55世纪一、钢结构(工程结构)件制孔优先采用钻孔，当证明某些材料质量、厚度和孔径(aperture)，冲孔后不会引起脆性时允许采用冲孔。钻孔是在钻床等机械上进行，可以钻任何厚度的钢结构构件（零件）。钻孔的优点是螺栓(组成:头部和螺杆组成)孔孔壁损伤较小，质量较好。

1、 Drilling is preferred for steel structure (engineering structure) parts. Punching is allowed when it is proved that the quality, thickness and aperture of some materials will not cause brittleness after punching. Drilling is carried out on the drilling machine and other machinery, which can drill steel structure components (parts) of any thickness. The advantage of drilling is that the hole wall damage of bolt (composition: head and screw) is small and the quality is good.

二、钢结构(工程结构)加工制造中，冲孔一般只用于冲制非圆孔及薄板(性质:宝石学术语)孔，冲孔的孔径(aperture)必须大于板厚，厚度在5㎜以下的所有普通钢结构件允许冲孔，次要结构厚度小于12㎜允许采用冲孔。在冲切孔上，不得随后施焊（槽形），除非证明材料在冲切后，仍保留有相当韧性，则可焊接施工。一般情况下在需要所冲的孔上再扩孔时，则冲孔必须比指定的直径小3㎜。

2、 In the processing and manufacturing of steel structure (engineering structure), punching is generally only used to punch non-circular holes and thin plate holes (property: Gem academic language). The aperture of punching must be greater than the thickness of the plate. Punching is allowed for all common steel structures with thickness less than 5 mm, and punching is allowed for secondary structure thickness less than 12 mm. No subsequent welding (groove) is allowed on the punching hole, unless it is proved that the material still retains considerable toughness after punching. In general, when the hole needs to be punched again, the punching must be 3 mm smaller than the specified diameter.

55世纪三、钢结构(工程结构)加工要求精度（度）较高时、板叠层数较多、同类孔较多时，可采用钻模制孔或预钻较小孔径(aperture)、在组装时扩孔的方法，当板叠小于5层时，预钻小孔的直径小于公称直径一级（3㎜），当板叠大于5层时，小于公称直径二级（6㎜）。

3、 When the machining accuracy of steel structure (engineering structure) is high, there are many layers of plates and many holes of the same kind, the method of drilling mould hole or pre drilling small hole diameter (aperture) and expanding hole during assembly can be adopted. When the plate stack is less than 5 layers, the diameter of the pre drilled hole is less than grade 1 (3 mm) of the nominal diameter, and when the stack is more than 5 layers, it is less than grade 2 (6 mm) of the nominal diameter.

四、钻孔时常用平钻头，钻不透孔用尖钻头。当板叠较厚，直径较大，或材料强度（strength)较高时，则应使用可以降低（reduce)切削力的群钻钻头，便于排屑和减少钻头的磨损(零部件失效的一种基本类型)。

4、 Flat drill bit is commonly used in drilling, and pointed bit is used for drilling hole. When the stack is thick, the diameter is large, or the material strength is high, a group drill bit which can reduce the cutting force should be used to facilitate chip removal and reduce the wear of the bit (a basic type of component failure).

55世纪五、长孔可用两端钻孔中间氧(Oxygen)割的办法加工，但孔的长度必须大于孔直径的2倍。

5、 The long hole can be processed by oxygen cutting at both ends of the hole, but the length of the hole must be more than 2 times of the diameter of the hole.

六、钢结构(工程结构)件钻孔时高强度（strength)螺栓孔应采用钻孔。

6、 When drilling steel structure (engineering structure) parts, high strength bolt hole should be drilled.