Engineering Guide - Intellishare

1 EngineeringGuideECLIPSE COMBUSTIONENGINEERING GUIDEP ublished byEclipse, 1986byEclipse, Elmwood RoadRockford,Illlinois 61103 All Rights EditionEFE-825, 8/04 Printed in the United States of AmericaCONTENTS1. Orifices & FlowsCoefficients of Discharge for Various Types of Orifices .. 4 Orifice Flow Formulas .. 4 Orifice Capacity Tables, Low Pressure Gas .. 5 Orifice Capacity Tables, High Pressure Gas .. 9 Piping Pressures Losses, Air .. 12 Piping Pressure Losses, Natural Gas .. 13 High Pressure (Compressible) Flow of Natural Gas in Pipes .. 14 Equivalent Lengths of Standard Pipe Fittings & Valves .. 14 Simplified Selection of Air, Gas and Mixture Piping Size .. 15 Quick Method for Sizing Air Piping .. 15 Sizing Branch Piping by the Equal Area Method.

2 16 CvFlow Factor Conversion .. 16 Duct Velocity & Flow Measurement .. 172. Fan Laws & Blower Application EngineeringTheoretical Flow .. 18 Fan Laws .. 19 Blower Horsepower Requirements .. 20 Blowers Used as Suction Fans .. 20 The Effect of Pressure on Air .. 20 The Effect of Altitude on Air .. 20 The Effect of Temperature on Air .. 213. GasPhysical Properties of Commercial Fuel Gases .. 22 Combustion Properties of Commercial Fuel GasesAir/Gas Ratio, Flammability Limits, Ignition Temperature & Flame Velocity .. 22 Heating Value, Heat Release & Flame Temperature .. 23 Combustion Products & CO2 .. 23 Equivalent Propane/Air & Butane/Air Btu Tables .. 24 Propane/Air & Butane/Air Mixture Specifications.

3 244. OilFuel Oil Specifications Per ANSI/ASTM D 396-79 .. 25 Typical Properities of Commercial Fuel Oils in the .. 26 Fuel Oil Viscosity Conversions .. 26 API Vs. Oil Specific Gravity & Gross Heating Value .. 27 Oil Piping Pressure Losses .. 27 Oil Temperature Drop in F Per 100 Foot of Pipe .. 295. Steam & WaterBoiler Terminology & Conversion Factors .. 30 Properties of Saturated Steam .. 30 Btu/Hr. Required to Generate One Boiler .. 31 Sizing Water Piping .. 31 Sizing Steam Piping .. 3126. Electrical DataElectrical Formulas ..33 Electrical Wire Dimensions & Ratings ..33 NEMA Size Starters for Motors .. 33 NEMA Enclosures .. 34 Electric Motors Full Load Current, Amperes .. 347.

4 Process HeatingHeat Balances Determining the Heat Needs of Furnaces and Ovens .. 35 Thermal Properties of Various Materials ..37 Thermal Capacities of Metals & Alloys .. 40 Industrial Heating Operations Temperature & Heat Requirements .. 41 Crucibles for Metal Melting Dimensions & Capacities .. 43 Radiant Tubes Sizing & Input Data .. 43 Heat Losses, Heat Storage & Cold Face Temperatures Refractory Walls . 44 Air Heating & Fume Incineration Heat RequirementsUsing Raw Gas Burners .. 45 Using Burners with Separate Combustion Air Sources .. 45 Fume Incineration Selection & Sizing Guidelines .. 46 Liquid Heating Burner Sizing Guidelines .. 47 Black Body Radiation .. 49 Thermocouple Data .. 49 Orton Standard Pyrometric Cone Temperature Equivalents.

5 508. Combustion DataAvailable Heat for Birmingham Natural Gas .. 51 Available Heat for Various Fuel Gases .. 51 Flue Gas Analysis Chart .. 52 Theoretical Flame Tip Temperature vs. Excess Air .. 52 Heat Transfer Relationships .. 52 Thermal Head & Cold Air Infiltration into Furnaces .. 53 Furnace Flue Sizing .. 539. Mechanical DataDimensional and Capacity Data Schedule 40 Pipe .. 54 Dimensions of Malleable Iron Threaded Fittings .. 55 Sheet Metal Gauges & Weights .. 56 Steel Wire Gauges & Weights .. 56 Circumferences & Areas of Circles .. 57 Drill Size Data .. 59 Tap Drill Sizes .. 60 Drilling Templates Pipe Flanges .. 6010. Abbreviations & SymbolsAbbreviations .. 61 Electrical Symbols .. 6211. Conversion FactorsGeneral Conversion Factors.

