SU1252013A1 - Sand for making moulds - Google Patents

Description

125201

FIELD OF THE INVENTION The invention relates to a foundry, in particular to the manufacture of molds for raw materials.

The purpose of the invention is to improve the technological properties of the mixture by reducing shedding and gas creation, slowing shedding and compactibility.

The essence of the invention is as follows.

ten

Oil extracts contained in the mixture are obtained by phenol refining of distillate and residual oil fractions. Grade A has a kinematic viscosity at 100 ° C mm / s (cST D within 3-10, grade B - 10-15).

According to their physicochemical parameters, petroleum extracts must meet the requirements and standards specified in the technical specifications:

20 C, Not

Within 3-1G

Not less than 1,4900

Not less than 160 Not more than 0.015 Footprints

more than 980 25

thirty

35

40

The chemical composition of petroleum extracts according to specifications is as follows, wt.%:

Naphthenic hydrocarbons Resins

Aromatic Hydrocarbons

To obtain a mixture, three compositions were prepared, differing from one another in the content of an oil extract.

The content of quartz sand and bentonite is the same and corresponds to the 1GH average value of the ingredients (Table 1).

Table 1

Oil extracts

Own return of the mixture after its mechanical regeneration

0.01 0.05. 0.09

99.59 97.55 97.51

Samples were made from each mixture and tested on laboratory instruments. The compressive strength in the wet state was tested on the device of the PNR model, crumbling on the device of the PNR model, compactibility - on the device of the GF model, humidity by the method of drying to a constant weight.

The resulting properties are given in

Table 2. .P

Table 2

Gas permeability,%

Gas production, cm

Presence of burns

99

5.0

102

96

5.5 6.0

Otsut-Otsut-Otsutstvu-ostvuett emet

3

The yield of brilliant carbon of carbon-containing additives, petroleum extracts is about 3%.

Castings molded on automatic molding lines with the proposed mixture on medium-grained sands are, by surface finish, 3-A class according to GOST.

From the results given in Table 2, it can be seen that the proposed mixture has good indicators of crumbling, compactibility and gas creation.

The implementation of the invention allows to improve the technological properties

Editor A.Vorovich

Compiled by I. Kunitska

Tehred M. Khodaich Proofreader S. Shekmar

Order 4564/11 Circulation 757 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

134

mixtures reduce cast waste, oil extract consumption, bentonite consumption, transportation costs, mechanize and automate the processes of unloading, transportation and dosing, as well as improve sanitary and hygienic conditions.

In the composition of the sandy-clay mixture, molding clay can be used instead of bentonite to make casting molds.

Oil extracts as a carbon-containing additive can be used in known mixtures instead of coal, bonding CO, and others.

Claims (1)

MIXTURE FOR THE PRODUCTION OF CASTING FORMS, including quartz sand, bentonite, a carbon-containing additive and the own return of the mixture after mechanical regeneration, characterized in that, in order to improve the technological properties of the mixture by reducing crumbling and gas production, increasing compaction, it is a carbon-containing additive contains oil extracts obtained from phenolic purification of distillate and residual oil fractions, in the following ratio of ingredients, May. 7: Kvardepiy pepek 1.0-3.0 Bentonite 0.2-0.6 Oil extracts obtained from phenolic purification from distillate and residual oil fractions 0.01-0.09 Own return of the mixture after its mechanical regeneration SU .... 1252 ί