What are the arrows that need to mark water, steam and compressed air pipes for boilers?

Boiler feed water, steam and compressed air pipes need to be marked with flow direction arrows: steam and compressed air pipes.

Three elements of pipeline identification (pipeline color ring):

(1) Identify color, (2) Media name and (3) Flow direction.

All pipeline identification must indicate the identification color, medium name and flow direction, which are the basic three elements of pipeline identification. Some pipes must also be marked with pressure, flow rate, temperature, etc. Hazardous chemical pipelines need to use special hazardous chemical color rings, and fire pipelines must also indicate special fire protection.

The arrow of pipeline flow direction is the most direct and intuitive method to mark the flow direction of medium in pipeline. The flow direction arrow is composed of background color and arrow, which is pasted around the pipeline. The background color represents the dangerous nature of the medium in the pipeline. In GB723 1-2003, eight colors are specified for the colors of pipeline flow arrows. They are bright red, bright green, medium yellow, purple, light gray, brown, light blue and black. Among them, water that is harmless to human body is bright green, water that burns human body at high temperature is red, corrosive medium is purple, combustible liquid is brown, toxic and harmful gas is medium yellow, air is light gray, oxygen is light blue, and other liquids are black. The arrow of pipeline flow direction is further refined in various industries. For example, QSY 134-2005 Management Specification for Safety Signs of Petrochemical Pipelines is implemented in the oil industry, and Specification for Configuration of Safety Production Facilities in Power Generation Enterprises is implemented in the power industry.