Abstract: An improved apparatus for evaluating the continuity of the enamel lining of metallic containers. The apparatus has been developed for quality control inspection of containers and is designed to ensure that the entire interior surface of the container is evaluated by the test. The apparatus utilizes cooperating carbon electrodes of opposite polarity, an electrolyte solution, a grounded container, an enabling circuit and a meter to measure current flow through defects or discontinuities in the enamel lining. The carbon electrodes include a primary or measuring electrode, and a short secondary or liquid sensing electrode.Electrolyte solution is added until contact is established between the primary and the sensing electrodes thereby activating an enabling circuit which is used to control the meter display.

Abstract: An improved probe assembly for monitoring liquids is provided which includes an electrode housing having an internal receiving chamber, sealing packing means disposed in the chamber and a generally cylindrical electrode enclosed within a flexible, tube-like insulation sheath, which electrode and sheath extend through the receiving chamber and the sealing packing means. The electrode has at least one circumferentially-extending, radially-offset surface disposed opposite the sealing packing means defining an edge against which the sheath is compressed by the packing means so as to effect sealing engagement between the electrode and the sheath.