5 SF6 Gas Handling Tips You Should Know

1. Always Check Gas Quality Before Beginning Any Gas Handling

By-products of SF₆are hazardous to human health and can damage gas handling equipment -if proper equipment pre-filters are not used. . Thus, checking SF₆ gas quality before performing any maintenance is critical. Your technicians should use an analyzer before any type of handling procedure, which can check SF₆ volume percentage, moisture concentration, and arc-byproducts - without emissions. During any quality control activities, make sure technicians are wearing the appropriate PPE and following all safety guidelines.

1. Always Check Gas Quality Before Beginning Any Gas Handling

By-products of SF₆are hazardous to human health and can damage gas handling equipment -if proper equipment pre-filters are not used. . Thus, checking SF₆ gas quality before performing any maintenance is critical. Your technicians should use an analyzer before any type of handling procedure, which can check SF₆ volume percentage, moisture concentration, and arc-byproducts - without emissions. During any quality control activities, make sure technicians are wearing the appropriate PPE and following all safety guidelines.

3. Recover to Blank-off Pressure

Recovery is the process of removing SF₆ gas from gas-insulated equipment (GIE). A recovery system  has onboard compressors to remove the SF₆ gas  while filtering  out moisture and other contaminants.

If any residual gas is left in GIE, you risk harmful emissions. When using recovery equipment, the goal is to reach blank-off pressure: the lowest level of vacuum. This ensures that you’ve captured as much residual gas as possible. Minimum blank-off pressure levels are:

• <5 mbar (3.75 torr) for less than 100 lbs. of SF₆ gas
• <1 mbar (0.75 torr) for greater than 100 lbs. of SF₆ gas

To figure out the mass of SF₆ gas, consult an SF₆ density curve. Dividing the tank volume by density will determine the mass in pounds. 

4. Utilize the Correct Size Recovery System

Another important consideration in SF₆ gas recovery is the type of equipment you use. A  Mini-Series service cart is convenient for small GIE. But if you try to use it with large volumes of SF₆ gas, you’ll put stress on the equipment and you’ll spend much more time on recovery. A larger system can complete gas recovery in just a few hours while reaching the desired blank-off pressure.

Factor in hose length, as well: a longer hose might be a better fit in a larger facility, but it increases recovery time. DILO’s guide can help you choose a recovery system that can accommodate the volume of gas you are working with.

5. Remember to Cap Connections

This is a simple step that is often overlooked. To keep moisture, dust, and other debris out of SF₆ gas equipment, you must cap the connections once maintenance work is complete. Most caps are made from plastic, aluminum, or stainless steel. Metal caps are usually best, as they have an O-ring that blocks moisture. Some caps come with a tether, which is a good option if you’re worried about misplacing a cap connection. DILO offers seminars to help you navigate capping connections.

Need More Information?

Well-trained technicians are the first line of defense against SF₆ emissions. When it comes to operating SF₆ gas handling equipment, even the smallest error can have costly and dangerous consequences. Knowing the proper protocols and safety procedures is key.

At DILO, we offer industrial gas equipment, as well as SF₆ gas handling services. With a zero-emissions philosophy at the heart of everything we do, DILO provides virtual and in-person training on SF₆ gas handling. We are proud to be an accredited provider through International Accreditors for Continuing Education and Training (IACET). IACET Continuing Education Credits (CEUs) are the industry standard for high-quality education and training.

With more than 50 years of experience in the industry, DILO provides comprehensive services for SF₆ and alternative gasses combined with best-in-class customer care. We are headquartered in Odessa, Florida, and serve clients around the world. For more SF₆ gas handling tips and training opportunities, check out DILO Academy today.