How to treat the plane starting point of ventilation pipeline

The plan mainly includes the basement ventilation plan, air conditioning duct plan and air conditioning water pipe plan.

Duct plan mainly reflects the layout of ventilation, air conditioning, smoke control pipes or ducts. In the construction drawing, double lines are generally used to draw, and the size of air duct (circular air duct is marked with diameter, rectangular air duct is marked with width× height), the positioning size and elevation of main air duct, the positioning size and quantity of various equipment and tuyeres, the installation position of various components such as muffler, regulating valve and fire damper, and the size and quantity of tuyeres, silencers, regulating valves and fire dampers are all marked in the drawing. On the drawing, the air duct is generally thicker, while the equipment, tuyere and air valve fittings are thinner.