SU1227318A1 - Composition for heating the head part of ingot - Google Patents

Description

The invention relates to metallurgy, in particular, to compositions of heat insulating mixtures used for insulating a metal mirror during its casting into molds.

The purpose of the invention is to increase the yield of good metal and the quality of the ingot surface by improving the heat insulating properties of the mixture.

For the preparation of the mixture, exfoliated vermiculite and hydro4i1opite fractions of 0-10 mm are used.

Hydroflogopite is a hydromica with a different degree of hydration, having a melting point of 1370-14 ° C and a bulk density after expansion of 100-250 kg / m.

Ingredients

Swollen vermiculite Clay ogneupornna Ore vermiculite Graphite Hydroflogopite

The prepared mixture is poured into a mold before pouring steel in a siphon at the rate of 1.6-2.0 kg per ton

metal. g

When siphon casting steel into the mold, backfilling floats up and insulates the surface of the metal mirror. The fine fraction of vermiculite melted The melting point of the mixture

The thickness of the layer of the mixture, mm at the beginning of casting

after casting

five

0

five

18

With an increase in the content of the hydroplogopite mixture of more than 85% by weight, the heat insulating capacity of the composition decreases. When the content of hydroplogopite in an amount of less than 60 wt.%, The melting temperature of the mixture decreases, which leads to a decrease in the heat-insulating layer of the mixture from 100 to 60 mm and, accordingly, to an increase in the bulk mass of the mixture and a decrease in its heat-insulating ability.

In tab. 1 shows the compositions of the proposed mixtures (2-4), as well as mixtures containing ingredients above and below the proposed limits (1 and 5), and known (6) composition.

Table 1

Content, us. %

l ..

6

15

thirty

40

50

55 5

15 25

85

70

60

50

B is a form of slag and isolates the metal mirror from oxidation. As the heating proceeds, the vermiculite and hydroplogopite expand and insulate the surface of the ingot until it solidifies.

In tab. Table 2 lists the properties and results of the use of the heat insulating mixtures listed in Table. one.

Table 2

1400 1390 1336 1328 1350

90 87

90 86

95 72

85

78

Indicators

Bulk weight, kg / m

at the beginning of casting228

after casting,. 230 Thermal conductivity, kcal / mph hail

before testing after testing Head trimming,%

Laminated ingots that do not require surface stripping,% 11.0

Ingots requiring rolling due to surface defects,% 13.8

allowing its use to increase the yield of metal at

From the table. 2 data implies that the proposed mixture (as compared to the known one) possesses an improved quality improvement by the insulated heat insulating properties of the surface of cast billets.

Continuation of table 2

The compositions of the mixtures (according to table. L)

LjZJZJ ZEIl

183 171164135540

182 175170201360

0.064 0.0610.0580.0500.110

0,067 0,0650,0580,0830,950

11.7 11.5 11.612.412.6

12.4 .12.6 12,511,811.7

7.5 7.0 7.211.112.2

allowing its use to increase the yield of metal at

simultaneous improvement of the surface quality of cast billets.

Claims (1)

MIXTURE FOR WARMING THE HEAD OF THE INGOT, including expanded vermiculite, characterized in that, in order to increase the yield of metal and surface quality of the ingots by improving the heat-insulating properties of the mixture, it additionally contains hydrophlogopite in the following ratio of ingredients, wt. 2: Expanded Vermiculite 15-40 Hydrophlogopite 60-85 th to m with □ o 1 12