Investment casting glass pearl blasted
One of the production process for the investment castings in our foundry is sand blasting or shot blasting. The normally used medium used for sand blasting or shot blasting is sand or steel ball. The max. diameter for iron or steel ball we can make is bigger than 0.15mm. So, they work well for blasting the steel castings or iron castings, or castings with big size.
But for castings with high surface requirements or the wall thickness of castings are too thin to use the sand or steel ball as blasting medium, we will use glass pearl to instead of, which we call Glass Pearl Blasting or Glass Bead Blasting.
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By using glass pearl blasting, there will be no surface defects, such as the trails or dents. Thus, the surface of the investment castings will be much smooth.
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Usually used diameter of glass pearl we use is range from 0.05mm to 1.2mm. Below there 10 types of glass pearl we using.
| Grit Size(HK standard) | Grit Size(GB Standard) | Standard Size | Unit(Micrometer) |
| 0 | 320 | ≤325 | 53-0 |
| 1 | 280 | 299-325 | 74-44 |
| 2 | 220 | 140-270 | 105-53 |
| 3 | 180 | 140-200 | 105-74 |
| 4 | 150 | 100-200 | 150-74 |
| 5 | 120 | 100-140 | 150-105 |
| 6 | 100 | 70-140 | 210-105 |
| 7 | 80 | 60-100 | 250-105 |
| 8 | 60 | 40-60 | 420-250 |
| 9 | 30 | 15-14 | 1200-420 |
Application for the Glass pear blasting process are as follows:
1)Applied to the matte finishing for the stainless steel castings.
2)Deburring, rust clearing, stress relieving, surface polishing, wear resistance incleasing for the investment castings used for power instruments, medical equipments, or paper machinery building.
If you also have such surface treatment requirements for your castings, pls feel free to contact us!