一、英制螺紋

（螺紋牙型角55度）Thread of British standard ( Thread pitch shape angle 55°)

BSW－－－－英國標準惠氏螺紋（粗牙）British Standard Whitworth Thread ( Coarse )

BSF－－－－英國標準惠氏螺紋（細牙）British Standard Whitworth Thread ( Fine )

G－－－－直管螺紋（外螺紋分A、B兩面級、絲錐分G、G－D）Straight pipe thread ( Outside )

thread in A\B: taps in G、G－D )

R－－－－錐管外螺紋（舊代號ZG;KG）Outside paper pipe thread ( Old thread code ZG,KG )

RC－－－－錐管內螺紋（舊代號ZG;KG）Inside taper pipe thread ( Old thread code ZG,KG )

二、美製螺紋

（螺紋牙型角60度）Thread of American standard ( Thread pitch shape angle 60°)

UNC－－－－統一制粗牙螺紋（代替NC）Unified coarse pitch thread ( Instead of NC )

UNF－－－－統一制細牙螺紋（代替NF）Unified fine pitch thread ( Instead of NF )

UNEF－－－－統一制超細牙螺紋Unified superfine pitch thread

UN－－－－－統一制不變螺距螺紋Unified thread

UNS－－－－統一制特殊螺紋Unified Special thread

NPT－－－－一般用途錐管螺紋（舊代號Z;K）Taper pipe thread for general purpose ( Old

thread code Z,K )

NPSC－－－－管接頭直管內螺紋Internal straight pipe thread for connection

NPSM－－－－裝置上自由配合，機械連線用直管螺紋Straight pipe thread for general purpose

NPTF－－－－幹密封錐管螺紋Dryseal taper pipe thread

NPSF－－－－幹密封燃油直管螺紋Dryseal straight pipe internal thread

NGT－－－－氣瓶用錐螺紋Special thread for gas cylinder

三、米制螺紋

Metric thread

ZM－－－－－米制錐管螺紋 Metric taper pipe thread

四、其它螺紋Other threads

SM－－－－縫紉機螺紋Thread for sewing machine

PZ－－－－氣瓶用錐螺紋Special thread for gas cylinder

5V1－20V1－氣門芯螺紋5V1－20V1－Tyre valve thread