SU1184602A1 - Method of preparing ceramic moulds before pouring them with metal - Google Patents

Abstract

THE METHOD OF PREPARATION OF CERAMIC CASTING FORMS BEFORE THE METAL FILLING, which involves calcining ceramic molds, cooling them to room temperature, shaping them with a hot filler with vibro-compaction, holding the molded ceramic forms in the filler before placing the molds, and then, in the case of 15–60 minutes, they should have applied to the caliper, put the pieces of the unit, if the unit has applied, they have, if they have applied, they have, if they have already applied to them. In order to improve the quality of castings by ensuring the packing density of the filler particles before metal pouring, after soaking the molds formed in the filler, the materials are repeated Additional filler vibration compaction before metal pouring.

Description

00

C35 O

to

The invention relates to foundry production and can be used in the preparation of ceramic casting molds before pouring metal in the production of castings according to melted models.

The purpose of the invention is to improve the quality of castings by ensuring the packing density of the filler particles prior to metal pouring.

The method is implemented in the following ways.

Ceramic shell molds made according to the known technology are preliminarily calcined at 900 ° C for 1 hour, cooled to room temperature, filled in flasks with a support filler (quartz nesing, mark 1К 0315А) heated to 650 ° С, compacted and maintained after seals for 30 minutes, then the filler is further compressed by vibration and the molds are poured with metal. The time of additional compaction by vibration depends on the technology of making the form, its

metal consumption and complexity of the structure and can vary within wide limits.

The additional vibration compaction of the filler, which is repeated before the metal is poured, eliminates the violation of the packing of sand particles caused by a decrease in the size of sand particles and an increase in the volume of flasks due to metal expansion during heating. The form is tightly held by the support filler and, if the formation of cracks occurs, the liquid metal does not extend beyond the cavity of the mold 1 1, therefore, conditions are excluded for blockages, scallops, etc., on castings. defects.

When conducting comparative tests of the proposed method of preparing ceramic casting molds before pouring metal and a known method (prototype), batches of "KSK-100 forage harvester fingers" apparatus are prepared.

Technological parameters of the methods are presented in table. 1, the test results in the table. 2

Gumming ceramic forms:

about temperature, C

time min

Backfill bearing pad (quartz sand):

temperature, C v bo uploplotnenie, with

Exposure after backfilling with support filler, min

Filler temperature

D. And after exposure, b

Additional vibration compaction, with

Table 1

900 60

900 60

650 7

650 7

thirty

thirty

80 480

Sand blockage, pcs

Ceramic blockage, pcs

Scallops, flows

Deformation of castings (non-trouble), pcs

Mechanical damage, Shrinkage looseness, pcs. Slag shells, pcs. Total rejects, pcs. /% Available castings Total castings

As can be seen from the results of comparative tests, the preparation of ceramic molds for casting according to the proposed method reduces the scrap castings for such

table 2

4 2

ten

2

one

one

11/6 189,200

to species, like sand blockage, scallops and nodules on castings, incorrigible deformation of castings, which more than halves the loss of castings.

Claims (1)

METHOD FOR PREPARING CERAMIC CASTING FORMS BEFORE FILLING WITH METAL, including calcining ceramic casting molds, cooling them to room temperature, molding with a hot filler with vibration sealing, holding the molded ceramic molds in the filler before casting for 15-60 minutes, characterized in that, in order to improve the quality of castings by ensuring the packing density of the filler particles before pouring the metal, after holding the molds molded in the filler, the second vibro-sealed is repeated before pouring its filler.