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    Fluid Properties Database

    Look up density, specific gravity, viscosity and vapour pressure for water, HCl, sulphuric acid, caustic soda and hypochlorite at your temperature and concentration — the properties every pump sizing and NPSH calculation needs.

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    Fluid & conditions

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    Awaiting Valid Duty Parameters

    Adjust the parameters on the left to compute live hydraulic values, ranges, and sizing verdicts.

    On-Site & Workshop Support

    Sizing on real liquid data

    Our engineers carry verified fluid data into every sizing and NPSH check — no water-curve shortcuts on chemical duties.

    Fluid properties for pump engineers

    1

    The four numbers that matter

    Density (or specific gravity) drives power — power scales with SG. Dynamic viscosity decides Reynolds number, friction and whether viscosity correction applies. Vapour pressure decides NPSHa and cavitation risk. All four change with concentration and temperature, which is why the database asks for both.

    Water at 30 °C: density 995.7 kg/m³, viscosity 0.80 cP, vapour pressure 0.042 bar. At 90 °C the vapour pressure jumps to 0.70 bar — nearly 7 m of head subtracted from NPSHa.

    2

    Reading the chemicals

    HCl 37 % at 25 °C runs about SG 1.18; NaOH 50 % about 1.52 with viscosity near 85 cP; 98 % sulphuric acid about SG 1.84. Hypochlorite sits near water density. Each row feeds directly into the sizing and NPSH calculators — enter the same chemical and temperature there for consistent results.

    Values are typical published figures, flagged for verification on critical duties. The platform reviews the data quarterly.

    3

    Why this matters on plant

    A pump selected on water properties for a 50 % caustic duty is undersized by half — power scales with SG. The same mistake on a hot HCl transfer invites cavitation, because vapour pressure was ignored. Teflow’s engineers use this data in every sizing and NPSH check; call +91 98251 62709 with your liquid and temperature for a duty confirmation.

    Frequently Asked Questions

    Technical & Operational FAQs

    Q1.Why do I need fluid properties for pump sizing?

    Power scales with specific gravity, friction and Reynolds number depend on viscosity, and NPSH available depends on vapour pressure. All three change with concentration and temperature — sizing from water properties alone gives wrong motors and cavitating pumps.

    Q2.What is the density of 37 % HCl?

    About 1180 kg/m³ at 25 °C — specific gravity 1.18. Viscosity is roughly 1.9 cP and vapour pressure near 0.05 bar. The database returns these at the concentration and temperature you enter.

    Q3.What is the vapour pressure of water at 60 °C?

    About 0.20 bar — roughly 2 m of head subtracted from NPSHa. At 90 °C it reaches 0.70 bar (7.1 m). This is why hot water and hot chemical transfers lose NPSH margin so quickly.

    Q4.How do I convert cP to cSt?

    Kinematic (cSt) = dynamic (cP) ÷ specific gravity. Water at 30 °C: 0.80 cP ÷ 0.996 = 0.80 cSt. For NaOH 50 %: about 85 cP ÷ 1.52 ≈ 56 cSt — well above the 40 cSt where HI 9.6.1 correction applies.

    Q5.Where does the data come from?

    Typical published values from standard chemical data references, reviewed quarterly and flagged as such. For critical design, verify with the supplier’s certificate of analysis and, where relevant, measured plant data.

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