CAPACITY CALCULATIONS FOR STEAM LOADS

1 189 EngineeringSTEAM TRAP SIZING AND SELECTIONDrip Trap on STEAM Mains:Should be sized for 2X safety factor at full differential pressurePrimary choice for trap: 1/2 WD600L Thermodynamic3/4 WD600L ThermodynamicPlace trap every 200 ft. depending on type size, pressure,and piping Tracing:Typically a trap is placed approximately every 100 choice for trap: 1/2 WT2000 Thermostatic1/2 WT1000 ThermostaticBucket traps and thermodynamic traps are used on critical tracing applications where no condensate can Applications:2X safety factor based on differential pressureWhen used to drain a heat exchanger being supplied by a modulating control valve using less than 30 PSIG STEAM pressure, trap must handle full load at 1/2 PSI differential used to drain a heat exchanger being supplied by a modulating control valve using with STEAM pressuregreater than 30 PSIG use safety factor at fulI differential choice for trap: Float & ThermostaticCAPACITY CALCULATIONS FOR STEAM LOADSWhen BTU load is KnownCapacity of =BTUsteam required1000(lbs/hr)When Square Feet Equivalent CAPACITY of Direct Radiation (EDR) is Knownsteam required =Sq ft.

2 Of EDR(lbs/hr)4 When Heating Water with SteamCapacity of STEAM required=GPMx Temp Rise F(lbs/hr)2 When Heating Fuel Oil with SteamCapacity of STEAM required=GPMx Temp Rise F(lbs/hr)4 When Heating Air with STEAM CoilsCapacity of STEAM required=CFMx Temp Rise F(lbs/hr)900 HEATING AIR WITH STEAM PIPE COILSS team lbs/hr = A x U x (r)TLA = Area of heating surface in sq. = Heat transfer coefficient (2 for free convection)(r) T = STEAM Temperature Air Temperature in FL = Latent heat of STEAM BTU / lbENGINEERING428 Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax: McDaniel reserves theright to change the designsand/or materials of itsproducts without notice. 2006 Watson McDaniel CompanyWatson McDaniel reserves the right to change the designs and/or materials of its products without noticePre s s u (BTU/lb)Volume (ft3/lb)( F)SensibleLatentTotalCondSteam(Hg vac) (psig) of Saturated SteamPre s s u (BTU/lb)Volume (ft3/lb)(psig)( F) Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax.

3 191 EngineeringENGINEERING Warm Up LOADS in Pounds of STEAM per hour per 100 ft.

4 Of STEAM MainSteamPressure(psig)2 2-1/2 3 4 5 6 8 10 1214 16 18 20 24 Temperature at 70 F Based on Sch. 40 Pipe Up to 250 PSI. Sch. 80 Above 250 PSI. Sch. 120 5 & Larger Above 800 PSI0 FCorrectionFactor Running LOADS in Pounds of STEAM per hour per

5 100 ft. of STEAM MainSteamPressure(psig)2 2-1/2 3 4 5 6 8 10 1214 16 18 20 24 Temperature at 70 F Insulation 70% Efficient. 0 FCorrectionFactor Pipe Size428 Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax: PSIG Saturated SteamFor other pressures use correction factors0 ,000234510,000234510,000678234510,0002 STEAM Flow lbs/hrPressure Drop psi/100 factor3/4"1"1-1/4"1-1/2"2-1/2"2"3"4"5"6" 8"10"12"14"16"18"20"24"350 DROP IN SCHEDULE 40 PIPE192 Watson McDaniel reserves theright to change the designsand/or materials of itsproducts without notice.

6 2006 Watson McDaniel Company* Shaded portion is for sizing temperature pilot, solenoid, or temperature-solenoid combination valves only.+ Specify Low Pressure T PilotEngineeringSIZING STEAM PIPESS aturated STEAM lines should be sized for a STEAM velocity of 4800 to 7200 on pressure reducing stations should be sized for the same STEAM velocity onboth sides of the regulator. This usually results in having a regulator smaller than thepiping and having larger piping on the downstream side of the using STEAM Velocity Chart (opposite page):100 PSIG Inlet Pressure to control valve25 PSIG Outlet Pressure1000 lbs/hr flow rateDetermine pipe size requiredUpstream Piping: Enter Velocity Chart at A1000 line to B100 PSIG Inlet PressureFollow line vertically upwards to C1-1/2 Pipe DiameterSteam Velocity at Dshows 4800 Piping:Enter Velocity Chart at A1000 line to E25 PSIG Outlet PressureFollow line vertically upwards to F2-1/2 Pipe DiameterSteam Velocity at Gshows 5500 Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax.

