Routine Maintenance Activities

Many engineers associate materials selection only with the design and construction of new facilities, plant additions, or plant renovations. However, it is also part of a plant s routine maintenance activities, being a subject of discussion between operations, planning, and maintenance personnel. Such discussions usually illustrate the need for both short-term and long-term solutions. 

Based on operating experience to date, the DAVINCH manufacturer states that about 30 minutes per day, an additional 3 hours per week, and still another 3 hours per month are required for routine maintenance activities. While these routine activities do not affect peak throughput, unscheduled corrective maintenance activities will probably take place over a 3 - to 6-year operating period and could reduce this throughput. 

Recommend excluding routine maintenance activities not generating dust from the formal policy. 

The design should ensure that routine maintenance activities are only required on an infrequ basis, can be pafixmed by local staff (with instructitxi from e)q)etts at a central support station, if necessary) and do not require high skill levels. 

Although not required by regulation for OS HA PSM and EPA RMP covered facilities, some companies are finding that PSSR for some routine maintenance activities can provide a return on investment. Certainly process safety and personnel safety benefit, but general quality and reliability issues are also avoided with a good PSSR program. 

Not all routine maintenance activities benefit from PSSR as much as others. For example, a company may choose to perform PSSR for a catalyst change, but may not choose to perform PSSR for routine pump replacements or rodding out heat exchanger tubes. The determination is open to facility management s discretion and is usually based on three aspects of the specific routine maintenance task. Scheduling a PSSR may need to be included in the work order. These are ... 

The use of automated work order cards is common throughout all hazardous industries. The BeUe plant phosgene accident shows the danger of over-reliance on these systems if a data error should occur, and an important routine maintenance activity gets accidentally dropped, how do engineers and managers know about it ... 

They are used during routine maintenance activities but with a low frequency (less than once every 6 months). 

No integrated program exists to ensure the availability and update of all the needed reference material, drawings, and manuals for planning and maintenance personnel. Pending the implementation of a process to provide the needed documents for routine maintenance activities, this remains an open item. 

Maintenance "indicators" are available to help facility staff determine when routine maintenance is required. For example, air filters are often neglected (sometimes due to reasons such as difficult access) and fail to receive maintenance at proper intervals. Installation of an inexpensive manometer, an instrument used to monitor the pressure loss across a filter bank, can give an immediate indication of filter condition without having to open the unit to visually observe the actual filter. Computerized systems are available that can prompt staff to carry out maintenance activities at the proper intervals. Some of these programs can be connected to building equipment so that a signal is transmitted to staff if a piece of equipment malfunctions. Individual areas can be monitored for temperature, air movement, humidity, and carbon dioxide, and new sensors are constantly entering the market. 

Simulation models aim to replicate the workings and logic of a real system by using statistical descriptions of the activities involved. For example, a line may run at an average rate of 1000 units per hour. If we assume that this is always the case, we lose the understanding of what happens when, say, there is a breakdown or a halt for routine maintenance. The effect of such a delay may be amplified (or absorbed) when we consider the effect on downstream units. 

Quality systems require that facilities and equipment should be appropriate to the activities undertaken. Surfaces that are easy to clean and maintain in hygienic condition are a requirement in many situations. For example, cloth-backed chairs would not be acceptable in a laboratory that handled potentially biohazardous materials. Equipment should be checked at installation to demonstrate that it can perform its desired function. This is frequently done using an Installation Qualification, Operational Qualification and Performance Qualification (IQ /OQ/PQ) commissioning process. Routine maintenance and calibration programmes are then required to ensure that equipment continues to deliver the specified performance. 

According to the vendor, the capital costs for the treatment system include a 200-actual cubic-feet-per-minute (ACFM) vacuum pump, two transfer pumps, a carbon steel knockout pot, and associated instrumentation and piping. Operation and maintenance costs for the system include estimates for additional granular activated carbon (GAC) units, liquid- and vapor-phase analysis, weekly monitoring, electricity, and routine maintenance. These costs vary, depending on the monitoring requirements, contaminant concentrations, and other variables (D13124Y, p. 492). 

Outside of the occasional system calibration and model verification tests, the routine maintenance burden of a Raman system is quite low. Optical windows may need to be cleaned, though automatic window cleaning systems can be implemented if it is a known issue. The most likely maintenance activity is laser replacement. Some systems have a backup laser that turns on automatically if the primary laser fails. This lessens the impact of a failure if the unit is being used for closed-loop process control. With a quality instrument and well-developed models, process Raman installations need less maintenance than many competing techniques. 

Within a typical world-class industrial commodity chemical company the annual cost of maintenance is 3 to 6 percent of the asset replacement costs. A number of significant maintenance activities require very little interruption of continuously operating chemical plants. Everyday maintenance activities that may be accomplished on a routine basis include repairs to a spare pump or spare compressor after it has been properly isolated and cleared of fluids, and overhaul of a fully spared filter or painting. 

Routine repair and maintenance activities should be embodied in approved SOPs. Instrumentation, computer hardware elements, and communication network components should all be covered. The following areas should be addressed ... 

The whole project development environment must be routinely backed up during development phase and archived at the end of the development to enable reconstruction of the development environment so that it facilitates subsequent maintenance activities and disaster recovery. 

Standard Operating Procedures (SOPs), all routine operational and maintenance activities Documentation Requirements... 

Volatile compounds exhibit high activity coefficients in water and are easily evaporated. The countercurrent air stripper provides a large wetted surface area for mass transfer in a compact unit. Although routine maintenance is required, the components of the air stripper should have long service lives. The air stripper is capable of removing large numbers of volatile compounds at relatively low cost. 

LP-4 is a high-level active protection that can detect to treat, detect to mitigate, or detect to warn and protect. LP-4 includes rapid, automated systems. LP-4 eliminates the human decision factor, but the complex and sophisticated automated systems require routine maintenance to ensure their proper... 

Two groups of airmen were enrolled. Those designated as JP8 exposed consisted of active duty Air Force personnel who routinely worked with or are exposed to JP8 in the performance of their duties. Most exposed volunteers worked in Aircraft Fuel Cell Maintenance shops. These workers routinely performed maintenance activities requiring entry into aircraft fuel tanks. Other exposed volunteers worked in either the Fuels Specialty or Fuels Transportation shops. In order to qualify for the study, exposed volunteers were required to have least 9 months of persistent exposure to jet fuel (such as fuel tank entry at least one hour twice weekly). 

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