ASME EA-1G:2010 pdf free download

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ASME EA-1G:2010 pdf free download

ASME EA-1G:2010 pdf free download.Guidance for ASME EA-1, Energy Assessment for Process Heating Systems.
Additional information on flue gas measurement can be obtained from books such as reference 191 in Nonmandatory Appendix A.
(d) Pressure and Flow Measurements. For combustion air and fuel gas pressures, a measuring range up to 2 psig (55 in. water column or w.c.) is usually sufficient. Fuel oil and compressed air and steam pressures for atomizing may range up to 100 psig or higher. Internal pressures in ovens and furnaces are usually a few tenths of an inch w.c. positive or negative, requiring a resolution in hundredths of an inch w.c. Inexpensive pressure gauges are readily available but generally should be avoided unless they have been specifically calibrated for the assessment. Liquid-filled manometers have the highest inherent accuracy but may be cumbersome to use. Digital electronic manometers are more convenient to use and easier to read but should be calibrated against a reliable standard because of their tendency to drift over time. Figure 2 shows a general selection guide for pressure measurement in process heating systems.
For combustion air and fuel gas flows, orifice meters are commonly used. For smaller flows, such as fuel gases, a rotary meter can be used. If these instrunwnts are not already present, considerable effort will be required to install them. This installation has to be done prior to assessment activities. As an alternative, the air and sometimes the gas flows to burners can be derived from static pressure measurements at or close to the burners. Most manufacturers provide pressure taps for this purpose, and flows can be determined from calibration charts or tables provided with the burners.
Flue gas flow measurements can be carried out with pitot-static tubes or similar flow-measuring devices, together with a manometer to measure differential pressures in the range of a few inches of water column. liquid flows can be measured by rotary meters or clamp-on type flow meters and may require preparation for their use.
Process gas flows (such as nitrogen) in small volumes(usually less than a few thousand cubic feet per hour)can be measured by using rotameters or flow scopes.Condensable fluid vapors such as steam can be measuredby orifice meters, provided the vapors do not condense inthe lines upstream and downstream near the orifice meter.In some cases, flows of liquids, vapors, and gases can alsobe measured with ultrasonic metering systems.Severalnew types of flow-measuring devices are being promoted,and they should be considered on a case-by-case basis.Flow readings, particularly for gases (natural gas, air,etc.) should always be corrected to account for pressureand temperature of the fluid being measured.These cor-rections can be used to express flow rates at predefinedstandard conditions or at the desired operating (temper-ature and pressure) conditions.
Figure 3 shows a general selection guide for flowmeasurement methods in process heating systems.