SU1564738A1 - Induction heater for continuous heat treatment of weld joint zone - Google Patents

Abstract

The invention relates to electrical engineering. The aim of the invention is to increase the stability of the mechanical characteristics of the weld metal and the heat-affected zone by increasing the uniformity of the tempering. The inductor allows the treatment consisting in heating the welded joint to the tempering temperature and holding it at this temperature while continuously moving it. For this, it has a heating section and several holding sections that keep the tempering temperature within the specified limits. Sections are formed by inducing conductors with a magnetic core from U-shaped sections of a certain length and installed with a certain gap. 2 Il.

Description

The invention relates to the heat treatment of metals, in particular, to devices for the continuous tempering of a weld metal.

The aim of the invention is to increase the stability of the mechanical characteristics of the weld metal and the heat-affected zone by increasing the uniformity of the tempering.

FIG. 1 shows the proposed inductor for continuous heat treatment of the weld seam area, longitudinal section4, FIG. 2 shows section A-A in FIG. one.

The inductor for continuous heat treatment of the weld zone of welded joints contains a water-cooled multi-turn coil 1, the turns of which are formed by inducing and return conductors, and the inductive conductors are covered by a magnetic conductor 2 made of U-shaped sections installed with a gap from each other. Below the inductor are welded connection 3 being moved relative to it.

The length of the outermost (first in the direction of movement of the welded joint) section of the magnetic circuit was 4–8 times greater

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above each of the following sections. The size of the gap between the sections changes according to the law of a decreasing arithmetic progression. The extreme section of the magnetic conductor is intended for local heating of the metal to a predetermined temperature, the subsequent sections installed with a regulated gap, to maintain a constant tempering temperature during the exposure time, which is determined by the speed of movement of the welded joint relative to the inductor and the length of the subsequent sections of the magnetic circuit.

The use of an inductor with the length of the extreme section of the magnetic circuit, less than a multiple of each of the subsequent sections, leads to overheating of the metal during aging. The use of an inductor with the length of the extreme section of the magnetic circuit, greater than 8 times the length of each of the subsequent sections, causes a decrease in temperature during tempering. The size of the gap between the sections of the magnetic circuit is changed according to the law of a decreasing arithmetic progression in order to compensate for heat loss as the heated metal moves to the output from the inductor.

The inductor works as follows.

Under the inductor, the beginning of the zone of the welded joint 3, which is to be heat treated is placed

ke. Include the power supply of the inductor and the actuator moving the welded joint. When a portion of the welded joint 3 enters the zone of action of the electromagnetic field created by the turns of the coil 1 and the extreme section of the pipe 2, the weld metal and the heat-affected zone begins to heat up. Have

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the output side of the extreme section of the metal temperature reaches the set. In the gap between the outermost and first of the subsequent sections, the metal is exposed to a lower voltage field than under the section of the current leads} covered by the magnetic circuit, and its temperature decreases slightly. Moving under the first of the subsequent sections of the magnetic circuit, the welded metal is again exposed to a more intense electromagnetic field and its temperature rises again and reaches the target or exceeds it by the value of the specified tolerance. During the subsequent movement of the welded joint in the zone of alternation of gaps and sections of the magnetic circuit, the temperature of the welded joint metal is maintained at approximately the same level.

Claims (1)

Invention Formula The inductor for continuous heat treatment of weld joints, containing a water-cooled coil, the turns of which are formed by inducing and return conductors, and the inducing conductors are covered by a magnetic conductor made of U-shaped sections installed with a gap from each other, because in order to increase the stability of the mechanical characteristics of the weld metal and heat-affected zone by increasing the uniformity of tempering, the length of one of the extreme sections of the magnetic circuit is 4 to 8 times longer than each and subsequent and specified clearances vary according to the law of diminishing zrifmeticheskoy progression. 2 Editor T. Parfenova Compiled by I. Salnikova Tehred M.MorgentalKorrektor M.Kucher va Order 1166 Circulation 681 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab., T. Ts / 5 ------------ Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 FIG. g Subscription