Thread fit issues
Thread Content
Should a 60-degree tapered pipe thread be mated with a cylindrical pipe thread or again with a tapered pipe thread? GB/T12716 covers only external tapered threads and internal cylindrical threads – are these the two types of fits? How are tapered threads and straight threads combined? If not, then is it a tapered internal thread that matches the tapered external thread? Where can I find the relevant standards?
As stated in GB/T12716: Internal threads come in two types – tapered internal threads and cylindrical internal threads – while external threads exist only in the form of tapered external threads. Internal and external threads can form two types of sealing fits: a conical internal thread and a conical external thread together create a \"cone/cone\" fit, while a cylindrical internal thread and a conical external thread create a \"cylinder/cone\" fit.