Pinhole detection system for glass wool paper by electric discharge

A pinhole detection system for glass wool paper has been developed based on electric discharge phenomenon. The main part of the system consists of two electrodes, i.e. anode and cathode, through which the glass wool paper passes. The line cathode consists of many needles with an equidistant separation of 6 mm. Three sets of line cathode, with needles at intervals of 6 mm, were shifted 2 mm from each other. A high resistance of 100 MΩ was used in the electric circuit to control the discharge current, i.e. damage to the paper. The detectable pinhole size using this system was between 0.1 and 1 mm. The detection rate was above 70%. The production rate of satisfactory goods was increased to approximately 33% as demonstrated in a manufacturing plant. [Copyright &y& Elsevier]