Grit, dirt or any foreign matter accumulated in the pipe can hinder efficient valve operation and seriously damage vital valve parts. Thoroughly clean pipe internally with air or steam.

• 砂砾，灰尘或任何在管道内累积的任何外在物质，都可能妨碍阀门的有效运行，并且严重损坏阀门的要害部件。要用空气或蒸汽全面彻底地清洗管道内部。