Scheduled downtime

One of the manufacturing challenges with a full-system cleanout, is the need to interrupt manufacturing. Some fabs have installed totally redundant delivery systems, including dispense module and piping. Some adopt a scheduled downtime for system maintenance. Most simply refuse to recognize the need until disaster strikes in the form of unscheduled interruption of slurry delivery or dramatic increase in wafer defects. 

Simply stated, OEE measures the plant s performance compared to the theoretical maximum production rate for the assets. It is a powerful metric that gives management an overall look at production effectiveness and eliminates the practice of hiding reliability shortcomings into scheduled downtime. 

It is also possible to define availability in terms of total time, without taking any credit for scheduled downtime. Using the same sample data, the availability of the system in this case becomes ... 

Operating schedule—continuous or intermittent. Scheduled downtimes for maintenance, vacations, other... 

Finally, the third limitation of predictive maintenance in process machinery is that downtime must be scheduled to allow for inspection of the equipment, which in itself poses risk. It is not an exaggeration to say that the source of the majority of equipment failures, which were studied, began shortly after predictive maintenance inspections made disassembly of equipment necessary. Figure 62.2 shows how trouble incident frequencies can increase contrary to expectations after inspection and overhaul. 

Plant reliability problems are associated with excessive downtimes due to component failure or scheduled maintenance requirement. Development needs include ... 

Hardware must be maintained, tested, and cleaned on a schedule that will minimize downtime and problems due to data loss or corruption. 

Firing of Enamels. Firing can be carried out in intermittent box-type furnaces or continuous furnaces. The dryer and the furnace form one continuous unit or function as separate units in the continuous firing process. Most industrial furnaces are fiber-lined (low thermal mass), which lowers cost and downtime between firing schedules. 

Regardless of the age or cost of information and hardware systems, all require some form of maintenance. Maintenance involves updating, changing, or improving the existing system. The goal is to continually improve the systems functionality and usability while minimizing the time that it is nonoperational (downtime). Ideally, information systems should require only minor or routinely scheduled maintenance. There are two kinds of maintenance or downtime scheduled... 

The EZ-Track system collects data on cycle times, cycle/part counts, and number of rejects, and it uses this data as the foundation to perform powerful scheduling tasks. The EZ-Track scheduler can check for mold conflicts and machine feasibility and highlight any problems, as well as continuously update estimates of job completion times based on actual cycle time, downtime, rejects, and cavitation. In addition, the scheduler also supports family molds. 

Equipment should be demagnetized periodically — e.g., during scheduled maintenance downtime — according to the manufacturer s instructions. This is a time-consuming process, and requires disassembly and reassembly of the unit. Magnetism can be minimized by applying brushes to the... 

The estimated cost of the pipes, per unit length is schedule 40 carbon steel 5, schedule 80 carbon steel 8.3, stainless steel (304) schedule 40 24.8. Installation and fittings for all the materials adds 16.5 per unit length. The downtime required to replace the pipe does not result in a loss of production. 

One problem the Johnston Atoll facility did experience was some schedule slippage because of maintenance downtime. This was due to technical and mechanical problems with various equipment and the need for more training of certain personnel. These problems did not affect the Army s ability to destroy or decontaminate chemical weapons within EPA s standards—-just the rate at which destruction occurred. 

Camera approach Directly observe the waterwall to find steam leaks and qualify them to determine whether or not the boiler can continue to operate until the scheduled outage, avoiding downtime that could cost hundreds of thousands of dollars. 

What works best for pitta types is flexibility in routine, with plenty of built-in downtime. Pitta people also need to make sure theyVe scheduled activities or periods when their focus is on being thoughtful and attentive to others, to get them out of a focus on themselves. 

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