Why must air present in steam lines and equipment be removed?

Air in steam lines and equipment primarily consists of oxygen and nitrogen. When steam comes into contact with these gases, especially oxygen, it can lead to corrosion in the form of pitting. Pitting is a localized form of corrosion that creates small holes or pits in the metal surfaces of pipes and equipment. This type of damage can weaken the structural integrity of the components and ultimately lead to premature failure.

By removing air from steam systems, the presence of oxygen—responsible for this destructive pitting—is significantly reduced, which helps to protect the integrity and longevity of the steam lines and equipment. This is why it is critical to maintain a steam system that is free from air and its associated gases.

While other aspects like efficiency, noise reduction, and thermal regulation are important in steam systems, the prevention of pitting due to oxygen presence is a primary concern that directly addresses the reliability and safety of the equipment.