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Hull roughness measurement

  • Hull Roughness Analyser 
  • Computer is connected to the hand held carriage having a stylus measuring head. 
  • Stylus head is moved around the hull surface to measure and record the hull roughness profile. 
  • One traverse of the head at any point on the hull will collect information from 10 samples having length of 50 mm. 
  • For each 50 mm sample, the micro processor will assess the mean gradient through the peaks and valleys to give highest peak to lowest valley measurement for that sample. 
  • This measurement is known as Rt (50). 
  • Approx. 100 selected locations which must include bow, stern, mid ship, and boot topping area (area between load line and ballast water line). 
  • A number of traverses for stylus will give ‘n’ readings, hence the Mean Hull Roughness (M.H.R) at that station is average of Rt (50) 
  • There will be ‘m’ stations around the hull of the ship. Hence Average Hull Roughness (AHR) will be average of Mean Hull Roughnes

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