7 193 EngineeringENGINEERING 1002003004005006008001,0002,0003,0004,00 05,0006,0008,00010,00020,00030,00040,000 50,000 Flash Vent Lines3,000 FPMH eating Systems4,000-6,000 FPMP rocess Steam8,000-12,000 FPM4,0005,0006,0008,00012,00020,00010,00 03,0002,0001,000 STEAM VELOCITY CHART(Schedule 40 Pipe)FCEBC apacity Pounds Per HourSteam Pressure PSIG(Saturated STEAM )0510255075100125150200250051025507 51001251502002501"11/4"11/2"2"21/2"3"4"5 "6"8"10"12"14"16"1/2"3/4"DGMultiply Chart Velocity by Factor below to getVelocity in Schedule80 PipePipe Size1/2"3/4" & 1"1-1/4" & 1-1/2"2" to 16" " Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax: CONDENSATE RETURN LINE,VENT LINE AND FLASH TANKV elocity in Condensate return Lines should be between 4000-6000 ft/min. In order to size the pipe we must knowCondensate load (lbs/hr)Inlet Pressure to STEAM Traps (PSIG)Return Line System PressureExample: using Condensate Line, Flash Tank, and Vent LineSizing Chart (opposite page):160 PSIG STEAM trap discharging to a 20 PSIG Flash load is 3000 lbs/hrFrom the Percent Flash STEAM Chartwe find that of the condensate will flash into STEAM .

8 Therefore .124 X 3000 = 372 of flash STEAM will be producedEnter Condensate Line Sizingchart at A372 lbs/hrMove horizontally to pointB20 PSIG Flash Tank PressureMove vertically upwards to point Dto determine a 5 Flash tank Tank Diameter is needed to keep velocities less than 600 to move vertically to point Eto determine that the VentLine on the Flash Tank should be 2 Diameter in order to keepvelocities less than 4000 to move vertically to point Cto determine that theCondensate Line Diameter should be 1-1/2 Diameter tomaintain line velocities between 4000 - 6000 McDaniel reserves theright to change the designsand/or materials of itsproducts without notice. 2006 Watson McDaniel CompanyEngineeringPERCENT (%) FLASH STEAMP roduced when condensate is discharged to atmosphere or into a flash tank controlled at various pressuresCondensateFlash Tank Pressure (PSIG)Pressure(PSIG) Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax.

9 EngineeringVelocity (ft/sec)20,000 CONDENSATE LINE, FLASH TANK, and VENT LINE SIZING(Schedule 40 Pipe)Flash STEAM Flow Rate (lb/hr)Pressure in Condensate Line or Flash Tank (psig)2"21/2"Multiply Chart Velocity by Factor below to get Velocity in Schedule 80 PipePipe Size 1/2" 3/4" & 1" 1-1/4" & 1-1/2" 2" & 3" 4" to 24" 26" to 30"Factor "1002003005008001,0002,0003,000805,0008, 00010,00030,00050,0006050403020101006650 3317106"5"4"8"10"12"14"16"18"20"24"26"28 "30"3/4"11/2"11/4"1"3"1/2"Velocity (ft/min)E60004000300020001000600D0510203 0406080100051020304060801000510203040608 0100 ACBC ondensate Return LineVent PipeFlash Tank Diameter195 ENGINEERING 428 Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax: McDaniel reserves theright to change the designsand/or materials of itsproducts without notice. 2006 Watson McDaniel CompanyEngineeringSingle Stage Pressure Reducing Station Using Pilot-Operated Regulating

10 ValveSeries Pressure Reducing Stations for Multi-stage Reduction of Pressure196428 Jones Boulevard Limerick Airport Business Center Pottstown PA 19464 Tel: 610-495-5131 Fax.