Measuring P And L - GE AquaTrans AT868 User Manual

September 2004
Measuring P and L (cont.)
D-2
Use Figure D-2 below to properly measure the coupling length.
Typically, the transducer face is positioned just outside the inside
diameter (ID) of the pipe, or slightly retracted inside the coupling.
Figure D-2: Determining the Pipe Coupling Length
Use the following formula to determine the P dimension:
[ID + 2(WT)]/(cos MA) + 2(CL) - FD) = P Dimension.
For example, given the following:
•
inside diameter (ID) = 48"
•
wall thickness (WT) = 3/8"
•
installed coupling length (CL) = 2.0"
•
a transducer face depth (FD) = 1.75"
•
mounting angle (MA) - 45
The P dimension would be:
[48 + 2(3/8)]/(0.7071) + 2(2.0 - 1.75) = 69.4"
FD
o
MA 45
CL
o
Measuring P and L Dimensions