对于图中所示的喷咀(材料是3Cr13,调质后的硬度HB240～260)。我们采用锥体钻头和左螺旋角铰刀加工后,效率可提高两三倍。它的具体加工的过程为:1.用小头是φ8毫米,大头是φ13.8毫米,长度是28毫米的锥体钻头,采用n=380转/分的转速,钻至大头留余量0.3毫米左右;2.用小头是φ3毫米,大头是φ13.8毫米,长度为56毫米的锥体钻头,采用n=380转/分的转速,钻出最后一段孔, For the nozzle shown in the figure (material is 3Cr13, tempered hardness HB240 ~ 260). We use cone bit and left helix angle reamer, the efficiency can be increased two or three times. Its processing of the specific process: 1. With a small head is φ8 mm, the bulk is φ13.8 mm, the length is 28 mm cone drill, using n = 380 rev / min speed, drilling to the bulk of the remaining 0.3 Mm; 2 with a small head is φ3 mm, the bulk is φ13.8 mm, a length of 56 mm conical drill, using n = 380 rev / min speed, drilling the last section of the hole,