预钻 meaning in English
preboring
predrilling
subdrill
Examples
- Specification for side - pressure test of type ty predrill
Py型预钻式旁压试验规程 - Specification for sidepressure test of type ty predrill
Py型预钻式旁压试验规程 - Drilling method of pin hole : the pin hole shall be predrilled by supplier prior to hot dip galvanization
销钉孔的钻法：销钉孔应为供应商在热镀锌预钻好。 - Please use guide sleeve to protect the bit or tap and avoid the bit or tap slip during the work
为了保护钻轴寿命之长久及中心距离之准确度预钻之工作物须加用衬套并密著于工作物上。