What condition causes water hammer in steam lines?

Water hammer in steam lines primarily occurs due to the presence of condensate in the steam line. When steam travels through the piping system, it is supposed to remain in a vapor state. However, if condensate—water formed from the cooling and condensation of steam—accumulates in the pipe, it can create a blockage. As steam flows into this area, it can collide violently with the trapped condensate, generating a shockwave that results in the characteristic banging or hammering sound known as water hammer.

The presence of condensate can also compromise the efficiency of the steam system, as it can impede the flow of steam and create pressure fluctuations that might further exacerbate the issue. Proper drainage systems, including steam traps, are crucial to removing condensate from steam lines and preventing this condition.

In contrast, excessive pressure, inadequate insulation, and faulty steam traps can influence the overall functioning of the system but do not directly lead to the phenomenon of water hammer in the same way that the accumulation of condensate does.