be put in place to look at alternatives for parts identified as ‘bad actors’ – those which do not reach their expected service life or require regular interventions.

Equipment used in a surface finishing facility generally falls under three main categories: automated lines, manual lines, and fume extraction systems. Automated and manual processing lines typically cover processes such as cleaning, chemical etching, electroless plating, electrolytic plating, hard or chromic anodising, tartaric sulphuric anodising (TSA) and conversion coating, such as alocrom or phosphating. Usually designed to fulfil application-specific requirements, fume extraction systems are employed to control pollution and emissions and fulfil biological monitoring.

Potential threats to operation

Each type of plant is subject to a variety of potential threats to operation: Overheating equipment is liable to unanticipated and catastrophic failure. This often emanates from the failure of heating and cooling elements. In the worst cases, this can cause a fire – an even greater risk in sites where flammable chemicals are used.

Chemical spills and leaks, either during handling, or as a result of inadequate or failing pipes, valves or pumps, can cause severe damage to nearby equipment if it is not sufficiently protected, to say nothing of the health & safety ramifications for operatives working in the area.

Fume extraction equipment, if not properly maintained, can subject employees to unsafe levels of noxious gases and other health hazards.

Virtually any component in moving equipment will eventually wear and, if not replaced, is liable to fail without warning, leading to potentially catastrophic failure of the machinery and unscheduled downtime.

To guard against these issues – or at least to be in a position to proactively manage the deterioration of parts – a regular, planned programme of maintenance and servicing is essential. Strict testing should be undertaken on all moving parts in mechanical operations, as well as tanks structures. In electrical, control and automation applications, gauges, sensors and control devices must be inspected regularly to ensure they are functioning optimally. Similar rigorous attention should be paid to the condition of current feeds and the physical integrity of cabling and trunking. 

These procedures, coupled with thorough analysis of the ongoing condition of components, will make a significant impact on reducing the risk of unscheduled downtime resulting from unplanned or catastrophic component failure and enable a proactive approach with regular scheduled plant stoppages for major tasks or system overhauls. Whatever the size and make-up of the surface engineering facility, the effects will be immediate and positive.

Different types of service and maintenance outsourcing support are available. NHE offers a holistic approach to complex process plant servicing and maintenance, offering a tiered structure suited to different operational requirements. By outsourcing the maintenance of process plant to a specialist provider, manufacturing facilities can take reassurance from the fact they are taking steps to improve critical asset reliability and performance and avoid costly unplanned downtime.