RU2416507C1 - Mass for production of abrasive wheel - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to grinding and may be used for production of abrasive tools, for example, grinding wheels. Proposed mass comprises the following components in the following ratio, in wt %: synthetic solid high-molecular resin - 85÷95, synthetic low-molecular resin with ultimate thermal stability of 125÷155° C and content of carboxyl groups of 4÷8 wt % - 15÷5, accelerating group - mercaptobenzothiazole -5÷10, filler - mix of zinc and magnesium oxides in equal fractions - 50÷70, and grinding material - 500÷700.

EFFECT: higher elasticity of grinding material.

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Description

The invention relates to the field of abrasive production, namely to the field of manufacture of an abrasive polishing tool.

Known mass for the manufacture of abrasive tools for surface finishing [1], containing a phenolic formaldehyde powder binder, phenolic formaldehyde liquid binder, vulcanizing and accelerating groups, fillers, grinding material.

The disadvantage of this mass is the insufficient high hardness of the resulting tool, the need for frequent editing of the tool.

The closest to the essence and the achieved effect to the proposed is the mass for the manufacture of abrasive tools [2], containing synthetic solid high molecular weight rubber 80-90 wt.h .; synthetic low molecular weight rubber with a heat resistance limit of 125-155 ° C and a content of carboxyl groups of 4-8 wt.% 10-20 wt.h .; vulcanizing and accelerating groups of 41.3-52.2 parts by weight, fillers 56-138 parts by weight; grinding material 900-1000 parts by weight; plasticizer-anti-aging agent 3-8 parts by weight As a vulcanizing group, the mass contains technical sulfur; as an accelerating group, it contains a mixture of captax and thiuram. An artificial technical cryolite, which is an inert component, is used as a filler. This mass in comparison with the above analog reduces the hardness of the resulting tool, but has insufficient elasticity, which does not allow to process complex profiles of parts.

The task of the invention is to increase the elasticity of the abrasive tool.

The problem is solved in that the mass for the manufacture of an abrasive tool containing synthetic solid high molecular weight rubber, synthetic low molecular weight with a temperature limit of 125-155 ° C and a content of carboxyl groups of 4-8 wt.%, An accelerator group, a filler, grinding material, and as the filler it contains a mixture of zinc oxide and magnesium oxide in equal parts, and as an accelerating group is captax, in the following ratio of components, parts by weight:

synthetic solid macromolecular 85 ÷ 95 rubber synthetic low molecular weight rubber with the limit of heat resistance 125-155 ° C and the content of carboxyl groups of 4-8 wt.% 15 ÷ 5 accelerator group 5 ÷ 10 filler 50 ÷ 70 grinding material 500 ÷ 700

The fact that magnesium and zinc metal oxides are used as a filler makes it possible to crosslink rubber molecules through carboxyl groups during heat treatment, while the accelerating group initiates the start of the interaction. Flexible strong bonds are formed between the rubber and the surface of the particulate metal oxides. The resulting structure eliminates the curing group in the form of sulfur, thereby increasing the elasticity of the tool. In addition, the resulting elastic mixture has better adhesion to the surface of the grinding material, which provides the necessary strength to the tool.

The decrease in the content of the claimed filler below 50 wt.h. and captax less than 5 parts by weight does not allow to achieve the required strength characteristics of the tool. The increase in the filler content of more than 70 parts by weight and captax more than 10 parts by weight leads to a decrease in ductility and to the difficulty of shaping the tool.

The inventive mixture is prepared as follows.

Prepare a mixture of synthetic solid high molecular weight and synthetic low molecular weight rubbers, add captax, filler: magnesium oxide and zinc oxide in equal parts and grinding material. The resulting mixture is thoroughly mixed for 10-15 minutes.

According to the proposed solution, a mass was obtained at the CJSC ROSSI in Chelyabinsk for the manufacture of polishing wheels. Cylindrical samples with a diameter of 16 mm and a thickness of 10 mm were formed from this mass, on which elastic recovery was measured on a plastometer according to GOST 415-75. Then, ring plates with an outer diameter of 150 mm, a thickness of 20 mm and an inner hole of 32 mm were formed from this mass, heat treatment and machining were carried out. The resulting tool polished the chip groove of the drill at a working speed of 18 m / s. The same groove was polished with a tool obtained from a mass made according to the closest analogue. The surface roughness was measured on an Abris-PM7 profilometer. Test data are summarized in table.

No. The filler content, parts by weight The content of captax, parts by weight The content of the vulcanizing group, wt.h. Elastic recovery, mm The surface roughness, Ra, microns one 45 four - 0.5 0.32 2 fifty 5 - 1,5 0.20 3 60 8 - 2.5 0.16 four 70 10 - 1,5 0.20 5 80 12 - 0.3 0.40 6 45 2 45 0.1 0.63

As tests have shown, the quality of the machined surface of the drill grooves in circles made of the inventive mass and having greater elasticity is higher and corresponds to roughness class 9, and the surface roughness treated with circles made from the mass corresponding to the closest analogue corresponds only to roughness class 7.

The proposed mass for the manufacture of abrasive tools will find application in the abrasive industry for the manufacture of polishing wheels.

Information sources

1. RF patent No. 2157750, Mass for the manufacture of abrasive tools, M.cl. B24D 3/22, dated 10.20.2000.

2. RF patent No. 2269408, Mass for the manufacture of abrasive tools, M.cl. B24D 3/22, 10/10/2005.

Claims (1)

A mass for the manufacture of an abrasive tool containing synthetic solid high molecular weight rubber, synthetic low molecular weight rubber with a heat resistance limit of 125 ÷ 155 ° C and a content of carboxyl groups of 4 ÷ 8 wt.%, Accelerator group, filler, grinding material, characterized in that it is used as a filler contains a mixture of zinc oxide and magnesium oxide in equal parts, and as an accelerating group - captax in the following ratio of components, parts by weight:
synthetic solid macromolecular rubber 85 ÷ 95 synthetic low molecular weight rubber with the limit of heat resistance 125 ÷ 155 ° C and the content of carboxyl groups 4 ÷ 8 wt.% 15 ÷ 5 accelerator group 5 ÷ 10 filler 50 ÷ 70 grinding material 500 ÷ 700