Dynasonics 902_903 Series Portable Doppler Ultrasonic Flow Meter - Manual (Page 16)

Rev. 10/08
- 14 - D902/3
To assure an acoustically conductive path between the
transducer face and the prepared piping surface, a
coupling compound is employed. Enclosed with the
D902/3 system is a tube of Dow Corning 111, silicone
grease. This couplant is satisfactory for temporarily
mounting the transducers to the pipe. If the installation is
long-term (more than a few days), Dynasonics
recommends utilizing a silicone-based RTV such as Dow
Corning RTV-732. If alternate couplants are utilized, the
grease chosen must be rated to not flow at the
temperature of the pipe.
1. Wrap the elastic strap (enclosed) around the pipe in the
area where the transducers are to be mounted. Mount
the strap snuggly, but leave the strap just loose enough
to allow the transducers to be placed underneath.
2. Spread an even layer of coupling compound,
approximately 1/8 inch (3 mm) thick, to the prepared
transducer mounting areas of the pipe. Utilize Dow 111
for temporary mounting or Dow 732 for permanent
mounting.
3. Spread an even layer of the coupling compound,
approximately 1/8 inch (3 mm) thick, to the flat face of
the two transducers.
4. Place each transducer under the strap with the flat face
positioned towards the pipe. The notch on the back of
the transducer will provide a mounting surface for the
strap. The transducer cables must be facing in the
same direction for proper operation. See Figure 7.
NOTE: Large pipes may require two people for this
procedure.
5. Tighten the strap tight enough to hold the transducers
in place, but not so tight that all of the couplant
squeezes out of the gap between the transducer face
and pipe. Ensure that the transducers are squarely
aligned on the pipe.
PART 2 - TRANSDUCER INSTALLATION
Figure 7
FLOW
DIRECTION