GB/T 20330-2006

Active

Drill diameter for use prior to tapping screw threads

攻丝前钻孔用麻花钻直径

Standard Type

GBT

ICS

25.100.30

CCS

J41

Status

Active

Issue Date

2006-07-20

Implementation

2007-01-01

Centralized Committee

中国机械工业联合会

Issuing Authority

中国机械工业联合会

Application Summary AI generated

This standard specifies the appropriate diameters for twist drills used to create pilot holes before tapping screw threads. It is applied in manufacturing and machining contexts, particularly for metalworking operations where precise thread engagement is required, such as in automotive, aerospace, or general mechanical assembly. The standard ensures that drilled holes match the thread size and tolerance, preventing issues like thread stripping or improper fit.

Related Standards

GB/T 19323-2003 Coated abrasives--Plain discs with holes for dust extraction GB/T 4676-2003 Abrasive grains--Sampling and splitting GB/T 2492-2003 Bonded abrasive products--Permissible unbalances of grinding wheels as delivered--Testing GB/T 3045-2003 Abrasive grains--Chemical analysis of silicon carbide GB/T 19324-2003 Coated abrasives--Plain sheets with holes for dust extraction GB/T 6408-2003 Super abrasive--Cubic boron nitride GB/T 3464.2-2003 Long reduced shank taps GB/T 6087-2003 Key type three-jaw drill chucks

Transparency note: The application summary and key sentences on this page were automatically generated by AI from the standard's original text. This content has not been human-verified and should not be used for compliance or regulatory purposes. Always refer to the official standard document from the issuing authority.