SPM condition monitoring of offshore platform


FPSO is moored on a single point SPM (steel structure with bearing on water and under water). FPSO revolves around a single point and rotates slowly with the tide. FPSO rotates around a single point through mooring chains such as mooning chains and yoke. The rotation speed is related to tide and sea state, and the rotation direction will change with the tide. The single point inner tower is connected with the seabed and does not rotate, while the outer tower rotates with the FPSO. Generally, there are four tides every day. Due to the action of tide, FPSO rotates around a single point. With the action of tide, a single point turns to the left for a period of time and turns to the right for a period of time. On average, the whole structure can not rotate several times a day. The structure diagram and field photos are shown in the figure above. Due to the large impact vibration of single point and the change of inclination angle, it is necessary to monitor the triaxial vibration and inclination angle of the whole single point online.

V530A miniature Tri-axial IEPE accelerometer,vibration sensor

  V530A miniature Tri-axial IEPE accelerometer,vibration sensor:
Model 530A is an IEPE triaxial accelerometer designed for industrial applications. The accelerometer uses shear piezo electronical  element  which  provides  a  wide  operating frequency range. The IEPE sensor combines outstanding crystals and low noise integral microelectronics to achieve 
very low sensitivity variation over the operating temperature range,  compared  to  other  sensing  element  designs.  The shear  element  technology  also  ensures  high  immunity  to base  strain  errors.  The  accelerometer  uses  a  welded titanium construction and a light weight 4 pins connector, or 
integral cable assembly for lower mass and wider frequency operation.  Excellent  frequency  response,  both  amplitude and phase, provide the user with a triaxial accelerometer ideally  suited  for  structural  and  component  testing,  drop tests and general laboratory vibration work. The miniature 
cube size of this accelerometer enables the test engineer or  technician  to  measure  the  accelerations  of  three orthogonal axes of vibration simultaneously on lightweight structures.  All  variations  provide  reliable  measurements and long-term stability. 
 

Feature / Application

• Tri-axial measurement

• 4 pins connector output

• Adhesive or stud mounting

• Hermetic sealed

• Annular shear mode

• Wide frequency response