Maintenance issues

System hygiene and cleanliness, and maintenance issues General requirements presented in ENV 12097 and prEN 13779 apply. 

These are a few of the mechanical factors that have much more effect on the electronic design of motion control systems. The electronic engineer must understand the mechanics of motion that are encountered in order for the electronic system to be successful. To decide on electronic and software requirements, it is important factors have to be considered such as product flow and throughput, operator requirements, and maintenance issues. 

Agent Hydrolysis and Treatment of Metal Parts (Steps 8, 10, 13, and 16), 115 Treatment of Hydrolysates and Dunnage by Supercritical Water Oxidation (Steps 11, 12, and 14), 116 Assessment of Integration Issues, 118 Component Integration, 118 Process Operability, 119 Monitoring and Control Strategy, 119 Maintenance Issues, 119 Process Safety, 120 Worker Health and Safety, 121 Public Safety, 121... 

Maintenance issues are important to address, and the requirement for high cost replacement parts must be kept to a minimum, unless the frequency of replacement is once every three to four years. Today, process FUR analyzers are not necessarily a problem, as long as components are simple to replace. The normal replacement items are the somce and laser, and the replacement of these must be kept simple. If an interferometer alignment is required, then this must be automated via an integrated mechanized auto-align procedme. 

Instead of replacing the air filters every three days as prescribed, it was, in reality, necessary to replace the filters every three hours. To perform maintenance every three hours is an unreasonable expectation— it is hard enough to do during the day, but it would also require a soldier to wake up multiple times in the middle of the night. Clearly, maintenance issues are equally critical to the usefulness of the instrument as is ensuring it works properly in the first place. 

The mathematical model demonstrates the importance of sample collection (r/T), preconcentration (tjc), concentration (C), and detection (k) in a complete trace portal detection system. Of these three subsystems, the detector is the most understood. Considerable information is available that quantifies the sensitivity, specificity, and limits of detection (LOD) for a particular detection method when used for trace explosives detection [13-15], For trace detection portals, the selection of the detection method is based on performance, initial cost, and maintenance issues. The remaining subsystems (sample collection and preconcentration) are the most variable and least understood for their contribution to trace portal performance. Optimizing the explosive removal and transport in sample collection along with preconcentration will enhance the performance of the entire trace detection system. The sensitivity of the detector will help determine the performance needed from the sample collection and preconcentration. 

This chapter can be summarized using excerpts from a recent paper by the U.S. Chemical Safety and Hazard Investigation Board (CSB) presented at the 37th AIChE Loss Prevention Symposium. Stephen J. Wallace presented a paper entitled, Know When to Say When. A Review of Safety Incidents Involving Maintenance Issues. [30] Stephen Wallace and Carolyn Merritt s paper utilized information from six published CSB investigations and recognized that maintenance activities can introduce hazards or exacerbate existing hazards. 

Wallace, Stephen and Carolyn Merritt, Know When to Say When A Review of Safety Incidents Involving Maintenance Issues, Process Safety Progress, Dec. 2003, pp. 212-219. 

CLEAN-FACILITY DESIGN, CONSTRUCTION, AND MAINTENANCE ISSUES... 

Raymond K. Schneider, Clemson University, Clemson, South Carolina, Clean-Facility Design, Construction, and Maintenance Issues... 

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