Very often we take for granted the gas that is being supplied to our instruments, and that it will be of adequate purity and pressure to support our needs. There are a number of factors that can have a dramatic impact on the quality of the gas being delivered.
Below are a few suggestions on how to best design a gas delivery system.
- Place the source of gas as close as possible to the application/instrument. The purity of the gas will degrade while traveling through the gas delivery system.
- When making pipe connections use PTFE tape rather than paste. Paste may contain hydrocarbons which can contaminate the gas delivery system.
- Choose a gas supply that best meets your need. Consider storage space needed, proximity of your loading dock, and how often you will need to change cylinders or dewars.
- Select fittings appropriate for the tubing you are planning to use.
- Select pressure regulators appropriate for your application. If you are delivering high purity gas, then make sure that the diaphragm inside the regulator will not compromise purity.
- Consider pressure drops associated with tubing size, length, bends, fittings, and valves. Less complicated systems are better and help ensure that you maximize the pressure available from your supply.
- Place cylinders in a low traffic location. Always use a bracket and strap to reduce the potential for tipping.
- If you are using purifiers, make sure you maintain them at the recommended interval. Purifiers can help ensure the purity of gas delivered to your instrument, but if not maintained, they can introduce impurities.
- Consider storage needs for cylinders and dewars. For each cylinder or dewar in use there will likely be a minimum of one full cylinder and one empty cylinder that need to be stored.
- Think about safety and consult with your gas supplier or gas generator manufacturer about how to ensure the safety of you and your coworkers.
This post was contributed by Jennifer Fiorello, gas generation technology blog team member, Parker Hannifin Industrial Gas Filtration and Separation Division.