Installation of flexibility

A flexible hose must never be stretched tightly between two fittings. About 5 to 8 per cent of the total length must be allowed as slack to provide freedom of movement under pressure. When under pressure, flexible hose contracts in length and expands in diameter. Examples of correct and incorrect installations of flexible hose are illustrated in Figure 40.33. 

Figure 40.33 Correct and incorrect installation of flexible hose...

ISO/TR 10465-1 1993 Underground installation of flexible glass-reinforced thermosetting resin (GRP) pipes - Part 1 Installation procedures. 

Stability, fluid compatibility and fatigue resistance also are associated with wear resistance. Vibration and pulsation in mechanical systems, or pipelines are common in chemical process industries and can lead to leakages of corrosive fluid. The vibration fatigue is an unavoidable factor which is further aggravated by improper installation of the moving system. Leakages due to these pulsations can be prevented by the installation of flexible rubber expansion joints. 

It is common practice to support the fan on anti-vibration mountings and connect the fan casing to the duct by short lengths of flexible non-combustible material. Care should be taken during installation to see that these are aligned to prevent entry turbulence and noise generation. 

The minimum bend radius for flexible hose varies according to the size and construction of the hose and the pressure under which the system operates. Current applicable technical publications contain tables and graphs showing the minimum bend radii for the different types of installations. Bends that are too sharp will reduce the bursting pressure of flexible hose considerably below its rated valve. 

This section is an overview of flexible drive chains and sprockets. It provides the basic knowledge required to install, operate, and service this means of power transmission. 

Additional fluid-lift capability was planned through a combination of increased gas-lift capacity and installation of submersible pumps. Gas-lift system expansion was critical for future flexibility of the system to allow target production rate modifications on the basis of reservoir performance. Most field gaslift compressors used to supplement plant compression were to be shut in as soon as gas-lift system expansions were completed. 

Increases in reservoir fluid withdrawal and redistribution of fluid production patterns required the construction of four new disposal stations, expansion of four existing stations, and installation of 7 miles (11.3 km) of pipeline to provide connections and flexibility between the systems. Smaller disposal facilities in remote areas of the Field were shut in as connections were completed. 

The osmium methodology provides a great deal of flexibility for the functionalization of carbons 4-7 in the indole ring. For example, substitution on carbons 4 and 5 originates from the choice of ketones in the initial aldol reaction, or from substitution installed on the P-vinylpyrrole complex during the acylation or Michael addition steps. Functionalization on carbons 6 and 7 depends on the choice of dienophile. This overall... 

Flexible thin-film solar cell strips and collectors are also available. Figure 1.34 illustrates the rooftop installation of solar shingles developed by the National Renewable Energy Laboratory (NREL). U.S. Department of Energy s NREL reported in March 2008 that their researchers created a world record in efficiency for thin-film solar cells (19.9%), nearly tieing the record for traditional photovoltaics (20.3%). Thin cells require less expensive materials to build and use less of them. This results in a substantial cost reduction. 

The data reduction hardware is based on a Hewlett-Packard 9825A desk top computer. It is supported by one megabyte of flexible disk storage, a printer/plotter and the necessary interface equipment for on-line LSC data collection. Reliability was a prime factor when the hardware was chosen. The LSC(s) and data system run virtually unattended, 24 hours a day, 365 days a year. Samples are typically counted for two minutes each plus one minute for the external standard. Therefore, data from the four counters are received by the HP9825A at an average interval of 45 seconds. With such a demand on the system, computers require good service support, more so than other instruments. Since installation in May, 1977, there have been less than two work days of cumulative downtime. 

General comments Recent trend has favoured building of pelletization plants due to chemical and physical uniformity of product. However, because of flexibility of sintering process and its ability to treat many different materials without fine grinding, both types of agglomeration appear to have a definite place in future installations ... 

The bracket construction permits support of the exchanger without fixing the supports to the shell. This provides for thermal movement of the shells within the brackets and prevents the transfer of thermal stresses into the process piping. In special cases the brackets may be welded to the shell. However, this is usually avoided due to the resulting loss of flexibility in field installation and equipment reuse at other sites and an increase in piping stresses. 

Chemical resistance. Unmodified epoxy resins have excellent resistance to dilute acids, alkalis and certain solvents. The incorporation of an LP component into the epoxy resin extends this resistance to a wide variety of oils, aromatic and aliphatic hydrocarbons, esters and ketones. Coatings and adhesives based on polysulphide-epoxy resins exhibit reduced swell and maintenance of flexibility and adhesion when immersed in these fluids. In view of this, LP-modified epoxies are used on oilrigs, fuel-storage installations and chemical plants (Figure 10.4). 

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