La grenade est un fruit méconnu et encore peu commun sur nos tables... pourtant elle est pleine de vertus ! Bonne pour le coeur, contre les maux d'estomac, contre le vieillissement, contre le cancer... et plus encore .
Read more aliments-et-vertus-sante-les-bienfaits-de-la-grenadeCe qui rend la grenade encore plus exceptionnelle, c’est qu’elle combine les effets des tanins et des flavonoïdes lui conférant donc une double action anticancer
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Maintenance 4.0 how to said ? follow sebatec
1.3. Optimization efforts of maintenance
Maintenance has a role in all aspects of the plant’s organization. When reviewing the
organization it is important not only to examine the processes, but also the management
approach, work culture, skill set, motivation of the work force, and the effective use of the
technologies. Any of these could be blocking forces that can prevent a successful transition. A
carefully scripted plan for accomplishing a significant change in the organization is of the
utmost importance; otherwise significant time will be required to gain acceptance afterwards
and re-establish the lost confidence. The primary focus should be on optimization of plant
maintenance and a programme to create a work environment that optimizes the use of
resources, maintenance processes, employee skills and technology for the purpose of meeting
the maintenance objectives. Additional discussion of the optimization process is provided in
Section 3.
1.4. Structure
Section 1 introduces the background and related IAEA publications and Section 2 discusses
the benefits of condition based maintenance. Section 3 lays out various maintenance strategies
for optimization including conditional based maintenance. Then, Section 4 presents an
implementation example for a condition based maintenance process. Section 5 elaborates
many important condition monitoring techniques, such as vibration, thermography, tribology,
acoustics and motor currents. Section 6 lists necessary elements and key performance
indicators which a condition based maintenance reports shall describe. Section 7 discusses
how a condition base maintenance programme shall be evaluated in terms of technology,
organization and management, costs and benefits. Section 8 concludes the publication with a
number of points of lessons learnt provided by the publication contributors during the
consultancy meetings. In the appendices are selected technical papers on maintenance
optimization presented during the technical meeting.
2. TARGETS AND BENEFITS OF CONDITION BASED MAINTENANCE
Condition based maintenance is not a substitute for the more traditional maintenance
management methods. It is, however, a valuable addition to a comprehensive, total plant
maintenance programme. Where traditional maintenance management programme rely on
routine servicing of all machinery and fast response to unexpected failures, a condition based
maintenance programme schedules specific maintenance tasks as they are actually required by
plant equipment. It cannot totally eliminate the continued need for either or both of the
traditional programmes, i.e. run-to-failure and preventive, predictive maintenance can reduce
the number of unexpected failures and provide a more reliable scheduling tool for routine
preventive maintenance tasks.
2.1. Benefits of condition based maintenance
Maintenance costs are a major part of the operating costs of all manufacturing or production
plants. Depending on the specific industry, maintenance costs can represent between 10 and
40 per cent of the costs of goods produced. For example in food related industries, the average
maintenance cost represents about 15 per cent of the cost of goods produced; while in iron
and steel, pulp and paper and other heavy industries maintenance represents up to 40 per cent
of the total production costs. Discounting the cost of fuel for nuclear units, most power
production facilities in the United States of America also fall into the upper range of costs.
Machines are mounted so that the rotating shaft is horizontal or vertical with respect to the
earth’s surface. Gravity has more effect on vibration within horizontally mounted machines
than it does on vertically mounted machines. Gravity forces on horizontal machines are
perpendicular to the rotating axis and combine with rotating forces. A vertically mounted
rotating shaft has the force of gravity acting in the same direction as the rotating axis. The
rotating forces do not combine with gravity forces in a vertical machine.
Certain faults or problem conditions are more easily detected because of the type of machine
or components the faults occur in. For example, rolling element bearings (ball or roller
bearings) give more distinctive, earlier signs of wear than sleeve bearings do. Sleeve bearing
lubricant films (oil or water) prevent parts from impacting, except in extreme situations.
Rolling elements also have lubricant films (oil or grease). These films, however, may soften
but do not eliminate the impact between components.
