THE O R G A N I Z A T I O N OF C U R R E N T R E P A I R S

W I T H O U T B U R N I N G GAS A T THE M O U T H

V. E.

Translated from Metatlurg, No. 3, p. 11, March, 1962

OF B L A S T F U R N A C E S

When current repairs of the blast furnace are conducted, gas is burned at the mouth before beginning work. The gas is burned up, its concentration in the interbell area decreases, and the repair personnel can work with- out special apparatus for protection from gas. The interbell area becomes very hot during the process of burning the gas; the mechanica l equipment at the mouth is warped and goes out of order prematurely. The burning of the gas and the subsequent cooling of the mechanism takes 3-4 hours, i .e . , every current repair is protracted by this amount ,which greatly increases productivity losses. It has been established that the t ime required for the repairs is not shortened by working in special hose outfits without burning the gas. The hose outfits are cumbersome and inhibit the workers' movements.

In the blast-furnace mi l l of the Magnitogorsk Metal lurgical Plant, following the suggestion of V. A. Shastin, D. S. Gormakov, and I. Ya. Kalinichev, current repairs are being made without burning gas or constantly using the hose outfits: this is being done to shorten the delays related to the burning of gas and cooling of the equipment and also to allow work at the mouth without the hose outfits. Protection from the exudation of gas into the inter- be l l space is provided by filling the large be l l with a special sealing mixture of materials. The order of fill ing is the following:

1) With the smal l be l l closed and the distributor constantly turning, about 300 kg of asbestite is charged on to the smal l be l l and is then dropped onto the large bel l . 2) 500 kg of blast-furnace dust is charged onto the large be l l in the same manner. 3) The bIast-furnace dust and the asbestite mixture is then soaked with water, 4) Onto the be l l are then charged a skip (about 10 tons) of grade 11 ore and several skips of granulated slag; 5) One more skip of grade 11 ore is then added on top.

The filling takes about 30 minutes.

The large bel t thus sealed does not allow the passage of gas, and in the interbell space the gas concentration is usually not higher than allowed. The repair workers work without the hose outfits, the concentration of gases being constantly watched. If necessary, they put on the hose outfits.

As a result of the introduction of this procedure, a current repair is curtailed by about 3-4 hours; this amounts to a saving of about 4000 rubies per year.

The procedure can be recommended for introduction at other plants.

113