Preventative maintenance items

Preventive Maintenance Item Daily Weekly Monthly Quarterly... 

Customer supplied products that are issued for incorporation into supplies don t often require maintenance however, items for use in conjunction with the contract may be retained for such a duration that maintenance is necessary. If the products require any maintenance you should be provided with a maintenance specification and the appropriate equipment to do the job. Maintenance may include both preventive and corrective maintenance but you should clarify with your customer which it is. You may have the means for preventive maintenance, such as lubrication and calibration, but not for repairs. Always establish your obligations in the contract regarding customer supplied product, because you could take on commitments for which you are not contractually covered if something should go wrong. You need to establish who will supply the spares and re-certify the equipment following repair. 

Troubleshooting deals with identifying and solving problems. Problems can be immediate or long term and can be associated with off-spec products, poor efficiency, process improvements, capacity increases, or potential shutdown items. Problems can be related to management, operation, hardware and equipment, or process issues. Solutions can include improved operating procedures and training, preventative maintenance, or installation of new equipment or controls. 

Operation of a system on a continuing basis requires regular monitoring and maintenance. This phase represents the largest cost items of a long-term project however, routine adjustments of pumping units, coupled with preventative maintenance, will result in lower long-term costs. 

Annual preventive maintenance, in which most wearable items such as pistons, seals, lamps, and filters are replaced, is to be scheduled before calibration. 

The wastes generated during paint application are primarily due to 1) paint overspray, and 2) the failure of the application which requires the stripping, cleaning, and repainting of the item. Source reduction can be achieved by use of low overspray application equipment, proper operator training, preventive maintenance, and parts inspection. 

The maintenance plan will normally form part of the preventative maintenance system for the site and must be used to track all maintenance activities on the computer system and associated measurement and control instrumentation. For computer systems the supplier may be contracted for different levels of ongoing maintenance support, and it is acceptable to use the supplier procedures for maintenance of the specialist areas of the system. A supplier maintenance contract needs to define the scope of maintenance (e.g., the items to be maintained, type of activities, period of the contract, access requirements,... 

For each system, procedures for preventative maintenance (including periodic calibration or revalidation) should be established. The objective of preventative maintenance is to check, calibrate or replace critical system components to prevent future failure and/or breakdown of the system, as this could have a negative effect on the quality of the product (or data). The following items need to be covered in the preventative maintenance procedure(s) ... 

In conjunction with the tool kit, it is prudent to maintain a supply of consumable items that can be used in an emergency or as part of a preventative maintenance programme. A list of common consumable items that you might expect to keep in the laboratory is given in Table 10.2. 

Preventive maintenance is maintenance executed at predetermined intervals or according to prescribed criteria, aiming to reduce the probability of failure or the probability that an item will (Mily fulfill its functions to a limited extent (degradation of functioning). 

If item failure proposes no critical effect, reactive maintenance is more cost effective. Various forms of preventive maintenance are standardized according to the European Standard EN 13306 (Fig. 2). 

The objective of preventive maintenance is to extend the life of an item and prevent all failures before they occur by detecting critical wear that leads to failure or breakdown. This can be accomplished by estimating a lifetime schedule for each item. The way this estimation takes place determines the type of preventive maintenance. In predetermined maintenance the estimation is static and results in static maintenance intervals. In condition-based maintenance, maintenance intervals are determined according to either the detection of a degradation mechanism by monitoring or a forecast derived from the analysis and evaluation of a number of parameters (i.e., vibration, imbalance, machine noises, power demand) of the degradation mechanism (thus, condition-based maintenance is often referred as predictive maintenance). 

It is assumed in preventive maintenance that preventive repair or replacement of items would be appropriately timed if they were to occur just prior to their failure. In most preventive maintenance approaches, the estimation of the useful life of an item is replaced by the estimation of its reliability at any given point during its life, i.e., the ability of the item to perform its required function for a given time interval. In order to do so, statistical distributions are used to describe the stochastic failure behavior of the items. Among the most commonly used statistical distributions... 

