Process Gases :: Helium

• Chemical symbol: He
• Second lightest elemental gas, after hydrogen
• Smallest of all molecules
• Lowest boiling point of any element (-452.1°F, -268.9°C, 4.2 K, 7.6 R)
• Seven times lighter than air
• Conducts sound three times faster than air
• Has five times air's thermal conductivity
• Does not become radioactive under irradiation

• Colorless
• Odorless
• Tasteless
• Non-toxic
• Inert
• Non-flammable
• Slightly soluble in water
• High thermal conductivity

• Helium is produced continually by the radioactive decay of uranium and other elements, gradually working its way into the atmosphere.
   
• Helium atoms are light enough to escape the Earth's gravitational field and into space.
   
• Commercial extraction from air is impractical because helium's concentration is only about five parts per billion.

• Commercially, helium is obtained from the small fraction of natural gas deposits that contain helium volumes of 0.3 percent or higher.
   
• Most of the world's helium comes from the Texas panhandle, Oklahoma, Kansas and the Rocky Mountains' eastern flank, other sources include the mid-east and Russia.
   
• These natural gas deposits contain more than 3,000 ppm of helium.

• At atmospheric pressure, helium becomes liquid at the lowest of all boiling points (-452°F, -269°C, 7.6 R).
   
• Helium remains liquid to absolute zero.
   
• The coldest known substance, helium is important for cryogenic research.
   
• At 3.9 R, liquid helium exhibits super fluidity or virtually zero viscosity (Helium II), defies gravity to flow up container walls and becomes nearly a perfect heat conductor.

Aerospace - Pressurizing, Inerting and Thermal Control.  Helium plays a unique and critical role in the pressurizing and purging of primary rocket propulsion systems. The propellant for these propulsion systems is a combination of liquid hydrogen and liquid oxygen.

Helium is vital for purging and pressurizing the liquid hydrogen fuel systems of rockets and spacecraft because of its:

• Low solubility
• Low boiling point (-452°F, -269°C)
• Inertness

Helium is also the only inert substance that remains a gas in such low temperature environments.

Aerostats and Balloons.  For decades, USW helium has been giving a lift to everything from simple party balloons to sophisticated lighter-than-air aircraft and aerostats carrying cargos ranging from weather forecasting instruments, television equipment and radar stations to communications relays.

Electronics. The world of electronics we often take for granted would not be possible without helium. That's because helium:

• Creates the controlled environments necessary for manufacturing semiconducting devices.
• Provides enhanced thermal conductivity.

Leak Detection.  In addition to creating controlled environments, helium's small molecules make it ideal for use with pressure and vacuum systems to detect and locate minute leaks that could impact the production and quality of semiconductors, and ensure that these systems are free of leaks.
 

USW offers the semiconductor industry several helium purity options, including STANDARD and ELECTRONICS grades.
 

• Tube trailers, which can be connected to a customer's systems
• Receivers, which can be installed on-site and filled as required
• Bulk liquid containers
• Cylinders