OWTHERM Heat Transfer Fluid A - Dow eLibrary

1 AProduct Technical DataDOWTHERM AHeat Transfer FluidFor further information, The United States And Canada: 1-800-447-4369 FAX: 1-517-832-1465In Europe: +31 20691 6268 FAX: +31 20691 6418 In The Pacific: +886 2 715 3388 FAX: +886 2 717 4115In Other Global Areas: 1-517-832-1556 FAX: 1-517-832-1465 : No freedom from any patent owned by Seller or others is to be inferred. Because use conditions and applicable laws may differ from one locationto another and may change with time, Customer is responsible for determining whether products and the information in this document are appropriate forCustomer s use and for ensuring that Customer s workplace and disposal practices are in compliance with applicable laws and other governmentalenactments.

2 Seller assumes no obligation or liability for the information in this document. NO WARRANTIES ARE GIVEN; ALL IMPLIED WARRANTIES OFMERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY March 1997 NOTE: SYLTHERM heat Transfer fluids are manufactured by Dow Corning Corporation and distributed by The Dow Chemical in *Trademark of The Dow Chemical CompanyNA/LA/Pacific: Form No. 176-1337-397 AMSE urope: CH 153-039-E-397 DOWTHERM* AHeat Transfer FluidProduct Technical Data*3 CONTENTSDOWTHERM A heat Transfer Fluid , Introduction ..4 Fluid Selection CriteriaThermal Stability.

3 5 Radiation Stability .. 6 Corrosivity .. 6 Flammability .. 7 Liquid and Vapor Phase TechnologyAdvantages of Liquid Phase Heating .. 8 Advantages of Vapor Phase Heating .. 8 Comparison of Liquid vs. Vapor Mass Flow Rates .. 9 Liquid Phase Heating .. 10 Vapor Phase Heating .. 11 Health and Environmental ConsiderationsHealth Considerations .. 12 Inhalation .. 12 Ingestion .. 12 Eye Contact .. 12 Skin Contact .. 12 Environmental Considerations .. 13 Stability .. 13 Movement .. 13 Bioconcentration .. 13 Customer ServiceAnalysis .. 14 Fluid Credit Return Program .. 14 PropertiesPhysical Properties.

4 15 Liquid Saturation PropertiesEnglish Units .. 16SI Units .. 17 Vapor Saturation PropertiesEnglish Units .. 18SI Units .. 19 Expansion of Liquid .. 20 Liquid Properties .. 21 Water Saturation .. 22 Pressure Drop vs. EnthalpyEnglish Units .. 23SI Units .. 24 Liquid Film CoefficientEnglish Units .. 25SI Units .. 26 Engineering DataPressure Drop vs. Flow Rate of LiquidEnglish Units .. 27SI Units .. 28 Pressure Drop vs. Flow Rate for VaporsEnglish Units .. 29SI Units .. 3030 Figure 19 Pressure Drop vs. Flow Rate of DOWTHERM A Vapor Inside Schedule 40 Pipe (SI Units) , C Temperature Correction Multiplier Factor Drop, kPa/100 m of pipeFlow Rate, kg/sec150 mm100 mm75 mm50 mm38 mm25 mmVELOCITY (m/sec)102040604*Trademark of The Dow Chemical Company Trademark of Dow Corning CorporationDOWTHERM AHEAT Transfer FLUIDSVERSATILE, STABLE, ANDPREFERRED DOWTHERM AHEAT Transfer FLUIDDOWTHERM* A heat Transfer fluidis a eutectic mixture of two verystable organic compounds, biphenyl(C12H10) and diphenyl oxide (C12H10O).

5 These compounds have practicallythe same vapor pressures, so themixture can be handled as if it werea single compound. DOWTHERM Afluid may be used in systems employ-ing either liquid phase or vapor phaseheating. Its normal application rangeis 60 F to 750 F (15 C to 400 C),and its pressure range is fromatmospheric to psig ( bar).Unsurpassed ThermalStability and Efficiencywith Technical Backupand Support to MatchDOWTHERM A Fluid , which hasbeen employed in industrial heattransfer systems for over 60 years,is the preferred product for a widerange of indirect heat transferapplications.

6 It is stable, does notdecompose readily at high temper-atures, and can be used effectivelyin either liquid or vapor low viscosity throughout theentire operating range results inefficient heat Transfer ; start-up andpumping problems are Fluid is noncorrosive tocommon metals and equal importance, but often over-looked, is the support provided bythe Fluid manufacturer. Dow s assis-tance to industry is unequaled. Thisincludes technical backup in thedesign phase, during operation andafter shutdown, as needed. Moreover,free analytical testing is provided tomonitor Fluid it is time to change out yourDOWTHERM A heat Transfer Fluid ,Dow s Fluid Return Program allowsyou to return the old Fluid andreceive credit toward the purchaseof your new Fluid , the capability of the manu-facturer to supply quality productin a timely fashion must be consid-ered.

7 Dow s large manufacturingcapacity and strategically placedwarehouses make DOWTHERM Afluid available when and where youneed 18 Pressure Drop vs. Flow Rate of DOWTHERM A Vapor Inside Schedule 40 Pipe (English Units) Drop, psi/100 ft of pipeFlow Rate, 1000 lb/hrVELOCITY (ft/sec)4"6"3"2"11/2"1" , FTemperature Correction Multiplier Factor For Information About Our Full Line of learn more about the full line of Dow heat Transfer Fluids including DOWTHERM synthetic organic, SYLTHERM siliconeand DOWTHERM, DOWFROST*, and DOWCAL* glycol-basedfluids request our product line guide.

8 Call the number foryour area listed on the back of this SELECTIONCRITERIAFour important properties that helpdetermine the viability of a heattransfer Fluid in a particular applica-tion are stability, vapor pressure,freeze point, and viscosity. These arediscussed StabilityDOWTHERM A Fluid possessesunsurpassed thermal stability attemperatures of 750 F (400 C).The maximum recommended filmtemperature is 800 F (425 C).2. Vapor PressureDOWTHERM A Fluid may be usedin vapor phase heat Transfer appli-cations from 495 F (257 C) to750 F (400 C). It may be used inthe liquid phase from 60 F (15 C)to 750 F (400 C).

9 Its vapor pres-sure is psia at 400 F ( barat 200 C) and psia ( bar)at the maximum recommended Freeze PointDOWTHERM A Fluid has a freezingpoint of F (12 C) and can beused without steam tracing in instal-lations protected from the ViscosityThe viscosity of DOWTHERM Afluid is low and changes onlyslightly between the melting pointof the product and its top operatingtemperature. As a result, start-upproblems are StabilityThe thermal stability of a heattransfer Fluid is dependent not onlyon its chemical structure but also onthe design and operating temperatureprofile of the system in which it isused.

10 Maximum life for a Fluid canbe obtained by following soundengineering practices in the designof the heat Transfer system. Threekey areas of focus are: operating anddesigning the heater and/or energyrecovery unit, preventing chemicalcontamination, and eliminatingcontact of the Fluid with Design and OperationPoor design and/or misoperation ofthe fired heater can cause overheat-ing resulting in excessive thermaldegradation of the Fluid . Some pro-blem areas to be avoided include:1. Flame Operating the heater above itsrated Modifying the fuel-to-air mixingprocedure to reduce the flameheight and pattern.