SU908970A2 - Contact device for plating tubular products - Google Patents

Description

(54) CONTACT DEVICE FOR GALVANIC TREATMENT OF PIPE PRODUCTS

I

The device relates to electroplating and can be used to carry electroplating, such as chromium.

Known contact device; Allowable for electroplating pipe products.

This device is made in the form of topod-supporting elements, contact pads, hingedly connected to the drive, and insulators, and the contact pads are made with holes, in which point-like spring-loaded contact elements are placed with the possibility of movement in a plane perpendicular to the tangent at the point contact with the surface of the workpiece.

In electroplating, the transfer of current from the product occurs through point contact elements, tightly pressed to the surface of the product with the help of. springs.

However, when operating the device and analyzing the work, uneven distribution was found in individual cases.

Kie current on point contact elements. The main reason for the uneven distribution of the current is different. pressure drop of the spring / spring under working deformation caused by tolerances on the wire diameter, winding conditions, etc., which is inevitable and is + 10%.

The voltage drop across the transitional resistance between the product and each contact element depends on the force pressing it to the product and can serve as a criterion for reliable contact.

The uneven distribution of the current leads to overheating of the point contact element and causes burnout, which affects the quality of the coating.

Claims (1)

In order to prevent the product from burning, at the site of contact, a certain amount of voltage drop is taken to be 2 0 6 mV depending on the current strength, wall thickness of the product and cooling conditions of the contact element. In the known device, to ensure reliable contact, a set of point contact elements is used, the number of which is chosen with a known margin due to the fact that the load on each of them is unevenly distributed. The purpose of the invention is to increase reliability by adjusting the force of the contact points to the product. This goal is achieved by the fact that the contacting device is equipped with a multipoint measuring and regulating unit, and the pressing mechanisms are installed on each contact element, the input of the block is connected to the product and each contact element, and the output of the block is pressed by a clamping mechanism. The drawing schematically shows a contacting device, a general view. The contacting device for galvanic processing of tubular products contains contact pads 1 with point contact elements 2 which are radically installed in them, each of which is pinched to the surface of the product 5 and the flexible wire 6 by means of a toothed rack 3 and a spring 4; to the current source bus. The flexible wire 7 from each contact element 2 and the wire 8 from contact with the product 5 are connected to the input of the measuring and regulating unit 9, which includes the voltage dropping device to the automatic switch of the measuring and regulating points. The output of the block 9 is connected with the executive bodies 10, each of which serves to press the corresponding contact element 2 to the product 5 through a reciprocating mechanism 11, made in the form of a gear 12, cooperating with the rack 3. The device operates as follows. The product 5 is installed in the terminal blocks 1. The point contact elements 2 are pressed tightly against the contact surface of the product 5. The gaps between the contact surface of the product 5 and the spherical heads of the contact elements 2 are selected by means of springs 4. Through flexible wires 6 connected to the power supply wiring, contact element 2 is supplied with current, and the cross section of each wire 6 is selected depending on the strength of the current. In electroplating of product 5, the voltage drop in the current transfer sections from point contact elements 2 to product 5 is measured and the voltage drop is compared to the nominal value by means of a measuring regulating unit 9. In case of deviation from the nominal value to the greater or lower side, the executive bodies 10 correspond to the current signal from the measuring and regulating unit 9 is processed by the imbalance that occurs through the mechanism of backward-translational movement 11, depending on the magnitude of the fall the voltages change the force of pressing the point contact elements 2 to the surface of the product 5, bringing the voltage drop to a certain value, for example, 3O-3S mV. The contacting device provides a high-quality coating by adjusting the current distribution to the point contact elements within specified limits by adjusting the pressing force of each point contact element to the surface of the product and reduces the number of point contact elements. Claims of Contacting Device for Galvanic Processing of Tube Products According to the Auth. NO 633940, which means that, in order to increase reliability by adjusting the pressing force of the contact elements to the product, it is equipped with a multipoint measuring and regulating unit, and the pressing mechanisms are installed on each contact element , with the input of the block connected to the product and each contact element, and the output of the block with the clamping mechanism.