Pressure and Temperature Corrections

Pressure & Temperature Corrections

These tables and examples are for correcting a flowmeter given the correct
flowrate ONLY if you are using a flowmeter outside of its designed parameter.
(ie, using a meter at anything other than STP - Standard Temperature and Pressure).

Pressure Effects

• Elevated pressures (above atmosphere)
allow for greater capacity for a given flowmeter

• To determine the actual flowrate (at the elevated
pressure), the following formula is used:

Pressure Effects

• All pressures are in absolute, not gauge

Temperature Effects

• Elevated temperatures (above standard
   atmospheric temperature) decrease maximum
   flowrate for a given flow body

• To determine the actual flowrate,
   the following formula is used:

Temperature Effects

• All temperatures are in absolute

Pressure Correction Example

• Our flowmeters are calibrated at a standard
   pressure of 14.696 PSIA (which is equivalent
   to 0 PSIG)

• If a customer is operating the meter at 20 PSIG,
   what will the effect be on the flow reading?

– The actual flowrate will be higher than
   that indicated by the flowmeter
      – How much higher will it be?

Temperature Correction Example

• Our flowmeters are calibrated at a standard
   temperature of 20 °C or 68 °F

• If a customer is using the meter at 30 °C, what
   will the effect be on the flow reading?

      – The actual flowrate will be lower than
     that indicated by the flowmeter
      – How much lower will it be?

Temperature Correction Example

Pressure & Temperature Corrections

Flowmeter Sizing

Chemical Compatibility Charts

Instruction Manuals

Gas Correlation Data

Glossary/FAQ

At Key Instruments, our success is built on recognizing that product manufacturers need more from their flow instrumentation suppliers than simply providing a standard product catalog. Manufacturers of medical equipment, industrial gas mixing and distribution systems, aquaculture control equipment, gas and liquid analyzers, water handling and treatment skids, and many others continue to partner with us due to our unique ability to drive costs out of the final product. When maintaining a world-class supply chain is critical, premier product manufacturers call Key.

Key Instruments manufactures precision machined acrylic flow meters, molded plastic flow meters, glass tube flow meters, flow control valves, and other products for a wide variety of markets such as medical, industrial, chemical, semiconductor, water, the laboratory, and more

Pressure & Temperature Corrections

Pressure Effects

Temperature Effects

Pressure Correction Example

Temperature Correction Example

Pressure & Temperature Corrections

Flowmeter Sizing

Chemical Compatibility Charts

Instruction Manuals

Gas Correlation Data

Glossary/FAQ