another challenge with pipes and grooves

Hi all
once again I’ve stopped with a pipe I’m trying to model. Here is a printscreen from CAD. Any advice how to make it with a nice looking mesh will be appreciated, thanks.

A possible simple method

  • Add a Cylinder, press F6 and set the “Vertices” to 16 and “Cap Fill Type” to Nothing

  • Press CTRL+R to add a loop cut and with the mousewheel/numpadup/numpaddown add 3 cut

  • Select those vertices

  • In the Loop Tool addon panel press the “Circle” button, then press F6 and uncheck “Flatten” (so the circle still follow the cylinder shape), you can enable “Radius” and change the circle radius to what you need.
    Select then the center vertice of that circular part

  • Press G then press the letter of the axis that goes inside of the cylinder to constraint the move to that axis, move the vertice inside of the cylinder

  • Select the 4 faces that make this circle

  • Press I to inset a bit (in order to add a support edge around that circle border to sharpen it when we’ll use the subsurf), you can add another one if you want even sharper result

  • Add a Subdivision surface modifier

  • Add an Array modifier

cool, thanks a lot