What prevents steam nozzles from becoming clogged with foreign material?

• A. Steam strainer
• B. Check valve
• C. Debris screen
• D. Nozzle guard

Answer: (A)

Steam strainer. A steam strainer is installed in the steam line before the nozzle and uses a screen to trap dirt, rust, scale, and other debris carried with the steam. By catching these solids, it prevents them from entering and clogging the nozzle orifices, and it’s designed so the collected material can be removed through blowdown or screen cleaning. The other devices don’t perform this filtration function in the piping leading to the nozzle: a check valve controls backflow, a debris screen is simply a filter but not the standard protective device in this placement, and a nozzle guard protects the nozzle from damage rather than filtering incoming steam.