KR100347772B1 - A manufacturing method of Vitrified wheel for processing a Ball Bearing - Google Patents

Abstract

The present invention provides a longer grinding wheel life and higher efficiency and higher precision without causing damage to the workpieces (SUJ2, SUS, and plastic ball) by vitrified wheel for ball bearing processing. As,

Select granules made of fused alumina (Al ₂ O ₃ ) or silicon carbide (SiC) as a raw material in the asthma blender, add ₃ ~ 10wt% of liquid temporary binder and mix for 20 minutes Coating the binder on the substrate and mixing the Vitrified Bond (inorganic binder) with 50 wt% to 150 wt% of the mixture for 30 minutes, and the abrasive and vitreous coated with the temporary binder through the blender as described above. The compound obtained by blending the fed binder was put into a mold having a certain dimension (e.g. 700 (D) × 100 (T) × 420 (H)) and pressurized by a 1000TON press (about 150kg / cm 2), There is a point to be a step of forming the product and a step of drying the product molded by the mold for 7 days in a drying chamber at 120 ° C. and then sintering (firing) the product in a baking furnace at 1000 ° C. to 1500 ° C. for 5 to 10 hours. .

Description

A manufacturing method of Vitrified wheel for processing a Ball Bearing}

The present invention provides a longer grinding wheel life and higher efficiency and higher precision without causing damage to the workpieces (SUJ2, SUS, and plastic ball) by vitrified wheel for ball bearing processing. will be.

In the case of processing various soft and hard ball materials (SUJ2, SUS, Plastic ball, etc.) in recent years, it is necessary to increase the degree of material without the defect of the workpiece and to reduce the wear of the grinding wheel as little as possible.

Conventional grinding wheels have high porosity, which makes them difficult to grind due to excessively rapid wear, and it is more difficult to produce high precision products.

The present invention has been researched and developed in order to solve the above problems, the abrasive grain is a mineral binder (Vitrified) that has a suitable chemical composition range for the type and particle size selection and control of the abrasive grains and the binder By using Bond), it is characterized in that it is possible to manufacture high bonding (X-Z) grinding wheels close to inorganic balls, thereby enabling high efficiency (improved productivity) and high-precision grinding by increasing wear resistance without damaging the workpiece.

1 is a structural diagram of the present invention grinding grinding wheel

Figure 2 is a block diagram showing the process sequence of the present invention

Figure 3 is a graph showing the grinding wheel drying temperature and time of the present invention

1 is a structural diagram of a steel grinding bit grinding grinding wheel of the present invention, Figure 2 shows a manufacturing process diagram of a steel grinding bit grinding grinding wheel, abrasive (Abrasive) is used as in Table 1 to be described later As raw materials, Al ₂ O ₃ , SiC or Al ₂ O ₃ + SiC abrasive grains can be used, and coarse grains can be pulverized to a desired particle size in order to reduce cost and increase the filling rate when forming products. Temporary binders that can coat abrasive grains include dextrin, lignin, PVA, paraffin and industrial water.

Hereinafter, the manufacturing process of the present invention will be described based on FIG. 2 as an embodiment of the present invention.

Manufacture process

1) Blend

Select the abrasive grains made of fused alumina (Al ₂ O ₃ ) or silicon carbide (SiC) as a raw material into the asthma blender, add ₃ ~ 10wt% of liquid temporary binder, and add about 20 minutes. The amount of the binder is coated on the surface of the abrasive grains, and then, 50 wt to 150 wt% of the Vitrified Bond (inorganic binder) is added and mixed for 30 minutes. The chemical composition of the vitrified binder is shown in Table 2. As shown.

2) Pressurizing and forming

As described above, the mold obtained by mixing the abrasive coated with the temporary binder and the vitrified binder through the asthma mixer was manufactured to a certain dimension. [Mould (e.g., 700 (D) × 100 (T) × 420 ( H))] and pressurized and molded by 1000TON press (about 150㎏ / ㎠).

3) Sintered (fired)

The product molded by the mold by the above method is dried for 7 days (see Fig. 3) in a drying chamber at 120 ℃ and then sintered (fired) for 5 to 10 hours in a firing furnace at 1000 ℃ 1500 ℃ inorganic ball It will produce a high binding grinding wheel close to.

The present invention manufactured by the above method can be used in various abrasive grain types and particle size for steel ball grinding grinding wheel, which is shown in Table 1.

In addition, the binder used in the present invention is shown in Table 2 as its chemical component as vitrified.

As described above, when mixing, forming, and firing an inorganic binder bitifier in an abrasive grain made of molten alumina or silicon carbide, the single-component constituent of the inorganic binder (generally referred to as a mineral of a binder) is interposed between the molten alumina grains. Since it will penetrate into the pores of the role of the binder will be a grinding wheel of high bonding degree close to the inorganic pores as shown in FIG.

As described in detail above, the present invention may obtain the following effects by using abrasives as molten alumina or silicon carbide, and using bitifier as a binder thereto.

1) As the roundness of ball bearings is excellent, the life of grindstone can be extended because of excellent cutting and wear resistance.

2) The pore between the abrasive grains is a high binding sphere close to the inorganic pores by vitrite binder, and has excellent impact resistance.

3) Whetstone is composed of powder-like state, so high-precision polishing (finishing polishing) like bearing steel is possible.

4) High efficiency grinding is possible in the rough grinding process.

As a result of obtaining various advantages as described above, the high bonding grinding wheel of the present invention, which is close to an inorganic ball used in the steel ball processing industry, has improved productivity and high-precision polishing due to improved wear resistance without damaging the workpiece. The industrial value that can be processed is very good.

Claims (2)

Selected abrasive grains of molten alumina (Fused Alumina (Al ₂ O ₃ )) having a particle size of 180 to 8000 mesh as a raw material in the asthma blender, adding 3-10 wt% of liquid temporary binder, and blending for 20 minutes SiO ₂ 50wt ~ 80wt%, Al ₂ O ₃ 9-30wt%, Fe ₂ O ₃ 0-1wt%, CaO 1-8wt%, MgO 0-5wt%, K ₂ O 1-10wt% Na ₂ Adding 30 wt% to 150 wt% of a vitrified binder (inorganic binder) having a composition ratio of 0 to ₁₀ wt% of O0 and 0 to 3 wt% of TiO2, and mixing for 30 minutes; The compound obtained by blending in the above process is put into a mold having a certain dimension (e.g., 700 (D) × 100 (T) × 420 (H)) and pressurized and molded by a 1000TON press (150㎏ / ㎠). Process to let Steel ball (Ball) characterized in that the pressurized and molded product by the mold for drying for 7 days in a drying chamber of 120 ℃ and then sintered (baking) the product for 5 to 10 hours in a firing furnace of 1000 ℃ 1500 ℃ Bearing) A method for manufacturing a grinding wheel (Vitrified wheel) for machining. The method of claim 1, An abrasive grain is a method of manufacturing a grinding wheel (Vitrified wheel) for ball bearing processing, characterized in that the silicon carbide (SiC) having a particle size of 180 to 8000 mesh.