DSP Corrosion-Erosion Monitoring 

 

The working principle of the ClampOn CEM is based on transmitting ultrasonic signals that propagate through the pipe-wall. The dispersive characteristics of a group of guided acoustic waves, called Lamb modes, are exploited to indicate a mean change in wall thickness relative to reference values acquired during the installation of the CEM system.

 

The permanently installed CEM system ensures that measurements are repeated frequently and in exactly the same manner, thereby eliminating the weaknesses of manual ultrasonic thickness gauging. Wall thickness trends are generated automatically and can be observed in real time.

 

The Corrosion-Erosion Monitor consists of a Head Unit and up to eight smaller transducers.

 

The Head Unit processes and controls the signals, communicating with the electromagnetic ultrasonic transducers which are fixed to the selected pipe section. The signal path follows the metal structure between the transceivers in operation, generating a matrix of measurements with thickness information. The number of Head Units and transducers to be used is decided by the client in consultation with ClampOn.

 

Testing has shown the ClampOn CEM to be both physically robust and capable of withstanding changes in pipe temperature. The system is capable of performing measurements on pipe diameters from 50 mm (2") and upwards and on material thicknesses ranging from 4 mm to 35 mm (0.157" to 1.378"). Changes in average wall thickness of as little as 1% can be measured in real time.

The signal path follows the metal structure between the transducers in operation, which in turn generates a matrix of all the measurements.

 

Our Corrosion Erosion Monitor will be interfaced using digital RS485 to a computer running our corrosion erosion software. The computer will then interface with the Control system using all available interfaces and protocols. It is optional how much data that will be sent across to the control system. As a minimum the average wall thickness will be used.

SAFE AREA EQUIPMENT
Mains power supply	12 - 48 VDC or 100-260 VAC 50-60 Hz
Power consumption	Max 2,5 W per sensor + computer rack module
INSTRINSICALLY SAFE (IS) APPROVAL
ATEX	II 2 (2) G Ex mb (ib) IIC T4, zone 1 II 2 (2) G Ex ib mb (ib) IIB T4, zone 1

ClampOn has since the beginning in 1994 grown to be the largest supplier of passive ultrasonic systems for sand/particle monitoring to the international oil and gas sector.

 

All products supplied by ClampOn, particle monitor, PIG detector, corrosion-erosion monitor, vibration monitor and leak monitor are based on the same, well proven technology platform. Both the topside and the subsea instruments incorporate Digital Signal Processing (DSP), complete digitalization eliminating analogue filters, circuits and amplifiers.

The ClampOn Ultrasonic Intelligent Sensor processes all data in the sensor itself (patented principle), thus enabling the instrument to discriminate between sand-generated and flow-generated noise. This is of importance to the user since changes in flow rates and the gas/oil ratio will not affect the performance of the system.

A good signal to noise (s/n) ratio is vital for quality measurements of this sort, and ClampOn’s sensors are the very best in this respect. With the new version, the external noise has been completely eliminated.
The sensors has memory capacity for storing up to 60 days of data, and can even be reprogrammed between being a sand monitor, a PIG detector or a leak monitor.

 

ClampOn Ultrasonic Intelligent Sensor

• Non-invasive
• Digital Signal Processing (DSP)
• Complete digitalisation
• No analogue filters, circuits or amplifiers
• Two-way communication
• Real-time measurement
• Easy to relocate
• Contains no moving parts
• Can be mounted in hostile environments
• Incorporates sensitive, intelligent, intrinsically safe sensors
• Can be upgraded by software download
• Can store up to 60 days of  measurement data within the sensor itself
• Self-testing capabilities
• Built-in temperature sensor and  accelerometer (optional)
• User-friendly software for Windows™ XP/Vista/2000-2008
• Versatile - one and the same sensor can perform particle detection, PIG detection, spectrum analysis and more, all available in the software package of your choice.