Effective Maintenance Management. V. Narayan

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       1.5.2 Efficiency and non-renewable resources

      An increase in efficiency, whether it is at the production or at the consumption end, reduces the total inputs and hence the demand for resources. We can ease the pressure on non-renewable resources greatly by doing things efficiently. In this context,the efficiency of both producer and consumer are important.

      The first step in improving efficiency is to measure current performance. Qualitative or subjective measurements are perfectly acceptable and appropriate in cases where quantitative methods are impractical.

1.6 MAINTENANCE—THE QUESTIONS TO ADDRESS

      We have looked at the holistic aspects of maintenance so far. What do we actually achieve when we carry out maintenance? Capital investments create production capacity. This capacity will decrease with use and time, unless we take the right actions—which we call maintenance.Equipment degrades with use, due to a variety of reasons. It can get internally fouled by particulates or residues from the process or materials of construction.It may deteriorate due to wear, corrosion, erosion, fatigue,or creep. These mechanisms lead to component and equipment failure, resulting in equipment unavailability, and maintenance costs. Unavailability can affect safety or production,so we want to keep that as low as economically possible. Planned downtime has lower consequences than unplanned downtime, so we try to minimize the latter.

      What do we mean by the term maintenance? The British Standard BS 4778-3.1:1991 defines it as “...actions intended to retain an item in, or restore it to, a state in which it can perform its intended functions.” In simple terms, we need equipment to do something for us, i.e., to have a function. To retain that function over its life, we have to do maintenance.

      Loss of process safety can lead to serious accidents, such as that in the Texas City Refinery in March 2005. An Independent Safety Panel Review headed by (former Secretary of State) James Baker investigated and concluded that “When people lose an appreciation of how their safety systems were intended to work, safety systems and controls can deteriorate, lessons can be forgotten, and hazards and deviations from safe operating procedures can be accepted. Workers and supervisors can increasingly rely on how things were done before, rather than rely on sound engineering principles and other controls. People can forget to be afraid.”^1,2.

      Maintenance is central to process plant performance, as it affects both profitability and safety. How well we do it depends on our ability to answer the questions, what work to do, when to do it, and the process steps to use. Doing so efficiently means we will do the minimum volume of work at the right time in the right way.

      When an item of equipment fails prematurely, we incur additional maintenance costs and a loss of production and/or safety. As a result we cannot utilize the full capability of the equipment. Timely and effective maintenance helps avoid this situation. Good maintenance results in increased production and reduced costs. Correct maintenance increases the life of the plant by preventing premature failures. Such failures lead to inefficiency of utilization and waste of resources. The need to minimize these losses is why we need to maintain equipment. We will examine the purpose and mechanics of maintenance further in Chapter 9. There, we will see that the role of maintenance is to ensure the viability and profitability of the plant. In Chapter 10, we offer guidance on the strategies available to you to find the most applicable and effective tasks and to select from these the ones with the lowest cost. At the end of Chapter 10, you should have a clear idea of what tasks are required and when they should be done in order to manage the risks to viability and profitability of the plant. In Chapter 12, we will discuss how a plant performing poorly can take systematic steps to become a top performer.

1.7 CHAPTER SUMMARY

      We began this chapter by defining the production and distribution processes and then looked at some of the factors that influence efficiency. We use costs to measure performance; low costs imply high efficiency. When measuring costs, we make simplifications,as a result of which we may introduce some distortions.

      We discussed how we compute the value of work, using production costs or competitive market prices. We noted that there are some sources of error in arriving at the value of work.

      Thereafter, we saw how manufacturing and service industries add value. Manufacturing productivity has grown dramatically, due to cheap and plentiful electro-mechanical power and, more recently,computing power. A beneficial cycle of increased productivity—raising the buying power of consumers—results in increased demand. This has lowered prices further, encouraging rapid growth of manufacturing and services industries.

      Manufacturing and service industries similar processes. The systems approach helps us to understand these, and how to control them.We illustrated this similarity with a number of examples.

      Thereafter, we examined the impact of efficiency on the use of resources. We noted that cost is a measure of efficiency, but recognize that all costs are not visible; hence distortions can occur. With this understanding, we saw how to use costs to monitor efficiency. A brief discussion of the role played by maintenance in managing safety, availability and costs sets the stage for a more detailed examination later. We will address the questions why, what and when in regard to maintenance as we go through the book.

       REFERENCES

      1.Original Baker report is at http://www.bp.com/liveassets/bp_internet/globalbp/globalbp_uk_english/SP/STAGING/local_assets/assets/pdfs/Baker_panel_report.pdf

      2.UK HSE report. http://www.hse.gov.uk/leadership/bakerreport.pdf

Chapter 2

       Process Functions

      The term process describes the flow of materials and information. In order to achieve our business objectives, we use energy and knowledge to carry out the process.

      The purpose of running a business is to produce or distribute goods (or services) efficiently. A business uses its mission statement to explain its objectives to its customers and staff. This is a top-down approach and enables us to see how to fulfill the mission, and what may cause mission-failure. We call this a functional approach, because it explains the purpose, or function, of the business. We can judge the success or failure of the business by seeing if it has fulfilled its function, as described in the mission statement. A high-level function can be broken down into sub-functions. These, in turn, can be dissected further, all the while retaining their relationship to the high-level function.

      After reading this chapter, readers who are unfamiliar with this approach should have acquired an understanding of the method—this is the mission or function of this chapter. The main elements of the method are as follows:

      •The functional approach, methodology, and communication;

      •Identification СКАЧАТЬ