Drawing Number: 21110
Revision: B
OPERATION MANUAL FOR
QUARTZ PRESSURE SENSOR
Series 118 & 119
1
1.0
INTRODUCTION
The 118 & 119 Series are acceleration-compensated,
high pressure sensors primarily developed to measure
ballistics chamber pressures for R & D and
production testing of ammunition. They may also be
used for explosive air blast and other high pressure
measurements in extreme shock environments where
ultra-fast, micro-second response is required. These
types of tests are usually accompanied by large
acceleration pulses, which can add considerable error
to output signals of un-compensated sensors.
The shoulder seal design features a one-piece
diaphragm machined integral with the housing for
ruggedness. A ceramic coating is applied to the
diaphragm to minimize flash temperature effects.
For applications where strain sensitivity from stress
within the mounting port is a concern, the 118B1X
and 119B1X utilize a floating clamp-nut design to
reduce the effects, where “X” denotes pressure range.
2.0
DESCRIPTION
The 118 & 119 Series contain an acceleration-
compensated piezo element. The quartz element
contains an integral seismic mass that counteracts the
acceleration effects of the end piece and diaphragm.
This compensation acts to extend the frequency
characteristics and enhance the transient response of
the sensor.
The machined diaphragm is made from maraging
steel, selected because of its high strength and
durability. The combination of the short, rigid
element and stiff diaphragm give these sensors a high
natural frequency and linearity.
3.0
INSTALLATION
With a 3/8-24 (M10x1.0 for metric mount) mounting
thread and flush diaphragm design, the 118 & 119
Series transducers mount directly in existing ports
machined for PCB Series 108 & 109.
Unlike conventional diaphragm type sensors, the 118
& 119 Series are pressure sensitive over the entire
frontal area. Extra care should be exercised to avoid
bottoming in the mounting hole when recess mounted
or when mounting into existing ports.
Install the sensor, using only one of the seals
provided, with the aid of a torque wrench to monitor
the mounting torque value. The recommended torque
range can be found on the installation drawing. Seals
should be replaced each time the sensor is re-
installed.
3.1
MOUNTING IN EXISTING
RECESSED PORTS
Before installing the sensor in previously used
mounting ports, clean out the residue from previous
tests. The port can be cleaned by hand reaming the ¼
inch diameter hole using a PCB Model 040A end
cutting reamer (040A07 for metric mount) guided by
PCB Model 041A pilot bushing (M041A for metric
mount).
Existing Recessed Ports
Pay particular attention to the sealing surface,
keeping it free from tool chatter marks, nicks and
other imperfections that could adversely affect the
seal. If the sealing surface requires re-machining
after prolonged use, refer to the installation drawing
to ensure that the ¼ inch hole is deepened to avoid
bottoming of the sensor when re-installed.
If waveform distortion occurs during prolonged
testing, remove the sensor and clean the residue as
illustrated above.
5/16 HEX
10-32 COAXIAL
CONNECTOR
3/8-24 THREAD
CERAMIC COATING
QUARTZ ELEMENT
MODEL 040A
REAMER
MODEL 041A
PILOT BUSHING
