SandAlert control unit where the flow is displayed in real time. A simple and convenient solution
to the challenge of monitoring sand content within oil pipelines, even with a multi-phase flow. All
Pulsar SandAlert systems make use of an acoustic technique for determining changes in the
pipeline flow characteristics that indicate the presence of sand. The key to the success of the
Pulsar approach is simplicity in principle and rigorous sophistication in practice, using acoustic
analysis techniques developed over many years. A number of options are available for the
configuration of this control unit depending whether a fixed or portable installation is required
and the desired information flow. The output signal may be calibrated to a mass flow
measurement.
The unique acoustic sensor that forms the “ears” of the Pulsar system is an intrinsically
safe unit (ATEX EEx ia IIC T4) made from 316 stainless steel with environmental
protection to IP68. SandAlert is flexible for a wide variety of different applications,
and installation could not be simpler: the sand sensor is connected to the outside of
the pipeline with a stainless steel band, detecting changes in the acoustic signature
of flow within the pipe and converting that into a sand/solids impact rate. Because
the sensor monitors only a narrow frequency band, it is highly resistant to interference
from background noise, fluid or gas flow. Any pipe diameter is suitable and the
SandAlert may be positioned up to 1000m away using a standard instrument cable
connection.
SandAlert is simple to operate, and requires no calibration to the flow rate. As soon as the
sensor is clamped to the outside of the pipe it provides a measurement of flow rate. Because
the system is not affected by flow rate it is particularly suitable for multi-phase flows.
Pulsar has developed sophisticated software algorithms that analyse complex
acoustic waveforms automatically. Alarms are generated at user-defined levels of sand
production and a milliamp output proportional to sand flow levels is produced.
Communications capability via RS485 Modbus is included.
By calibrating the signal against known sand flow levels an a measurement of sand
flow within the pipeline can be derived.
