Rounded hole
<img src="https://eng-calculations.com/SVG/Hydraulic_engineering/Valves/Rounded hole.svg" alt="Rounded_hole" title="Rounded_hole">
https://eng-calculations.com/SVG/Hydraulic_engineering/Valves/Rounded hole.svg
<img src="https://eng-calculations.com/SVG/Hydraulic_engineering/Valves/Rounded hole.svg" alt="Rounded_hole" title="Rounded_hole">
https://eng-calculations.com/SVG/Hydraulic_engineering/Valves/Rounded hole.svg