Drawing Number: 21114
Revision: NR
OPERATION MANUAL FOR
ICP
HIGH PRESSURE SENSOR
Series 108B
2
Model 040A Reamer
Residue
Figure 2: Existing Recessed Ports Mount
During prolonged testing, should waveform distortion
occur, remove sensor and remove residue as shown.
It is important to note that, should the seal surface
require re-machining to clean up after prolonged use,
don't forge to deepen the 1/4" diameter hole by the
same amount. Otherwise, the sensor may bottom
when installed.
3.2
PREPARING NEW MOUNTING
PORTS
Refer to installation drawing provided in this manual
for instructions in mounting hole preparation. For
best results, do not deviate from the steps outlined in
this drawing.
Use good machining practice in preparation of the
mounting port, paying particular attention to the seal
surface (.323 diameter), and keeping it free from tool
chatter marks.
NOTE: It is important that this surface be perfectly
smooth and free from nicks or other discontinuities
which might cause leaks at high pressures.
3.3
RECESSED MOUNT
The recessed installation is shown in figure 3.
This type of mounting protects the sensor diaphragm
from the effects of high-flash temperatures and
particle impingement due to blast effects, thereby
prolonging sensor life.
The recommended range of passage diameters is .090
to .125.
The limitation in this type of installation lies in the
frequency-limiting effects of the passage due to its
length.
The passage behaves like an underdamped second
order
system,
the
resonant
frequency being
determined by the passage length. This can have a
limiting effect on pressure pulse rise time while
causing passage ringing in cases where the passage is
too long.
Figure 3
The following relationship determines this resonant
frequency (f
r
):
(Hz)
L
4
V
f
r
(EQ.1)
Where: f
r
= resonant frequency of passage (Hz)
V = Velocity of sound in air (ft/sec)
L = Length of column (ft)
.010
min.