Utility piping systems steam

Pipe used for low-pressure applications such as transporting air, steam, gas, water, oil, etc. Employed in machinery, buildings, sprinkler and irrigation systems, and water wells but not in utility distribution systems can transport fluids at elevated temperatures and pressures not subjected to external heat applications. Fabricated in standard diameters and wall thicknesses to ASTM specifications, its diameters range from Vs to 42 in. o.d. 

The main arterial system of a plant is yard piping. It is here that long process lines are located interconnecting distant equipment with lines entering and leaving the unit. Also located in the yard are utility headers supplying steam, air, gas, and water to process equipment. Here are located all relief and blow-down headers. Often instrument lines and electrical supply conduits are also supported on the yard steel. 

Steam—Primarily utilized for systems composed of closed vessels, with interconnecting piping. It has some similarity to empty chamber studies in steam sterilizers. Important parameters to confirm are appropriate time-temperature conditions throughout the system. Emphasis is placed on the removal of air and condensate from the system, strict adherence to the defined sequence for the sterilization procedure and inclusion of methods for the protection of the system between sterilization and use. 

On chemical plants and oil refineries, steam, nitrogen, compressed air. lubricating oil, and other utility systems are responsible for a disproportionately large number of accidents. Flammable oils are recognized as a hazard, but services are given less attention. If the modification to the lubricating system had been systematically studied before it was made, as recommended in Chapter 2, a larger vent could have been installed, or a pipe-break and funnel could have been installed at the inlet to the sump. 

In an efficient and economical steam system, this so-called flash steam will be utilized on any load that can make use of low-pressure steam. Sometimes it can be simply piped into a low-pressure distribution main for general use. The ideal is to have a greater demand for low-pressure steam at all times than the available supply of flash steam. Only as a last resort should flash steam be vented to atmosphere and lost. 

Confirmed design in which additional detail and costs are developed for the arrangement of equipment, piping, utilities (water, steam, electrical, air), instrumentation, and control systems. 

Make specific allowances for distribution systems within the process area for the various utilities cooling water, high/low pressure steam/condensate, service water/air, nitrogen, instrument air, vent collection systems, etc. Lengths and sizes must be determined based on arrangement and flows. Allow at least 30 ft. of pipe from distribution system to each individual user. 

A packaged system is one that includes all necessary (and possibly some unnecessary) components - supports, piping, vessel(s), Instrumentation, process controls, and simplified access to local utilities of electric power, compressed air, steam, and water drains. Such a system is likely purchased (or possibly rented) from the supplier of activated carbon Some refer to this as a "turn-key" system, in that all the user has to do is "turn the key" and start operation. 

In addition to the feed water and inlet and outlet piping normally found in a reactor, the start-up system consists of a steam drum, a heat exchanger, and circulating pump, as shown in Fig. 8.17. The function of the steam drum is to provide a liquid level at which pressure equilibrium can be established based on the temperature of the water. Because no steam is allowed to escape the system, the system pressure is at the saturation temperature of the liquid. The function of the heat exchanger is to limit the coolant temperature being returned to the reactor to 350°C, and it is utilized in the start-up sequence... 

Many utilities must survive a catastrophic event such as a major explosion or fire so that emergency response systems continue to function. Yet such an incident can destroy critical utilities header containing electrical cables, cooling water hnes, and steam pipes. This is a very serious common cause effect that can trigger domino events that lead to a major catastrophe. The effect is magnified if emergency systems such as the firewater header are also damaged. 

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