Installation Piping

TABLE 9-57 Components of Total Installed Piping Cost... 

Pressure Testing Prior to initial operation, installed piping shall be pressure-tested to assure tightness except as permitted for Category D fluid service described later. The pressure test shall be maintained for a sufficient time to determine the presence of any leaks but not less than 10 min. 

The length of installed pipe between the ignition source and the flame arrester is critical to the proper performance of end-of-line and in-line deflagration flame arresters. Line lengths greater than those used in the test allow higher flame speeds and pressure to... 

It is not permissible to install an installation pipe in an unventilated shaft, void or duct (Regulation 18(5) of the Gas Safety (Installation and Use) Regulations). 

Piping should easily fit the compressor connections without needing to spring or twist it to fit. It must be supported independently of the compressor and anchored, as necessary, to limit vibration and to prevent expansion strains. Improperly installed piping may distort or pull the compressor s cylinders or casing out of alignment. 

The accuracy and reliability of an estimate can be improved by dividing the process into sub-units and using factors that depend on the function of the sub-units see Guthrie (1969). In Guthrie s detailed method of cost estimation the installation, piping and... 

Do not install pipes in pits, trenches, or depressions where water can accumulate. 

Integrity Assurances - When first installed piping systems will be checked for leakages at weld joints and flange connections. Weld joints are usually verified by NDT radioactive means (i.e., x-ray) or die penetrants. 

The pipe diameter for the main distribution lines should be hydraulically sized based on projected flow and pressure demand, but in no case less than 8 in (20 cm). Larger line sizes should be considered when there is a possibility of facility expansion. Typically the cost of installing pipe is mostly excavation cost. Increasing line size is insignificant when compared to the total cost of the project. Lines terminating at hydrants, monitors, and other protective systems should be at least 6 in (15 cm) in diameter. 

Fixed systems are complete installations piped from a central foam station to tanks or equipment, discharging through fixed delivery outlets. These outlets take the form of foam chambers, monitor nozzles, foam-water spray nozzles, etc. Any required pumps are permanently installed. 

Study estimate also called factored estimate . When studies are more advanced, the factored estimate may take into account the detailed equipment characteristics. Once the individual costs are determined, they may be multiplied by a number of factors for installation, piping and services, instrumentation and control and eventually by date and geographic location factors. Probable accuracy of estimate is about +25-30%. 

Once the purchased equipment costs are known, the capital investment can be calculated by summing these results and using ratio factors for installation, piping, buildings, instrumentation, electric equipment, thermal isolation, indirect expenses, etc. (Chauvel, 2000). 

The annual cost for the installed piping system may be expressed as... 

Kf = annual fixed charges including maintenance, expressed as a fraction of initial cost for completely installed pipe... 

Install conduit, wiring, and junction boxes Instruments and J.B. connections Multi-conductor cable to terminal panel Terminal panel and TDC console connection Instrumentation - Air Hookup Install pipe Support pipe Hook up... 

To improve the corrosion resistance of the stainless steel components, particularly in the weld-affected areas, it is a common practice to passivate the product contact surfaces of installed piping and equipment by circulating a solution of strong oxidant such as nitric or citric acid, or a chelating agent. Passivation removes free iron from the metal surface and creates a thin protective layer of chromium oxide. It is not uncommon to repeat the passivation treatment periodically (every few years) to restore the passive layer. 

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