Condition Monitoring/Predictive Maintenance

TOTAL E&P UK, one of the largest exploration and production subsidiaries of the TOTAL Group has installed a 10,000 point + CitectSCADA system to provide monitoring - with full dual redundancy - of the control and safety systems for the giant St Fergus gas terminal in Scotland. The Terminal plays a key role in supplying Britain

There are many sources of machinery health and production availability information available to an organization's maintenance and operations staff. Two of the most commonly used sources of information are scheduled inspection of machinery and condition monitoring.

In most cases, scheduled inspection of machinery has been managed through a plant

By using the latest condition monitoring systems and services, manufacturing companies can reduce unforeseen breakdowns. Schaeffler UK's managing director, Kate Hartigan, explains

When owning and managing high value items like cars or homes, most people are comfortable paying insurance premiums. So, surely manufacturing companies need to ensure their high value capital goods are adequately insured against unforeseen breakdowns? After all, lost production could equate to tens of thousands, even hundreds of thousands, of pounds per day. Although the cost of machine components like bearings and motors is small compared with the total machine price, the cost of production downtime and consequential losses resulting from a component failure, are often significant.

Take a steel or aluminium manufacturing plant. The typical cost of production downtime is

For many organisations today, the most important issue is how to reduce costs to compete profitably in global markets.  The two key approaches to manufacturing cost reduction are Lean and TPM (Total Productive Maintenance).Lean reduces costs by eliminating waste in the end to end process, following Henry Ford's original dictum "the longer anything is in my factory, the more it costs me".

Total Productive Maintenance reduces costs by eliminating losses in equipment based processes - once you have a lean flow, the key is to run equipment as efficiently as possible. Both Lean and TPM are based on a foundation of 5S and Continuous improvement (Kaizen) and our success is based on helping companies develop this foundation as well as applying more advanced Lean and TPM approaches.

Plants can improve their efficiency and reduce costs by performing calibration history trend analysis. By doing it, a plant is able to define which instruments can be calibrated less frequently and which should be calibrated more frequently. Calibration history trend analysis is only possible with calibration software that provides this functionality.

Manufacturing plants need to be absolutely confident that their instrumentation products

If one could get the right mix of preventive maintenance (PM) and corrective maintenance (CM), things might not be so bad. If CM could be reduced to zero, that would be grand, but that is not going to happen. Amid the propositions of RCM, TPM, RCA, the Pareto rule, best laid plans, etc., one still must contend with randomness. When our programs result in high levels of performance, the limiting factor is often randomness. Using the concept of randomness in analyzing equipment failure events is helpful in establishing the realistic limiting factors in PM and CM program development and management.

Before getting enthused about understanding the technical milieu of equipment failure modes and causes, failure intervals and maintenance task development in recovering a dysfunctional maintenance program, first look for an opportunity of a large reward for a small resource expenditure.

One large reward, for example, could be a 50% reduction in corrective maintenance resulting from a program developed and implemented in-house (small resource expenditure). That 50% number is not unrealistic.

Predictive maintenance (PdM) techniques are commonly used on motors and drives. But how often is the power to the equipment inspected? Adding basic power quality measurements to equipment maintenance procedures can head off unexpected failures in both the equipment and the power system.

Cost savings
Insurance claims data in the NFPA 70B maintenance standard show that roughly half of the cost associated with electrical failures could be prevented by regular maintenance. A study published in IEEE 493-1997 says that a poorly maintained system can attribute 49 percent of its failures to lack of maintenance.

To determine the cost of a failure, it helps to consider three key categories:

The first step toward realizing this goal is to figure out where you are presently. Determining the present baselines and gaps that exist in your processes and organization is best accomplished by performing a reliability assessment. This exercise will point out the areas within your business that need to be addressed from a reliability perspective. All facets of your organization must be analyzed. We have identified 21 key elements that, when integrated, provide the basis for reliability excellence (Fig. 1). Assessing the current state of each of these elements will identify the gaps that exist and provide the basis for a master plan of improvement.

Master plan

A master plan is the tool that tracks what must be done, who will do it, and in what time frame the task(s) will be completed.

The master plan should initially outline the process-launching activities. These activities include reviewing the master plan and initiating the improvement process, developing the return on investment, establishing a reliability excellence leadership team, and identifing focus teams and support resources.

The definition and use of Overall Equipment Effectiveness over the years has been widely debated.

Many practitioners have found that OEE has several uses and definitions which have led to
considerable confusion when comparing machine-to-machine, plant-to-plant, or company-tocompany.
Unfortunately, OEE was not designed to make comparisons from machine-to-machine,
plant-to-plant, or company-to-company, but it has evolved to these common levels of misuse. OEE is not a statistically valid metric, but it has been used as such for years.

The purpose of this article is to discuss the original intent of Overall Equipment Effectiveness as a metric and a measure. I initially learned OEE from Seiichi Nakajima, the