A method of producing a spark plug comprises (a) a step of combining a metallic shell and an insulator; (b) a step of inserting a portion of the assembly on its forward end side into a pressure container; (c) a step of bringing an insulating member into contact with the outer circumferential surface of a base side portion of the insulator over the entire circumference thereof, and pressing the assembly so as to close the opening by the assembly; and (d) a step of pressurizing the interior of the pressure container and applying a predetermined voltage between the terminal electrode and the metallic shell.

A leakage monitoring system for geomembranes comprises a power supply unit having two supply electrodes made from a nonmetallic conductive material and respectively connected to a membrane top and a membrane bottom of a primary geomembrane; a plurality of monitoring sensor electrodes made from the nonmetallic conductive material, uniformly arranged below the primary geomembrane and used for acquiring potentials at corresponding positions below the primary geomembrane; a data acquisition unit used for acquiring potential data of each monitoring sensing electrode; and a control and analysis unit used for analyzing the potential data of each monitoring sensor electrode acquired by the data acquisition unit, determining an abnormal potential area below the primary geomembrane to determine a leakage position of the primary geomembrane and giving an alarm. The abnormal potential area below the geomembrane can be determined to determine the specific leakage position of the geomembrane and give the alarm.

A method of producing a spark plug comprises (a) a step of combining a metallic shell and an insulator; (b) a step of inserting a portion of the assembly on its forward end side into a pressure container; (c) a step of bringing an insulating member into contact with the outer circumferential surface of a base side portion of the insulator over the entire circumference thereof, and pressing the assembly so as to close the opening by the assembly; and (d) a step of pressurizing the interior of the pressure container and applying a predetermined voltage between the terminal electrode and the metallic shell.

An inspection apparatus for testing of objects synchronizes a spark test wheel having probe fingers with a transportation unit on which spaced objects to be spark tested are placed. The probe fingers are arranged conically when the transportation unit is a turret.

A corrosion prevention survey system for determining locations of faults along an underground structure includes a data collector to record location data and voltage data; a voltage reading system to secure to a leg of a user, the voltage reading system having a pole with a spike to be inserted into a ground surface, the spike being able to read a voltage current running through the ground; an attachment device to secure the pole to the leg of a user; and one or more wires to connect the pole to the data collector; the pole is a predetermined length not greater than 2 feet; the voltage data is transmitted from the pole to the data collector; and the location data and voltage data are used in analysis to determine directions of voltage gradients for further determination of location of faults along the underground structure.

A composite structure of a cargo body and a method of making the same are disclosed. The composite structure includes at least one electrical grid embedded within fiber-reinforced polymer (FRP) layers. The embedded electrical grid includes a plurality of conductive fibers and a plurality of insulating fibers integrated into a polymer matrix of the FRP layers. The embedded electrical grid may be used for power distribution, structural strengthening and stiffness, and/or puncture detection.

The present invention relates to damage detection systems for refractory linings for molten metal vessels, comprising an electrically conductive grid disposed underneath the surface of the refractory lining closest to a molten metal when in use, one or more electrically conductive electrodes disposed in contact with the molten metal when in use and an electrical power source, wherein the electrically conductive metallic grid and the one or more electrically conductive electrodes are electrically connected to each other, such as to form an open electrical circuit powered by the said electrical power source, and a detected closure of the said electrical circuit during normal use of the molten metal vessel indicates that the said refractory lining is damaged, or the presence of a molten metal during normal operation of the vessel closes the said electrical circuit in case the refractory lining is damaged. The present invention relates to a method for detecting damage in a refractory lining during use, and the use of a damage detection system according to the invention.

An assembly includes an electrical conductor disposed within an elongate mineral insulated conductive sheath. The electrical conductor is electrically grounded to the conductive sheath. The assembly also includes a test conductor disposed within and electrically isolated from the sheath to provide an indication of the insulation resistance of the assembly.

Arrangement and method for detecting damage to an inner coating of a container is provided. The arrangement has been devised which is influenced by damage to the inner coating and/or actuation of plant parts (shut-off valves) and/or by electrical changes in the current paths. This is accomplished such that the latter generates a reproducible signal excursion which can be assigned to the respective activity and therefore to the corresponding parts of the plant, such as a container. Thus, by means of the measuring arrangement, both slowly changing values, which arise as a function of process-induced slowly changing process parameters, such as temperature, concentration, conductivity, and other gradually occurring damage to an inner coating, and also short-term significant changes of values are detected, which are brought about e.g. by pumping operations or by connecting together plant parts, which influence the electrical properties of the system. The detected signal excursion is interpreted.

Provided is a method for inspecting a heat sink that enables an accurate inspection of an insulating film formed on a surface of heat sink fins. The method including a metallic housing that includes a plurality of cooling fins arranged side by side on an outer surface thereof, and an insulating film formed on a surface of the cooling fins and between the cooling fins. The method includes disposing, in an electrolyte solution, an inspection electrode including a plurality of electrode fins insertable between the cooling fins to face the housing with a predetermined distance therebetween in such a way that the cooling fins and the electrode fins are alternately arranged; and applying a voltage between the housing and the inspection electrode, which are arranged to face each other, and inspecting a formation state of the insulating film based on a measured value of a current.