SU991335A1 - Electrode for wire insulation continuous testing - Google Patents

Description

(54) ELECTRODE FOR CONTINUOUS WIRE INSULATION TEST

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The invention relates to electrical measuring technology and can be used to determine the electrical properties and the location of defects in the insulation of cable products.

A known electrode for continuous monitoring of the quality of the insulation, having a shaped holder and contacting elastic filler 1 fixed therein.

The drawback of the device is that when passing the bundle of the test wire, due to the continuous technology of making the wire, the elastic filler is destroyed due to the presence of a thickening of the wire at the bonding points; reaching three times the nominal size of the wire.

The closest in technical essence is a device for testing the electrical strength of a dry dielectric of an insulated electric cable, containing supporting insulators, a base, an outer pipe attached to it, inside which is coaxially electrically insulated, but an inner pipe is attached, and both have a cross section , in form similar to the cross section of the test wire. The outer tube has rods that are uniformly distributed over the entire inner surface of this tube, oriented radially inward of the tube and entering the inner tube hole with a gap of 8 & J. A voltage is applied between the tubes from a special generator, which ionizes the air space between the test wire and the inner tube, to which the test voltage 20 is applied from another high-voltage current source relative to the grounded conductor of the test wire 2j,

A disadvantage of this device is the low reliability of the testing RI, due to the large gap between the insulation of the test wire and the electrode, since in this case the distribution of the electric field between the ionized gas gap and the insulation of the test wire in the radial and tangential directions does not remain constant and not controllable.

The purpose of the invention is to increase the reliability of testing by limiting the gap between the electrode and the surface of the insulation of the test wire in the contact area, ensuring that the electrode can be adjusted to different sizes of the test wires.

The goal is achieved by the fact that in an electrode for continuous testing of wire insulation, containing supporting insulators, a base fixed on them, to which an outer tube with an inner tube installed therein, having both cross-sectional shapes, similar to the cross-sectional shape of the test wire, The inner tube is curved, for example, in a spiral, so that the gap in the inner tube corresponds to the nominal cross-section of the test wire. In addition, the inner tube is made flexible, for example, from a wire wound in a coil, and bolts are screwed into the outer tube in places evenly spaced along the length of the tube.

FIG. Figure 1 shows the proposed electrode for continuous testing of insulation of a round wire, a section; in fig. 2-6 are the positions of the inner tube and the shape of the lumen, the inside of it in the corresponding cross sections of the electrode.

The electrode contains a base 1, made of an angular profile, which is attached to the supporting insulators 2 by bolts 3 and has horizontal shelf. Elongated holes for fixing the front pipe k, the positions of which are set using adjusting bolts 5. In the outer pipe 4 there is internal bending the pipe 6 is bent in a spiral, the displacement of which in each bend is carried out by bolts 7 and inside which the test wire 8 is placed.

One output of the test voltage source (not shown) is through bolt 5, pipes 4 and 6 are connected to the insulation of the axially moving wire 8. The other output of the test voltage source is connected via a grounded structure to a grounded conductor of the test wire. Simultaneously with the start of movement of the test wire, it is necessary to apply a test voltage to the insulation of the test wire.

With this implementation of the electrode

some part of the inner surface. The curved pipe 6 in the form of a strip spirally enclosing the test wire 8, located in the inner pipe 6, will be extremely close to the surface of the insulation of the wire 8, forming the contact zone. At the same time, the cross section of this pipe 6 in any place will be sufficient for the passage of local thickenings, including the bundle of the test wire.

In the case of the contact version of the electrode, the accuracy of maintaining the test voltage on the insulation of the test wire does not depend on the electrode.

With a contactless design, the gap between the test wire and the electrode in the contact zone can be made so small that the loss of the ionization test voltage in it will not exceed the allowable value and significantly affect the distribution of the electric field in the insulation of the test wire.

This state of the electrode is provided in all cases and during the entire period of operation, if, in order to enable the electrode to be adjusted for different sizes of the test wires, the inner tube 6 is made flexible, for example, from a wire wound in a spiral, and into the outer tube C in places evenly spaced along the length of the pipe, screw in the bolts 7, which with their ends abut against the inner pipe 6 and bend it in the required direction. In such an electrode, it is possible to more accurately obtain the required dimensions of the lumen inside the inner tube for any size of the test wire. The proposed electrode for continuous testing of the insulation in a non-contact design allows testing with better quality and does not require a special generator, since the ionization at the contact points, due to the small gap between the elec; 1, the electrode and the insulation surface of the test wire, occurs under the test voltage does not require drying the wire before testing, as the wet surface of the wire only increases the contact area and improves working conditions by reducing the selected and ozone to acceptable standards. Claim 1, Electrode for continuous testing of wire insulation, containing supporting insulators, a base fixed to them, to which an outer tube with a core pipe installed in it is attached, having both cross-sectional shapes, similar to the cross-sectional shape of the test wire, differing in that, in order to increase the reliability of tests by limiting the gap between the electrode and the insulation surface of the test wire in the contact zone, the inner pipe is bent, for example, along Pirali so that the lumen of the inner tube corresponds to the nominal cross-section of the test leads. 2. The electrode of claim 1, in order to ensure that the electrode can be tuned to different sizes of the test wires, the inner pipe is made flexible, for example, from a wire wound in a coil, and into the outer pipe in places evenly spaced along the length of the pipe are bolted. Sources of information taken into account during the examination 1. USSR author's certificate No. 59923, cl. G01 R 31/16, 1977. 2. US Patent No. 3890566 ,. cl. 324-51, 1978 (prototype.

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Claims (2)

The claims 20 1. An electrode for continuous testing of wire insulation, containing support insulators, a base fixed to them, to which an outer pipe is attached, with an internal tube installed in it, having both cross-sectional shapes similar to 35 ^{6 the} shape of the cross section of the test wire. Characterized in that, in order to increase, reliability. test, by minimizing the gap between the electrode and the insulation surface of the test wire in the contact zone, the inner tube is bent, for example, in a spiral so that the lumen in the inner tube corresponds to the nominal cross section of the test wire. 2. The electrode according to π. 1, due to the fact that, in order to enable the electrode to be adjusted to different sizes of the tested wires, the inner tube is made flexible, for example, from a wire wound with a spiral, and into the outer tube in places evenly spaced along the length of the tube bolts are screwed.