SU833358A1 - Lubrication for injection moulds - Google Patents

Description

(54) LUBRICANTS FOR PRESS-FORMS

one

The invention relates to foundry and can be used mainly in the manufacture of castings of non-ferrous metals and alloys by injection molding.

Known lubricants on the basis of oils and fats - technical petrolatum,% of fat, nigrol, fuel oil, ceresin and stearin D.

Closest to the proposed technical essence and the achieved result is a lubricant containing beeswax, paraffin, ® neural oil (nigrol or fuel oil) and a filler (aluminum powder) 121.

However, a well-known lubricant at high temperature has low anti-adhesive properties, does not protect the surface of the molds from sticking of the liquid metal, which reduces the cleanliness of the surface of the castings and contributes to the accelerated formation of the high-pressure mesh, which is one of the main reasons for the low durability of the molds. the metal is burned to form a large 1; the amount of smoke and gases, which leads to an increase in the porosity of the castings, the formation of sinks and a decrease in the purity of their surface. Besides

In addition, this lubricant is prone to component separation when. heating up. Aluminum powder is precipitated, and fuel oil, wax and paraffin are concentrated.

up.

The purpose of the invention is to eliminate the weld, increase the resistance of the molds, the quality of the surface of the castings and their uniform crystallization.

The goal is achieved

the fact that the lubricant, including paraffin, mineral oil and: a filling agent, is additionally used:; it is a soap powder, and silica is used as a filler in the following ratios of ingredients, wt.%: Mineral oil 10-20 Silicon powder 10-20 Soap powder 5-10

ParaffinEverything Else

Silicon powder introduced into the lubricant in the amount of 10.0–20 wt.% Eliminates the weld and prevents melting of the other components.

sudden changes in temperature and erosion of the mold, which ultimately increases the service life of the mold. In addition, since silicon has the ability to dissolve in many non-ferrous metals and alloys at high temperature with the formation of silumin, the outer layer of castings is more saturated silicon than the entire casting, which gives the outer layer greater ductility at high temperatures.

The main condition for ensuring good resistance of the alloy to the shrinkage stress is the presence in the alloy of a sufficiently large amount of eutectic (15-25%) or other crystallization component.

The presence of silicon powder in the lubricant composition ensures that this condition is met for the outer layer of the casting, without affecting the basic physicomechanical properties of the casting itself. Since the silicon content in the lubricant is quite large (10-20%), on the outer layer of the casting a structure of the zastectic alloy is observed over the entire surface of the casting, crystalline free silicon appears, which makes the casting insensitive to hot and cold cracks and promotes more uniform crystallization .

The presence of soap powder in the lubricant composition in the amount of 5.0-10% increases the temperature of the blender, prevents the lubricant from being separated into components when heated, promotes uniform distribution of the lubricant with a thin layer on the mold surface, which improves the surface of the castings, makes them shine . In addition, the soap itself also possesses the good characteristics necessary for

grease

The proposed lubricant is prepared as follows.

The soap is cut into small chips and placed in a heating chamber with a temperature of 11 ° -130 ° C. Soon, the outer surface of the soap dries out and Presence. The equipment There is Satisfaction. The cleanliness of the casting surface. The presence of mechanical connections. No No Uneven Uniformity of coating molds. The presence of cracks, gas shells.

becomes denser, and the moisture entering into its composition goes into steam and swells up the pieces of soap. Upon further cooling, the mass easily crumbles and a small powder of air-dry soap is obtained, which is sieved to clean the unwrapped pieces of soap and mix thoroughly with mineral oil heated to a homogeneous mass of the oil emulsion .. Then, it is ground in a ball mill and sieved through a 2000 sieve / cm poros yok silicon sieve. The powder obtained after sifting (fraction less than 0.005 mm) is used to prepare a suspension of silicon in an oil-emulsion emulsion. In the resulting suspension is poured a thin stream of molten paraffin. Stirring is continued until paraffin has set.

Before use, the lubricant is heated to. Lubrication of the mold can be applied by brush or spray.

The compositions and properties of the proposed lubricant are given in table. 1 and 2.

Table 1

Table No No SatisfyGood Good Unequal Uniform Uniform Dimensional None Same

The lubricant offered has good lubricating properties and is evenly distributed over the surface of the molds.

The implementation of the invention makes it possible to increase the durability of the molds, to improve the sanitary and hygienic working conditions and to obtain castings without cracks and gas shells with a high-quality, polluted surface.

Claims (2)

1. Kolobnev, I., F., and others. The Handbook of the caster M, Mechanical Engineering, 1974, p. 3464-365. 2. Authors certificate of the USSR. , 153546, cl. C 10 M 5/00, 1957.