Loading patent…
AssigneeHarco Corporation
InventorsClark P. Weldon, Stephen L. Wolfson, Marvin L. Miller
Estimating the term…
In the present invention a method and apparatus for electrical surveys of offshore metal structures includes measuring the electrical potential difference between the structure and an electrolyte, such as sea water and/or the sea bottom, in which the structure is contained. Such measurements are made at roughly approximated recorded distance locations along the structure and the approximate distance information is corrected based on periodically taken accurate distance measurements. Provision is also made to correct data for line currents in the structure, and a method is disclosed for examining the effectiveness of an electrically insulating member connected in the structure. Moreover, an improved insulated wire having minimum insulation holidays and a method for making the same are disclosed.
A method of surveying a structure in an electrolyte, comprising moving a sensing means along the structure by means of a transporting means, sensing at locations along the structure the electrical potential difference between the structure and the electrolyte, measuring the approximate distances along the structure of a plurality of such locations relative to at least one of a reference position and a preceding such location to obtain information of the approximate position along the structure at which respective sensing steps are performed, making an accurate measurement of distance along the structure of at least one of such sensing means and such transporting means relative to at least one of a reference position and a preceding location, and correcting such approximate distances based on information from such accurate distance measurements.
Apparatus for surveying a structure in an electrolyte, comprising sensing means for sensing at locations along the structure the electrical potential difference between the structure and the electrolyte, measuring means for measuring the approximate distances along the structure of a plurality of such locations relative to at least one of a reference position and a preceding such location to obtain information of the approximate position along the structure at which potential difference sensing has occurred, accurate measuring means for making an accurate measurement of distance along the structure of at least one of said sensing means and said measuring means relative to at least one of a reference position and a preceding location, and correcting means for correcting such approximate distances based on information from such accurate distance measurements.
Dependencies are inferred from the claim text.