For each installation point, you need the right saddle if you do not have available port. The exact outer diameter is important to select the right saddle. Hot tap saddles are available from DN44 to DN600 in the temperature range up to 70degC. They can be used to create an installation point without welding.
The hot tap drill is the universal tool to install your insertion flow meter in any compressed air system. Using a hot tap saddle and a hot tap drill, you can create a new installation point without depressurizing your installation.