Manufacturing of precision castings performed with lost wax process
JapaneseTechnologically-oriented・Design standard
Technologically-oriented
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[ Irrelevant design example ]
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The example of drastic change in the thickness ( T1 > 10T2 ) Its shape changes greatly and the accuracy of dimension gets worse.
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The example of extremely thin thickness Misrun happens often. (Although 1mm or more is desirable, around 0.5mm is locally possible)
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Case of W2 > W1 , H > 3W2 in the drawing Due to high defective fraction, W1 > W2 , H < 3W2 is better.
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Example of the tall tube with a bottom as shown in the drawing. Due to high defective fraction, it is better to make a hole in the bottom.
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設計基準
（イ）寸法公差 Linear Tolerance
| 寸法区分 Dimensions | 一般公差 Normal Tolerance |
|---|---|
| Up to 15mm | ±0.20mm |
| 15～25mm | ±0.25mm |
| 25～50mm | ±0.35mm |
| 50～75mm | ±0.50mm |
| 75～100mm | ±0.70mm |
| 100～125mm | ±0.90mm |
| 125～150mm | ±1.00mm |
| 150～175mm | ±1.10mm |
| 175～200mm | ±1.20mm |
| 200～225mm | ±1.30mm |
| 225～250mm | ±1.40mm |
| 250mm and Over | ±1.50mm |
（ロ）平面度公差 Flatness Tolerance
| 長さ Length | 一般公差 Normal Tolerance |
|---|---|
| Up to 50mm | 0.30mm |
| 50～100mm | 0.50mm |
| 100～200mm | 0.70mm |
| 200～300mm | 0.80mm |
| 300mm and Over | 1.00mm |
For investment castings, the dimension tolerance above are normally used.
Although, it is possible to narrow the dimension tolerance for certain
points by controlling the mold accuracy and manufacturing process.
In addition, it is possible to lower the cost improve the quality of your products by
combining castings with machining.
So please feel free to contact us.
（ハ）角度公差 Angular Tolerance
| 一般公差 Normal Tolerance |
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|---|---|
| α | ±1° |
| β | ±1° |
| γ | ±1.5° |
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| 表面粗さ Surface Roughness |
25S 以下 Under 25S |
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（ニ）Please inform a datum level for dimension measurement on a drawing of plural shapes.
バナースペース
Nidak Seimitsu, inc.
105-8 Ichinotsubo, Yunuki, Souma-City, Fukushima-Pref. Japan 979-2512