6 64 Temperature Conversions .. 68 Pressure Conversions .. 69 Index ..72 Tech NotesTable of Contents ..7334 The flow of air or gas through an orifice can be determinedby the formulaQ = x Ax Cdhgwhere Q=flow, cfhA=area of the orifice, sq. in. (see Pages 57 & 58)Cd=discharge coefficient of the orifice(see above)h=pressure drop across the orifice, gravity of the gas, based on standardair at (see Pages 19, 20, & 22 thru 24.) Orifice PlatesTo calculate the size of an orifice plate, this equation canbe rearranged as follows:A= x of Changes in Operating Conditions onFlow through an Orifice General RelationshipQ2=A2xCd2xh2xg1Q1A1Cd1h1g2If any of the factors in this relationship remain constantfrom Condition 1 to Condition 2, they can be dropped out ofthe equation, yielding these simplified relationships.

7 Each ofthem assumes only one factor has been Change vs. Orifice Area ChangeQ2= Change vs. Pressure Drop ChangeQ2=h2Q1h1 This is the so-called square root law. Change vs. Specific Gravity ChangeQ2= of Changes in Operating Conditions on Pres-sure Drop Across an Orifice General Relationship:h2=Q22xA12xCd12xg2h1Q1A2Cd2 g1 Again, if any of the factors in this equation are unchangedfrom Condition 1 to Condtion 2, they can be dropped out toform simplified Drop Change vs. Flow Changeh2=Q22h1Q1 This is the square root law, stated another Drop Change vs. Orifice Area Changeh2= Drop Change vs. Specific Gravity Changeh2=g2h1g1 This relationship may not apply where specific gravity hasbeen changed by a change in gas temperature. See Page of Changes in Gas Temperature on Flow and Pressure Drop through an OrificeRaising a gas s temperature has two effects it increasesthe volume and decreases the specific gravity, both in propor-tion to the ratio of the absolute temperatures.

8 If we are con-cerned with changes in mass flows (scfh), these relationshipsmust be Change vs. Temperature ChangeQ2= Drop Change vs. Temperature Changeh2=TABS2h1 TABS1to maintain constant scfhCHAPTER 1 ORIFICES & FLOWSCOEFFICIENTS OF DISCHARGE FOR VARIOUS TYPES OF ORIFICESORIFICE FLOW FORMULAS((() ( ) ( )))Sharp EdgeCd = on angle. Seecurve at and Nozzles Discharging from PlenumAngle of Convergence in DegreesNOTE: The loss is least at 13 Coefficient of Discharge (Cd)0 2 4 6 8 10 12 14 16 18 20 22 in these tables are based on an orifice pressure dropof 1 and a coefficient of discharge (Cd) of determine flow through an orifice of a known the orifice diameter in the left-hand column of across to the column corresponding to the gas beingmeasured.

9 This is the uncorrected this flow by the coefficient of discharge of theorifice. (see page 4) this flow to the pressure drop actually measured,using the square root law (equation 2b, page 4).Example:What is the flow of natural gas through a 7/32"diameter sharp edge orifice at 6 pressure drop?From the table, uncorrected natural gas flow through a7/32" orifice is cfh at 1 a sharp edge orifice is (page ), so correctedflow is x = cfh at 1" pressure equation 2b, page 4,Q2=h2or Q2= Q1x h2Q1h1h1 Substituting the numbers for this case:Q2= x6 119 cfh1 determine the orifice size to handle a known flow at aspecified pressure drop, reverse the the known flow to a pressure drop of 1 ,using the square root the flow by the orifice the orifice table, locate the column for the gas underconsideration.

10 In this column, locate the flow closest tothe corrected value found in step to the left to find the corrected orifice : Size a gas jet for a mixer. Entrance to the jet ori-ficeconverges at a 15 included angle. Gas is propane. Requiredflow is 120 cfh at 30 pressure equation 2b, page 4,Q2=h2 ,or Q2= Q1x h2Q1h1h1 Substituting the numbers for this case:Q2= 120 x 1 = 22 cfh30 From page , Cd for a 15 convergent nozzle is , socorrected flow is22 = cfh in the propane column of the orificetable and then read to the left to find a #26 drill size CAPACITY TABLESLOW PRESSURE GASCAPACITY,CFH @ 1 DROPAND COEFFICIENT OF DISCHARGE OF ,CFH @ 1 DROPAND COEFFICIENT OF DISCHARGE OF ,CFH @ 1 DROPAND COEFFICIENT OF DISCHARGE OF ,CFH @ 1 DROPAND COEFFICIENT OF DISCHARGE OF tables list compressible flows of high pressure gasesthrough orifices and spuds.