Strainers should be installed right to ensure it does removes the debris and does not become a source of wetness in steam.
As the marketplace becomes increasingly competitive, more emphasis has been placed on reducing plant downtime and maintenance. In steam and condensate systems, damage to plant is frequently caused by pipeline debris such as scale, rust, jointing compound, weld metal and other solids, which may find their way into the pipeline system. Strainers are devices which arrest these solids in flowing liquids or gases, and protect equipment from their harmful effects, thus reducing downtime and maintenance. A strainer should be fitted upstream of every steam trap, flowmeter and control valve.
Strainers can be classified into two main types according to their body configuration; namely the Y-type and the basket type. For steam, a Y-type strainer is the usual standard and is almost universally used.
Installing the strainer wrong can lead to it being a source of wet steam. As seen in the illustration below (fig 1) wrong installation leads to accumulation of condensate in the strainer basket and thus as steam flows it can carry this condensate. On steam lines, strainers should always be installed with their baskets on the side (fig 2). This ensures that wet steam does not erode the steam accessories and does not reduce the heat transfer rates.
Incorrect installation of strainer on steam line: (fig1)