SU1000153A1 - Secondary cooling device to unit for horisontal type iron continuous casting plant - Google Patents

Description

The invention relates to metallurgy and foundry, in particular to equipment for the production of pipes, machine-building blanks by continuous casting of ferrous and non-ferrous metals.

Apparatus for cooling a continuous ingot are known, comprising a pipe with sipe-shaped nozzles, for example, a device in which the transverse axes of symmetry of the slotted nozzles are arranged along one forming pipe, and the nozzles are made with a width increasing along the height of the pipe from bottom to top 1.

A device for secondary cooling of a continuous ingot is also known, comprising a collector with nozzles and a mesh diffuser, in which the mesh diffuser is semi-cylindrical in shape and installed from the nozzles at a distance of 2-10 diameters of the collector 23.

The closest to the proposed technical essence is a secondary cooling device for continuous casting of metal, containing walking beams, which are made in the form of a grating, in front of the cells of which are nozzles installed to supply water to the Gz.

A disadvantage of the known device is low reliability of operation. So, in case of emergency breakthroughs, the stationary installed cooling device for the liquid is liquid metal and cannot be damaged because it cannot be quickly removed from the workpiece, and the water necessarily falls on the liquid metal. When water is supplied under pressure to the nozzle, p spraying of jets dispersed by droplet-shaped nozzles occurs. Drops of the cooler fall on the surface of a hot ingot having a temperature of 950-1100s. Such hard cooling leads to uneven heat dissipation at different sites, film boiling occurs, leading to the appearance of cracks and microcracks, and this cooling is unavailable for alloyed steels and special steels according to the technology of casting. When casting iron, the process of uneven cooling proceeds in a similar way.

25 causing deterioration in the quality of workpieces due to defects in the form of microcracks on the surface and the appearance of chill in the form of cementite.

The purpose of the invention is to increase reliable

Claims (3)

30 ti work and improve the quality of blanks. The goal is achieved by the fact that the device is equipped with a rod on which sections are mounted, with sections made in the form of open rings with channels for air supply and the rod has the possibility of reciprocating movement. Figs, 1 shows the device cool | Denis, axonometric; Fig. 2 is a sectional side view. Sections 1 are rigidly connected by a frame 2 and fixed to a carrier rod 3. Each section is made in the form of an oval open semi-ring with a channel 4 for supplying air to a radially mounted non-uniformly along the CONTOUR half-ring (for example, four above and two below) nozzles 5 the semirings achieve greater cooling of the upper part of the surface of the workpiece, which contributes to the displacement of the liquid zone inside the workpiece to its center. This provides a more uniform heat dissipation over the ingot section, which favorably affects the uniformity of the structure and the strength of the casting. The sections are secured by a frame on the rod 6 with grooves 7 made therein, which allow them to move along the axis of the workpiece when reassembling. The rod is installed by two pairs of rollers 8 paired in height in the guides 9 of the support frame, made from a channel bar. Each half-ring has a size h in height not exceeding 2-2.5, and the bulkhead is the maximum diameter of the cast billet 10. When h 2 sDdd; The injector bar is close to the workpiece and the cone opens to the spray jet of the cooler on its surface tapers off without overlapping adjacent areas of the workpiece. At h 2, 5d (3n zagot. Nozzles do not ensure overlap of adjacent areas of the workpiece due to a decrease in the speed of the mist dispersible particles of the cooler. Thanks to the proposed design, sections and a given ratio of sizes of the spacer from the surface of the workpieces, effective cooling is achieved the surface of the workpiece, and the implementation of sections in the form of an open half ring allows instantaneous removal of sections from the workpiece using a rod moved on the coils in case of an emergency breakthrough of liquid iron. The device operates as follows: When the boom 3 is fed forward, section 1 advances the solution onto the workpiece 10 so that, in the working position, the oval half-rings are set along the axis of grabbing. They turn on the compressed air supply, which through the channel 4 in each half-ring goes to the formers 5 and It is ejected at high speed from their nozzles, whereby the cooling water rises from the collector through the supply pipes to each nozzle independently and sprays a stream of compressed air onto the surface of the workpiece. The process of intensive cooling proceeds, due to which they achieve an improvement in the quality of the workpiece due to the elimination of microcracks on the surface and chill. For example, with Continuous casting of the workpiece 3 D7220, 25-10 / 2 in the medium casting shop, using an experimental secondary cooling device, rejects are reduced by 15–20% through cracks, productivity increases by 8–12% compared with existing technology without secondary cooling. According to a preliminary calculation, the economic efficiency of the introduction of the device in two installations of UHP-2 due to the reduction of rejects by 15-20%, an increase in productivity of 1.1-1.2 times gives about 5 rubles. per 1 ton of continuous billet, which, with a production volume of 6 thousand tons of iron casting, saves about 30 thousand rubles. in year. Claims An apparatus for the secondary cooling of a continuous casting plant of a horizontal cast iron, comprising walking beams made in the form of sections with nozzles for supplying water, characterized in that, in order to increase reliability and improve the quality of the workpieces, it is equipped with a rod on which sections are mounted wherein the sections are made in the form of open rings with channels for air supply, and the rod has the possibility of reciprocating movement. Sources of information taken into account during the examination 1. USSR author's certificate No. 609592, cl. B 22 D 11/124, 1978. 2. USSR author's certificate number 692676, cl. In 22 D 11/124, 1980. 3. USSR author's certificate number 539675, cl. B 22 D 11/12, 1976.