前言 铝合金筒类铸件,一般外形结构较为简单,但加工要求较高。铸什的铸造方案多种多样。以往对于壁厚稍厚(>20毫米)的铝合企筒类铸件,大多采用加高、底注、明浇或阶梯式浇口加侧边冒口工艺。此方法对于高度<300毫米的铝合金简类铸件,一般尚能得到较为满意的效果。但对壁厚超过25～30毫米、并且高度>400毫米的铸件、则常因夹渣、气孔、夹 Preface Aluminum alloy tube casting, the general shape and structure is relatively simple, but the processing requirements are higher. Casting casting a variety of programs. In the past for the thicker wall thickness (> 20 mm) of aluminum alloy castings, most of the use of heightening, the end of the note, Ming pouring or step gate plus side riser process. This method for the height of <300 mm simple aluminum alloy casting, the general can still get more satisfactory results. But the wall thickness of more than 25 to 30 mm, and the height of> 400 mm castings, often due to slag, porosity, clamp