Using such distributions of the remaining life of an item, the remaining life for an item for which a failure can be prevented by replacing or servicing the item is calculated and thus the preventive maintenance intervals for the item determined (Lanza et al. 2009 Gertsbakh 2006). 

Preventive maintenance activities include equipment checks, scheduled or craidition-based worn tool changes, cleaning, and partial or complete overhauls at specified periods, e.g., oil changes and lubrication. In addition, workers can record equipment deterioration so they know to replace or repair worn parts before they cause system failure. In the case of condition-based maintenance, sensors and software tools are used for the monitoring and analysis of the desired item parameters. 

Preventive maintenance is applied when the expected useful life of an item can be confidently estimated or when prediction models for the mechanism of wear of an item are available. The fact that preventive maintenance is a costintensive activity dictates that it is applied to items whose failure is critical to the system or could pose dangers to the operators. In order to identify the right type of maintenance. 

Structures, systems and components important to safety should be included in the preventive maintenance programme. The operating organization should review the programme as appropriate in order to ensure that items important to safety have been properly identified and classified, and that the applicable requirements of the... 

One of the most effective safety practices, as well as one highly conducive to productivity, is a definite scheduled program of preventive maintenance. Each item of equipment should be periodically removed from service, carefully inspected and calibrated, any faults or indications of deterioration repaired, and tagged with the date of review and the name of the maintenance person, if more than one technician could have been responsible. A permanent file or maintenance log on each major item of equipment is useful for identifying trends or weak components. 

At many facdities, the practice is to operate the incineration system continuously until it breaks down because of equipment failures. This type of operation accelerates both bad performance and equipment deterioration rates. Repairs done after such breakdowns are usually far more extensive and costly than those performed during routine, preventive maintenance procedures. Also, items which are typically capable of lasting many years can fail in a fraction of that time if interrelated components are permitted to fail completely. 

This same individual also noted that preventive maintenance resources had been significantly reallocated and optimized over the last 10-20 years. In particular, some types of equipment (such as engines) have become substantially more reliable over the years, so much less maintenance of those items is done today than prior to deregulation. In other cases, however, intervals between maintenance visits have been tightened, since older aircraft are now known to require more frequent inspections in certain areas. 

As part of a planned, preventative maintenance (PPM) schedule, pump oil should be drained and sterilised before discarding together with decontaminated filters, used gaskets, seals and components which have been changed during maintenance. After the PPM schedule, the freeze-drier should be validated to confirm the correct functioning of the drier and components including specialist items added to ensure safe operation. 

The reliability of a plant is a sum of reliabilities of all the equipment, instruments, and other hardware. The reliability of each item of equipment is estimated based on its past operational performance (failure rates, repair durations, etc.) and on current maintenance practices (preventive maintenance intervals and durations, test intervals, etc.). Once the economic impacts of various scenarios in which units or major equipment items fail has been established, the required safety features can be designed (e.g., profit-risk scenario and minimal cutoff could be established) (see Fig. 8.10). To the left of the dotted line in the figure, the litigation cost is higher than the cost of safety features the reverse trend exists on the right of the dotted line. 

A programme to prevent business interruption can include planned lubrication, planned preventive maintenance, condition monitoring, statutory inspections, machinery replacement programmes, availability of key spares, identification of key machines, processes, areas, personnel etc. within the organisation, continued supply of raw materials, minimisation of production bottlenecks, and highlighting dependencies on specific items of plant, suppliers, customers, personnel, and/or public utilities (e.g. gas, electricity). 

A preventive maintenance schedule is implemented for areas where it is most needed it is followed under normal Hrcumstances. Manufacturers and indnstry recommendations and consensns standards for maintenance freqnency are comphed with. Breakdown repairs for safety related items are expedited. Safety device checks are documented. Ventilation system function is observed periodically. 

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