Badger Meter Dynasonics DFX Series, User Manual

Page: 12 / 48

Transducer Installation
Page 12 August 2019 DPP-UM-00256-EN-03
Pipe Preparation
Before the transducer heads are mounted to the pipe surface, an area slightly larger than the flat surface of the transducer
face must be prepared If pipe insulation is present, it must be peeled back to expose the pipe surface Use a wire brush to
remove loose paint, rust, scale or dirt Paint, if bonded well to the pipe surface, does not need to be removed Any bumps
present on ductile iron pipe do not need to be removed Thoroughly dry the mounting surfaces so that the couplant grease
bonds to the surface
OTEE:
N
Small pits in the piping surface typically do not significantly impact ultrasonic transmission or signal reception
Couplant
Use a coupling compound to create an acoustically conductive path between the transducer and the prepared pipe surface
Clamp-on ultrasonic meters do not operate without coupling compound mounted between the pipe wall and the transducer
face Enclosed with the DFX system is a tube of coupling compound that is adequate for general purpose applications Use
a silicone-based valve grease or RTV (Room Temperature Vulcanizing) products or grease for Doppler installations as they
operate over a very wide temperature range In some installations, such as automotive, silicone is not permitted Alternate
petroleum-based products can be used, but verify that the grease is rated not to flow at the maximum surface temperature
anticipated on the pipe
In general, use the following couplants with these transducers:
Transducer Couplant
DT90, DT91, DT94, DT95 Dow 732 or Dow 111 (or equivalent)
DT92, DT93, DT96, DT97 Krytox® LVP
DP7 Not applicable
Table 1: Transducer couplants
DT9 Clamp-On Transducer Mounting
Clamp-on transducers should be mounted on the pipe 180° apart and facing each other on the pipe, with the cables on the
downstream side of the transducers If the pipe is horizontal, the preferred mounting orientation is 3 and 9 o’clock, with
12 o’clock being the top of the pipe See Figure 7 Orientation on vertical pipes does not matter
FLOW
Top View
of Pipe
Figure 7: Transducer Placement
Large pipe installations use stainless steel straps to secure the transducers to the outside of the pipe The DFX system is
shipped with four 36 in (900 mm) straps, which are suitable for pipes up to 39 in (1000 mm) diameter
1 Select the proper number of transducer straps to allow a complete strap to go around the circumference of the pipe If a
pipe is larger than 39 in (1000 mm), use a single strap/buckle arrangement to reduce the number of strap connections
The straps can be connected together to make a continuous length Small pipe installations use an integral clamping
mechanism built into the transducer
Pipe Size Straps Oequired
1…9 in (25…225 mm) 1
10…19 in (250…480 mm) 2
20…29 in (500…740 mm) 3
30…39 in (760…1000 mm) 4
Table 2: Straps required vs. pipe size