API thread dimensions?

[Marecki_l]

I am new here and I'd like to ask for little help.
I am CNC programmer and going to make Interenal 6-5/8" API REG thread, I do have "Specification for Threading and
Gauging of Rotary Shouldered Thread Connections ANSI/API SPECIFICATION 7-2" and I did find almost all dimmensions excluding begining diameter of conus creating heads of thread profile. Only thing I have is diameter of entry taper, its lenght, and then thread profile dimensions. Box conus bore dianeter (entry conus) is tolerated 1.2 mm so it is quite big, I do not know if thread shape bottom is lying on "extenion" of that entry conus or it is somehow offset of it?
Can somebody help me to clarify that?
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1595323351/tips/IMAGE_3_juwzq3.bmp[/url]

 

[blacksmith37]

API 7 is drill pipe , nothing to do with API OCTG threads; 8 round and buttress ( reverse engineering has added some proprietary threads to the API category). You need API 5 Specification , likely 5CT for threads . Unless you want a rotary shouldered connections ; probably only used downhole.

 

[Marecki_l]

Thank you for quick response blacksmith37.
Well to be honest I am new in this matter and it is width field What I am doing is "box test connector" 6-5/8 API REG Low Torque thread. The item looks more less like this on attached picture, Spec 7-2 was most detailed document describing the thread I did find. Only thing missing was mentioned dimension. Of course I can turn rough taper way lower and turn the thread up to dimension using thread gauge for measuring. I only wanted to know how to count or find that missing diameter If I had to do symilar thing in the future.

 

[blacksmith37]

Diagram is a "rotary shouldered box connection" ; API 7. There connections are generally welded onto drill pipe. They are high strength , I don't remember the numbers, I was not on Com.7.