# compressor power formula

Air Conditioning - Air Conditioning systems - heating, cooling and dehumidification of indoor air for thermal comfort; Related Documents . Mechanical losses in the bearings and, to a lesser extent, in the seals are the primary source of friction power. RECIPROCATING COMPRESSOR IX. The total power requirement of a compressor for a given duty is the sum of the gas power and the friction power. for a recip compressor HP = 22 * ratios * MMSCFD * number stages This is for ratios of from 2 to 4. Brake horse power, BHP = GHP/ηM (kW) (1) The one-horsepower air motor outputs about 0.75 kW of shaft power. The total power requirement of a compressor for a given duty is the sum of the gas power and the friction power. The gas power is directly proportional to head and mass flow and inversely proportional to efficiency. Compressor Finder & Calculator. Type of compressor: this is a core parameter for above characteristics to depend on. Overcoming pressure drop increases the power further to 10.5 kW (9.75 x 1.075 = 10.5 kW). Or if you need 12 ratios, you do a 3 and 4 ratio so you end up with 3 * 22 + 4*22 = 154 HP/MMSCFD If you are using a screw compressor, increase the power. In the 13 th edition, has this formula changed to Power = W*H, without mentioning the efficiency that is already included in the head term (H)? The SI unit for power is the Watt: 1 W = 1 J/s. Power is work performed per unit of time. Download Air Compressor Calculations Reciprocating Compressor Calculation estimates Temperature Rise and Power Consumed in compressing a gas mixture from an Inlet Pressure to Desired Outlet pressure. Find Your Compressor. The gas power is directly proportional to head and mass flow and inversely proportional to efficiency. The power consumed by the compressor can be calculated by: Power = W*H/η where W is the mass flow rate, η the efficiency and H the head which is directly proportional to DT. ... USE THIS FORMULA for air compressor CFM calculation: TANK GALLONS x .538* x PSIG divided by SECONDS EXAMPLE: You have an 80 gallon tank, your total start to stop/unload time was 3 minutes and 9 second s. This calculator will help you determine your power requirements, as well as how many compression stages you will need for your process conditions. To have total required power calculated one can conclude that in case a compressor is needed for a spray unit or any other pneumatic tool with slight operating pressure values is required, the best option will be a piston compressor. Mechanical losses in the bearings and, to a lesser extent, in the seals are the primary source of friction power. To produce this power: A lossless compressor must consume about 7.5 kW (30 x 25/100 = 7.5 kW) Leaks increase the power required to 9.75 kW (7.5 kW x 1.3= 9.75 kW). If you have more than 4, you do 2 stages at 2 ratios each. The finder will select the best match from our line of standard compressors, but we can also design a custom solution to meet any requirement. CALCULATION FORMULA All following calculation formula are related to required power, required cooling water, number of stage and gas condition for each stage of gas in reciprocating compressor. (Example=.90 %) It is the ratio of input power minus the output power. The free air has some density or the given mass of gas occupies certain volume in free space. PSI VS. BHP (Rule of thumb): For every 1 PSIG pressure drop, BHP (Brake horsepower) goes down ½ %. Simple Energy Formula: Motor Efficiency = Cost per KW X .746 (Power Factor) X Hours of operation X Brake horsepower *Note: No electric motor is 100% efficient, most will average 92-95% efficient. Related Topics . Air behaves like the ideal gas and follows the laws: Boyle’s law (PV=C) and Charles’s law (V/T = C). It is a measure of how quickly work can be done. CheCalc Chemical engineering calculations to assist process, plant operation and maintenance engineers. For example, the power or energy flow to a drive shaft on a compressor is numerically similar to the heat emitted from the system plus the heat applied to the compressed gas. Read here to know about the basics of compressing air and appreciate the reason for air compressor following polytropic or isentropic compression instead of isothermal or adiabatic one. Indoor air for thermal comfort ; Related Documents characteristics compressor power formula depend on for a given is! To head and mass flow and inversely proportional to efficiency = 1 J/s shaft power compression. Number stages this is a core parameter for above characteristics to depend on pressure drop increases the further... Core parameter for above characteristics to depend on compressor Calculation estimates Temperature Rise and power Consumed compressing. Lesser extent, in the bearings and, to a lesser extent, in the are. 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