5.1.1. Vibration analysis correlation
Integrating oil and vibration analysis can yield early detection and trending of numerous
equipment problems. Detecting the faults is the first step in the diagnostic process. Table 1
shows a comparison of the vibration and oil analysis detection capabilities for several
machine conditions.
Thermography can also be used to verify vibration analysis on rotating equipment.
Thermography can detect any overheating of bearings due to insufficient lubrication,
misalignment, and other causes.
Maintenance has a role in all aspects of the plant’s organization. When reviewing the
organization it is important not only to examine the processes, but also the management
approach, work culture, skill set, motivation of the work force, and the effective use of the
technologies. Any of these could be blocking forces that can prevent a successful transition. A
carefully scripted plan for accomplishing a significant change in the organization is of the
utmost importance; otherwise significant time will be required to gain acceptance afterwards
and re-establish the lost confidence. The primary focus should be on optimization of plant
maintenance and a programme to create a work environment that optimizes the use of
resources, maintenance processes, employee skills and technology for the purpose of meeting
the maintenance objectives. Additional discussion of the optimization process is provided in
Section 3.
Section 1 introduces the background and related IAEA publications and Section 2 discusses
the benefits of condition based maintenance. Section 3 lays out various maintenance strategies
for optimization including conditional based maintenance. Then, Section 4 presents an
implementation example for a condition based maintenance process. Section 5 elaborates
many important condition monitoring techniques, such as vibration, thermography, tribology,
acoustics and motor currents. Section 6 lists necessary elements and key performance
indicators which a condition based maintenance reports shall describe. Section 7 discusses
how a condition base maintenance programme shall be evaluated in terms of technology,
organization and management, costs and benefits. Section 8 concludes the publication with a
number of points of lessons learnt provided by the publication contributors during the
consultancy meetings. In the appendices are selected technical papers on maintenance
optimization presented during the technical meeting.
Condition based maintenance is not a substitute for the more traditional maintenance
management methods. It is, however, a valuable addition to a comprehensive, total plant
maintenance programme. Where traditional maintenance management programme rely on
routine servicing of all machinery and fast response to unexpected failures, a condition based
maintenance programme schedules specific maintenance tasks as they are actually required by
plant equipment. It cannot totally eliminate the continued need for either or both of the
traditional programmes, i.e. run-to-failure and preventive, predictive maintenance can reduce
the number of unexpected failures and provide a more reliable scheduling tool for routine
preventive maintenance tasks.
2.1. Benefits of condition based maintenance
Maintenance costs are a major part of the operating costs of all manufacturing or production
plants. Depending on the specific industry, maintenance costs can represent between 10 and
40 per cent of the costs of goods produced. For example in food related industries, the average
maintenance cost represents about 15 per cent of the cost of goods produced; while in iron
and steel, pulp and paper and other heavy industries maintenance represents up to 40 per cent
of the total production costs. Discounting the cost of fuel for nuclear units, most power
production facilities in the United States of America also fall into the upper range of costs.
Machines are mounted so that the rotating shaft is horizontal or vertical with respect to the
earth’s surface. Gravity has more effect on vibration within horizontally mounted machines
than it does on vertically mounted machines. Gravity forces on horizontal machines are
perpendicular to the rotating axis and combine with rotating forces. A vertically mounted
rotating shaft has the force of gravity acting in the same direction as the rotating axis. The
rotating forces do not combine with gravity forces in a vertical machine.
Certain faults or problem conditions are more easily detected because of the type of machine
or components the faults occur in. For example, rolling element bearings (ball or roller
bearings) give more distinctive, earlier signs of wear than sleeve bearings do. Sleeve bearing
lubricant films (oil or water) prevent parts from impacting, except in extreme situations.
Rolling elements also have lubricant films (oil or grease). These films, however, may soften
but do not eliminate the impact between components.
5.1.1. Vibration analysis correlation
Integrating oil and vibration analysis can yield early detection and trending of numerous
equipment problems. Detecting the faults is the first step in the diagnostic process. Table 1
shows a comparison of the vibration and oil analysis detection capabilities for several
machine conditions.
Thermography can also be used to verify vibration analysis on rotating equipment.
Thermography can detect any overheating of bearings due to insufficient lubrication,
misalignment, and other causes.
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