º£½ÇÊÓƵ

    Normally the diameter of the piping can be classified as outer diameter, inner diameter,and nominal diameter. The outer diameter of seamless piping is shown as D added with outer diameter dimension and wall thickness. For example, seamless piping of outer diameter 108 mm, wall thickness 5mm, shown as D108*5. Or adopting DN (Nominal diameter). Nominal diameter is specified for the design and maintenance,and is the name for pipes. Below is the conversion relation for pipes, threads and nominal diameter.