Abstract: An apparatus for monitoring a cathodic protection system on a structure which is positioned in water such that a portion of the structure is beneath the surface of the water, such apparatus comprising: an insulating means positioned adjacent to the structure below the surface of the water; a metallic body positioned adjacent to the insulating means so that the body is electrically insulated from the structure; means for electrically connecting the body to the structure at a point above the surface of the water; and means for measuring the amount of current flowing through the electrical connecting means.

Abstract: An apparatus for monitoring a cathodic protection system on a structure which is positioned in water such that a portion of the structure is beneath the surface of the water, such apparatus comprising: an insulating means positioned adjacent to the structure below the surface of the water; a metallic body positioned adjacent to the insulating means so that the body is electrically insulated from the structure; means for electrically connecting the body to the structure at a point above the surface of the water; and means for measuring the amount of current flowing through the electrical connecting means.

Abstract: A method for determining the variations of the internal condition of a pipeline or tubing, by propelling a pig, which is sealed against the pipeline or tubing wall, through the pipeline by means of a constant flowing driving fluid comprising the steps of continuously measuring and recording the pressure of the driving fluid or the pressure differential across the pig during pigging of the pipeline or tubing and deriving from the recorded pressure signals a plurality of quantities representative for the pressure variations in selected successive intervals of the pipeline or tubing, each interval having a predetermined length, in such a way that the total length of the pipeline or tubing to be inspected is covered, and comparing the values of the quantities thus obtained with reference data of these quantities, and deriving from comparision information as to the internal diameter variations of the pipeline or tubing being inspected.

Abstract: The corrosion of a fluid-conveying metallic conduit is measured by electrically connecting relatively thick and thin walled sections of that conduit as the arms of an electrical resistance-measuring bridge.

Abstract: Multiple phase flow is detected and characterized in a fluid-containing conduit using a compressional wave acoustic transducer in the pulse-echo mode. The acoustic energy is transmitted in a transverse direction through the conduit and the returning echo is analyzed to determine if single or multiphase flow is present in the conduit.