Compressed air systems of the past have incorporated many different materials for tubing. For example, it was not uncommon to use simple and inexpensive black iron pipe. In some cases, galvanized pipe was used to limit corrosion, and even copper and stainless steel have been employed. In addition, plastic has become more popular but many engineers, architects and contractors are now choosing round aluminum tubing for the job.
For many years, galvanized and black iron pipe were the main materials used for compressed air applications. In fact, today as many as 70 percent of new installations still use iron pipe because it is a cost effective choice. Plus, iron pipe is a material most contractors are familiar with and have experience installing. In other words, they may not want to invest in new installation equipment or learn new skills.
Iron pipe is very strong and can be used in high pressure systems. Plus, these materials are available at most suppliers. Yet, round aluminum tubing offers several advantages.
Total Costs
When you figure out the total costs you have to figure installation time. Even though you may save on materials with iron pipe, it can take a lot longer to install than round aluminum tubing. For example, each section of pipe has to be threaded before making a connection. This can be very time consuming and it takes specialized equipment. In fact, you may need to hire skilled workers for the job and this costs you more per hour.
Cutting pipe threads can create a mess because you need to use thread cutting oil and someone has to clean up afterwards. This is more time on the clock and adds to your installation costs.
If you are upgrading or making changes to a compressed air system, it takes more time when you have threaded iron pipe. In addition it is more difficult and time consuming because iron pipe is much heavier than round aluminum tubing.
Leaks
Because you have threaded connections and terminations, you have a good source for leaks. In fact, as many as ten percent of air leaks happen in iron pipe connections. Since aluminum tubing is not threaded, you eliminate this source for leaks.
Corrosion
Iron pipes will rust and corrode in time and this can be a problem. Condensation can form in air lines and this can cause a scale buildup in the pipes. However, since aluminum is non corrosive, it is not an issue. In addition, round aluminum tubing is a cost effective solution to copper and stainless steel. Plus, it is more durable than plastic pipe.
