Skip to content Go to sitemap View accessibility statement
  • M-F 7a-5p EST
  • 800-222-2177
  • [email protected]
  • LinkedIn
ChemTec Equipment Company
  • About
    • Quality
    • Example Applications
    • Media
  • Product Catalog
    • Adjustable Flow Monitors, Sensors & Switches
    • Non-Adjustable Flow Monitors, Sensors & Switches
    • Flow Meters
    • Excess Flow Valves
    • Accessories
    • Request a Quote
    • Application Inquiry
    • Flow Monitors, Flow Meters, and Excess Flow Valves
  • Find A Distributor
  • Resources
    • News
    • Join Our Email List
    • Crash Course Videos
    • Terms & Conditions of Sale
  • Contact
  • About
    • Quality
    • Example Applications
    • Media
  • Product Catalog
    • Adjustable Flow Monitors, Sensors & Switches
    • Non-Adjustable Flow Monitors, Sensors & Switches
    • Flow Meters
    • Excess Flow Valves
    • Accessories
    • Request a Quote
    • Application Inquiry
    • Flow Monitors, Flow Meters, and Excess Flow Valves
  • Find A Distributor
  • Resources
    • News
    • Join Our Email List
    • Crash Course Videos
    • Terms & Conditions of Sale
  • Contact

Flow Switches & Excess Flow Valves for Cryogenics

Home » News » Flow Switches & Excess Flow Valves for Cryogenics
cryotherapy capsule
  • Originally published March 22, 2016
  • in ChemTec News & Updates

Cryogenics is the science of dealing with the production of and effects of very low temperatures. However, there’s some debate over how low ‘low temperature’ must be to qualify as cryogenic. Some say lower than -1000C. Others, such as NIST, put it at below -1500C. At these temperatures most gases become liquid, which gives them some interesting uses. Cryogenic temperatures are mostly produced through the Joule-Thomson effect, which takes advantage of the relationship between pressure, temperature, and volume.

Cryogenic applications

Cryogenic temperatures are needed in many fields. For example:

  • Superconductivity – cool a conducting coil enough and it’s electrical resistance disappears. This lets the coil build a very strong magnetic field. Superconducting magnets like these are used in MRI machines.
  • Cryotherapy – to remove abnormal skin cells by freezing.
  • Cryosurgery – to destroy abnormal cells within the body.
  • Cryogenic cutting tool treatment – to increase hardness and performance and extend tool life.
  • Recycling – to make soft, flexible plastics brittle so they can be ground and sorted.
  • Biological sample preservation.

Joule-Thomson cooling

At temperatures above absolute zero all atoms have some energy. Compress a gas and it becomes hot; a result of the energy of the gas atoms being condensed into a smaller volume. Take away this heat, then let the gas expand and it becomes cooler still as the atoms spread apart.

Many cooling systems achieve this increase in volume by releasing the gas through a valve or nozzle. Held under pressure, it expands rapidly, becoming much colder. This “Joule-Thomson” cooling is the basis of domestic refrigeration and air conditioning systems that recirculate the cooling gas.

Flow switches and Excess Flow Valves

In cryogenic cooling, as in any other system where a fluid is pumped through a closed loop, it’s important to incorporate monitors to detect abnormal operating conditions. Without them a pump might be starved of gas or a leak could go undetected.

ChemTec flow switches utilize a piston suspended in the fluid stream. A change in flow rate moves the piston, the position of which is sensed externally. When the piston moves outside of the limits a signal is sent that can trigger an alarm.

Excess Flow Valves (EFV’s) work in a similar way. A piston is held out of the flow magnetically. Should the flow increase suddenly, as if a pipe ruptures or a tube is disconnected, the sudden increase in flow triggers the release of the piston. This seals the pipe, stopping the flow.

Get advice on cryogenic applications

At low temperatures the behavior of many materials changes. Rubber in particular becomes very brittle. When selecting flow switches and EFV’s for cryogenic applications it’s important to discuss the specific details with technical specialists at ChemTec. With their deep product knowledge they can advise on appropriate temperature ranges and help in selecting the best switch, monitor or EFV for the job.

If you’re developing a cryogenic system, it’s not too late to reach out to ChemTec. Call us at (800) 222-2177 or email [email protected] to get the conversation started. 

  • Tagged as: chemtec, cryogenics, efvs, low flow

Recent Articles

A photo of a chemical processing plant with the Chemtec logo overlayed

Flow Solutions for Process Instrumentation and Sensors

January 22, 2025
A photo of rushing water in a narrow canal with the ChemTec logo and a dotted pattern overlaying the image.

The Future of Flow Control – Trends and Predictions

December 4, 2024
Photo of a hydrogen plant and the chemtec logo overlayed

Hydrogen Regulations and Applications of Excess Flow Valves

October 14, 2024

Quick Links

  • Online Product Catalog
  • Download Product Catalog (PDF)
  • Find A Distributor
  • News
  • Request a Quote
  • Application Inquiry
  • Join Our Email List
  • Online Product Catalog
  • Download Product Catalog (PDF)
  • Find A Distributor
  • News
  • Request a Quote
  • Application Inquiry
  • Join Our Email List
ChemTec Equipment Company

Monitoring Perfection Since 1968

Based in the USA
3077 S.W. 13th Drive
Deerfield Beach, FL 33442

Toll-Free: (800) 222-2177
Local/Int’l: +1 (954) 428-8259

Proud Supporter of Florida Trade

Florida Trade Logo - ChemTec is Proud Supporter of Florida Trade
As seen in: Industry News Alert. Hydraulics and Pneumatics. Process Cooling. The Morning Bell.
Copyright © 2025 ChemTec Equipment Company, Inc., All Rights Reserved. Web Marketing by Connect Agency.
  • Quality
  • Terms & Conditions of Sale
  • Website Privacy / Terms
  • Cookie Policy
  • Accessibility Statement
  • Sitemap
  • Quality
  • Terms & Conditions of Sale
  • Website Privacy / Terms
  • Cookie Policy
  • Accessibility Statement
  • Sitemap
ChemTec's Newest Excess Flow Switch Designed for Ultra-High Purity Applications. Inventory available for immediate delivery. Contact us for in-stock sizes and flow rates. Request more info about ChemTec's LPH UHP 250/375 Series and LPH UHP 8 Series. Two CAD images of the LPH UHP 250/375 and the LPH UHP 8.
By continuing to use our site, you acknowledge that you accept our Website's Privacy Policy and Terms of Use. We also use cookies to provide you with the best possible website experience. You can learn more about the cookies we use and how to manage them here.Okay