CHAPTER 1

INTRODUCTION

Since the Industrial Revolution, maintenance of engineering equipment

in the field has been a challenge. Although impressive progress has been made in

maintaining equipment in the field in an effective manner, maintenance of equipment

is still a challenge due to factors such as size, cost, complexity, and competition.

Needless to say, today’s maintenance practices are market driven, in particular for

the manufacturing and process industry, service suppliers, and so on. An event may

present an immediate environmental, performance, or safety implication. Thus, there

is a definite need for effective asset management and maintenance practices that will

positively influence critical success factors such as safety, product quality, speed of

innovation, price, profitability, and reliable delivery.

The activity of equipment/item maintenance that develops concepts,

criteria, and technical requirements in conception and acquisition phases to be used

and maintained in a current status during the operating phase to assure effective

maintenance support of equipment. Due to various factors, it was established in the

previous century that “maintenance” must be an integral part of the production

strategy for the overall success of an organization.

Maintenance is defined as the routine and recurring process of keeping a

particular machine or asset in its normal operating condition so that it can deliver the

expected performance or service without any loss or damage. One among the

maintenance process is Predictive Maintenance. Predictive maintenance is the

management technique that uses regular evaluation of the actual operating conditions

of plant equipment, production systems and plant management functions to optimize

total plant operation. One of the methods in Predictive maintenance is Condition

monitoring.

Condition monitoring is the process of monitoring a parameter of

condition in machinery (vibration, temperature etc.), in order to identify a significant

change which is indicative of a developing fault. It is a major component of

predictive maintenance. The use of conditional monitoring allows maintenance to be

scheduled, or other actions to be taken to prevent failure and avoid its consequences.

Condition monitoring has a unique benefit in that conditions that would shorten

normal lifespan can be addressed before they develop into a major failure. Condition

monitoring techniques are normally used on rotating equipment and other machinery.

There are many techniques in condition monitoring. We are employing Vibration

analysis as a method in Condition Monitoring.

The use of machinery vibration and technology advances that have been

developed over the year makes it possible not only to detect when a machine is

developing a problem, but to identify its specific nature of problem for the scheduled

correction. When a machine fails or breakdown, the consequences can range from

annoyance to financial distortion or personal injury and possibly loss of life. Thus

vibration analysis is of great importance and it not only minimizes the need of

extensive experience, but also makes it possible to detect the developing problems

which are outside the range of human senses to touch and hearing. Here the

introduction of vibration analysis and outline a simple, logical and systematic

approach that has been proved successful in pinpointing the vast majority of most

common day to day machine problems is done.

The vibration analysis we are going to do is a part of conditional

monitoring techniques and it’s mainly used for the improved performance of

equipment. Using this we can predict the condition of the internal parts of the

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equipment. Thus this is a type of predictive maintenance techniques. We are mainly

dealing with the vibration analysis on rotary equipment. It includes typical causes of

vibration like misalignment of shafts, looseness, bearing faults, unbalance, oil

fracture etc. Machinery distress very often manifests itself in vibration or a change in

vibration pattern. Vibration analysis is therefore, a powerful diagnosis tool, and

trouble shooting of major process machinery would be unthinkable without modern

vibration analysis.

It is natural for machines to vibrate. Even machines in the best of

operation condition will have some vibration because of minor defects as a result of

manufacturing tolerances. Therefore each machine will have a level of vibration

which may be regarded as normal or inherent. When machinery vibration increases

or becomes excessive, some mechanical trouble is usually the reason. Machinery

vibration levels just do not increases or become excessive for no reason at all.

Something causes it unbalance, looseness etc.

Each mechanical defect generates vibration in its own unique way. This

makes it possible to positively identify a mechanical problem by simply measuring

and studying its vibration characteristics. The success of a process industry often

depends on the continued, safe and productive operation of rotating machinery. An

effective maintenance program is vital to this kind of success. The quality of the

company’s maintenance program determines how long the machines will run, how

safe they are for the people working around them.

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