SU89731A1 - Test method for coating chemical equipment using electric current - Google Patents

Description

In order to detect defects in the enamel coating of chemical equipment, a so-called electrolytic method is used, which consists in that electrolyte is poured into the equipment under test and a current is applied to the metal body of the device under test. At the same time, in places of coating defects, an electrical circuit is closed. The disadvantage of this method is the duration of the operation and the inability to detect the finest defects of the coating.

The proposed method makes it possible to work much faster and to reveal the smallest defects of the enamel coating (hair trash, ions, bubbles, etc.). The difference with this method is in the use of high frequency and high voltage for one test. In places of defects, an arc of discharge occurs with a characteristic deposit that remains on the surface under investigation after the test.

The method is carried out as follows.

A coal electric voltage is supplied to an alternating voltage of 4000-8000 (1 with a frequency of 65000 Hz, which can be obtained, for example, from an alternating current network using a buzzer and a Tesla coil. An angle electrode is conducted along the enamel surface and between The enamel surface forms the initial stage of the corona discharge, which is accompanied by a violet glow and spark discharges. The voltage, even the maximum (8000 b), does not cause any damage to the enamel, since the breakdown voltage of the last 23600 It is usually between 0.7 and 1 mm. If there are defects such as pores, cracks, bubbles or an unacceptably thin layer of enamel in the enamel (on the order of 0.1-0.3 mm, in the places of defects, at the time of the electrode forms a transition from the corona and spark discharge to the area of the arc discharge, accompanied by sparks of white color, accurately indicating the location of the defect.

.in 89731-2

In addition to the white spark, arc discharges are usually accompanied by a strong crack. In places of defects, at the moment of arc discharges, a white bloom is formed, which remains after the test and accurately indicates the places of defects.

For the sake of safety, the body of the test article is grounded, rubber gloves and boots are put on and only after that the ebonite handle of the electrode is taken in hand and a high tension is applied.

The test of the proposed method enameled product capacity of 3. takes 15-20 minutes and gives a full guarantee of the proper verification of the quality of its coating.

Subject invention

The method of testing chemical equipment using electric current, characterized in that for detecting the smallest defects (hairline cracks, bubbles, etc.) and their visual observation, a high-frequency current and high voltage are used. connected to the carbon electrode, which is conducted on the surface to be tested, as a result of which arcs appear in places of defects and there remains a characteristic deposit on the surface, which allows to establish the places of defects.