Smooth surface is important
Make sure that the surface of the transducer face, as well as the plating and putty around the transducer is as even and smooth as possible. Obstructions on these surfaces will create problems with turbulent flow, and may cause noise.
Mounting screws or bolts must not be extruding from the transducer or the plating immediately around it. Obstructions on these surfaces will create problems with turbulent flow, and may cause noise.
The space around the threaded rods (or mounting bolts) must be filled with a a suitable filling compound (putty) and/or a locking ring. This is important to secure a firm installation and a level and smooth surface.
Note
Obstructions on these surfaces will create problems with turbulent flow, and may cause noise.