What causes water hammer in steam systems, which can lead to a line rupture?

Water hammer in steam systems is caused by the sudden condensation of steam into water, which leads to a rapid increase in pressure and can create shock waves. When steam comes into contact with cooler surfaces or water, it condenses rapidly, creating a high-velocity wave of liquid water that travels through the piping. This sudden change in pressure and the movement of this liquid can result in a strong impact against pipe walls or fittings, potentially leading to a rupture.

Mixing steam with water is particularly problematic because it creates a scenario where the energy of the steam moves into the water, generating momentum and resulting in hammering noises and severe stress on the piping system. This phenomenon can cause not only damage to the pipes themselves but also pose safety risks due to potential ruptures.

In contrast, while rapid cooling of steam may contribute to condensation, it is the interaction with water that specifically triggers the water hammer effect. Insufficient pressure and excessive steam temperatures can lead to other operational issues, but they do not directly cause the water hammer phenomenon.