External services component

The external services component links the environmental scanning for complementary services and added-value components, and are based on the customer-requested solution plotted. 

The fact that a component should not be modified does not mean that it cannot be customized externally. A component can be designed to provide, in addition to the interfaces for its primary services, additional interfaces for plug-ins that customize the behaviors of its primary services settable properties are a special case of this. This style of pluggable design is discussed in Chapter 11. 

The changes described above also allowed much easier access to the high voltage cable for routine (6-month) owner directed, service operations, and provided better upper and lower x-ray cabinet and control cabinet ventilation. With the exception of the x-ray tubes, all the individual manufactured components, on all four systems are identical. There are very subtle differences in the warm-up/start-up sequence on the x-ray controllers on the newer systems due to model/year and x-ray tube differences. The last three systems were supplied with environmental type key-boards for the image processors and base-mounted , rather than conduit-mounted exterior warning indicators. The first system was subsequently upgraded to include the better keyboard and the external warning appliances/features. 

Traditionally, customers employ water treatment service companies simply as external contractors to assist in the maintenance of clean and efficient waterside surfaces in their various heating, steam generating, cooling, and certain industrial process systems. The customers benefit from genuine improvements in operating efficiency, reductions in maintenance time, and replacement component costs. In addition, where industrial processes are involved they often profit from an added-value, due to an improved product quality or reduction in manufacturing cost. 

In this external contractor role, water treatment companies providing technical application and problem solving services are required to possess some general design component and process operating knowledge... 

For one component to replace another, the replacement component need not work the same internally. However, the replacement component must provide at least the services that the environment expects of the original and must expect no more than the services the environment provides the original. The replacement must exhibit the same external behavior, including quality requirements such as performance and resource consumption. 

Abstraction, along with encapsulation, is a technique that hides the internal structure and implementation details of an object or some other software unit with its external interfaces. In this chapter, I focus on objects. Other software units include components, subsystems, and services. They will be discussed in subsequent chapters. Abstraction is about what a software module looks like to the outside world. Encapsulation uses these looks to hide the module s implementation details. At first glance, abstraction may not sound like a big deal. Quite the opposite, a system with well-designed abstractions greatly reduces couplings between its building blocks and is much easier to understand, maintain, and extend. Because highly coupled software systems... 

A high-voltage variable speed motor will usually drive an important pump or compressor which must remain in a serviceable condition, and not be subject to lengthy shut downs due to poor performance or serious failure of its major components. Modem systems will usually contain a micro-computer to process alarms, to give visual information, to communicate to external facilities and to safely shut down the system in the event of a serious or progressive fault being detected. 

Most stress corrosion service failures occur from the influence of residual stresses. These arise during component manufacture, and plant assembly, including welding. In laboratory work the stress is usually applied externally since it is then much easier to control and measure. The oldest and simplest test is to measure how long a specimen takes to break — the time-to-failure, tf. Typical specimens might be loaded in tension and surrounded by the corrodent or bent into a U, clamped and then immersed. Typically, the value t varies as shown in Figure 1. Two points can be made. First, the tf changes less markedly at stresses above the 0.1X proof stress than below it. Secondly, it is not always clear whether a threshold stress exists below which stress corrosion failures will not occur. This is of obvious importcuice but it has proved a... 

Output view This view contains all physical and nonphysical output that is created by business functions, including services, materials, and products as well as funds flows. Because each output is input for another function—even if this function is probably carried out by an external partner—input-output diagrams are also components of this view. 

This function includes all information about the operational status and maintenance of equipment, vehicles, and facilities. Operational status refers to an availability state (in active service, ready, standby, in/awaiting maintenance, etc.), along with total time in service, time since last regular maintenance, and so on. The ERP system tracks maintenance schedules for the equipment and actual maintenance incidents, both preventive and remedial, and typically an attention list of things that may need inspection and refit. Any maintenance activities include both technical data (nature of fault, repair or change, parts installed, named services performed, etc.) and administrative data (authorization, execution team, date and time, etc.). In addition, this component tracks the schedules, labor, and work assignments of maintenance teams, external maintenance contracts and calls, and actual or assigned costs of maintenance activities. 

Cryogenic fuel tanks are essential components for space transportation systems. Materials for cryogenic fuel tanks must safely carry pressure, external structural loads, resist leakage, and operate over an extremely wide temperature range. Aramids exhibit a wide range in service temperature and are therefore candidates for such applications. A wide variety of skin and core materials have been tested for helium gas permeability. It turned out that Nomex is superior in comparison to Kevlar . A low level of permeability could be achieved, which meets the requirements. 

Corrosion resistance in subsea environments is of prime importance, as FPSO s are constructed in open water to facilitate mooring tankers at offshore oil and gas exploration stations without jetties and breakwaters. Unlike bronze components, which can develop severe galvanic corrosion, PEEK bearings and thrust washers provide longterm corrosion resistance and superior wear resistance. PEEK compoimd requires no external lubrication, another key advantage in this application. Bronze bearings and thrust washers are subject to premature wear and reduced service life should they run dry. (Victrex pic, Victrex Tech. Ctr., Hillhouse Int L, Thornton Cleveleys, Lancashire FY5 4QD, UK Phone +44—1253-897700 URL www. victrex.com). 

Both TS and TP compounds have many applications in electrical appliances and electronics products, both as internal components and as external housings (Figure 6.26). The choice between the two groups of materials depends largely on size and service temperature. Processes used are primarily injection molding and compression molding. 

The use of stainless steel in oil production has increased, and is of particular significance for production in deep waters. This applies both to production and process equipment carrying oil and gas and to seawater systems. For seawater systems the experience from nuclear power plants has been useful. In these plants, some high-alloy steels have performed well in equipments such as seawater pumps and heat exchangers. But the performance depends on service conditions, design and combination of materials. On the oil/gas side, good experience has been obtained with 13% Cr steel in production tubing, in components at the wellhead and in well valves. The same can be said about the use of other stainless steels in process systems offshore, but there have been some exceptions. For instance, SCC has occurred on duplex steel (22-5-3) under external heat insulation (compare Section 7.12) [10.11]. 

Corrosion in oil and gas service can be classified into two categories internal corrosion and external corrosion. Internal corrosion is primarily due to the corrosive components present in the fluids handled by the particular oil and gas asset. External corrosion, on the other hand, occurs when the asset interacts with its surrounding environment. For example, in a subsea pipeline, internal corrosion is attributed to the corrosive fluids transported by the pipeline, whereas external corrosion occurs when the pipeline is attacked by the surrounding seawater. The nature and extent of damage caused by internal and external factors are highly dependent upon the chemical and physical attributes of the operating conditions. Chemical attributes are described by the various contaminants in the... 

Structural quality shapes and plate (ASTM 36) usually provide satisfactory service for external furnace supports, shells, and external conveyor and walking beam components (see figure 9.13.)... 

Analysis and mechanical tests in-service surveU-lance for irradiation effects fracture toughness tests (12.5 mm compact tension specimens or thicker) for quahty control of components and qualification of welding procedures low temperature irradiation effects on external vessel supports. 

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