Water hammer in steam distribution lines usually occurs when first supplying the steam. The previously mentioned method of operating valves slowly may help if the water hammer is caused by high-speed condensate slamming into piping, etc., but will not be effective if the water hammer is caused by the sudden condensation of steam.

As condensate is directly related to either type, properly removing condensate will lead to the most effective solution. Steam traps must be correctly installed so that the condensate inside the steam distribution lines is rapidly and completely removed.

If water hammer still occurs when proper care is given to the number and location of steam traps installed, the problem is most likely being caused by incorrect sloping of the piping. If the piping is not sloped correctly, the condensate cannot flow into the trap as planned, which can lead to high levels of condensate in unexpected locations.

In long steam distribution lines, even a slight rise in piping can result in water hammer. When installing piping using a roofline or the ground as a reference, make sure to double-check the slope of the piping.

Steam piping slopes downwards: No water hammer

Steam piping slopes upwards: Water hammer occurs

Among other possible causes of water hammer may be the accumulation of condensate where branch lines dead end. This is only a portion of the reasons why water hammer occurs. In order to truly eliminate the problem, a survey of the entire piping system should be performed to pinpoint the exact causes and plan suitable countermeasures.

Branch Piping Methods that Cause and Prevent Water Hammer