钻具螺纹API表示法、习惯表示法对照表
备注: 1. 1=PIN 公扣 0=BOX 母扣
2.LH—反扣,RH—正扣
3. NC—National Coarse Thread(国家标准粗牙螺纹/粗扣)
4. BTC—Buttress Thread Coupling
5. BCSG—Buttress Thread CSG
6. NPT—American Standard Taper Pipe Thread
7. NPS—American Standard Straight Pipe Thread