Description
Popular Sizes
The thread dimensions shown in the following chart are those that may be used to determine a thread type in the field. For specific details of the threads, please contact Mills Machine Co.
Popular Sizes
The thread dimensions shown in the following chart are those that may be used to determine a thread type in the field. For specific details of the threads, please contact Mills Machine Co.
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 2 3/8″ Reg. | 3 1/8″ | 3″ | 1″ | 2.625″ | 3 1/4″ | 1 3/4″ | 3″ | 5 | TAPER | |
| 2 7/8″ Reg. | 3 3/4″ | 3 1/2″ | 1 1/4″ | 2.990″ | 3 3/4″ | 2″ | 3″ | 5 | TAPER | |
| 3 1/2″ Reg. | 4 1/4″ | 4 1/2″ | 3 3/4″ | 1 1/2″ | 3.490″ | 4″ | 2 7/16″ | 3″ | 5 | TAPER |
| 4 1/2″ Reg. | 5 1/2″ | 4 1/4″ | 2 1/4″ | 4.600″ | 4 1/2″ | 3 1/4″ | 3″ | 5 | TAPER | |
| 5 1/2″ Reg. | 6 3/4″ | 4 3/4″ | 2 3/4″ | 5.515″ | 5″ | 3 3/8″ | 3″ | 4 | TAPER | |
| 6 5/8″ Reg. | 7 3/4″ | 8″ | 5″ | 3 1/2″ | 5.975″ | 5 1/4″ | 4 3/4″ | 2″ | 4 | TAPER |
| 7 5/8″ Reg. | 8 7/8″ | 9″ | 5 1/4″ | 3 1/2″ | 6.975″ | 5 1/2″ | 5 1/4″ | 3″ | 4 | TAPER |
| 8 5/8″ Reg. | 10″ | 5 3/8″ | 4″ | 7.951″ | 6 1/4″ | 6 5/8″ | 3″ | 4 | TAPER | |
API INTERNAL FLUSH (IF)
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 2″ IF | 2 3/8 | 2 1/4 | 1 1/8 | 1.975 | 2 3/4 | 1 1/2 | 2 | 4 | TAPER | |
| 2 3/8″ IF | 3 1/2″ | 3″ | 1 5/8″ | 2.860″ | 3 1/4″ | 2 1/8″ | 2″ | 4 | TAPER | |
| 2 5/8″ IF LH | 3 3/4″ | 3 1/4″ | 1 3/4″ | 3.128″ | 3 5/8″ | 2 1/4″ | 2″ | 4 | TAPER | |
| 2 7/8″ IF | 4 1/8″ | 4 1/2″ | 3 1/2″ | 2 1/8″ | 3.385″ | 3 3/4″ | 2 1/2″ | 2″ | 4 | TAPER |
| 3 1/2″ IF | 4 3/4″ | 4″ | 2 11/16″ | 4.000″ | 4 1/4″ | 3 1/4″ | 2″ | 4 | TAPER | |
| 4″ IF (4 1/2″ XH) | 6″ | 4 1/2″ | 3 1/4″ | 4.828″ | 4 3/4″ | 3 1/2″ | 2″ | 4 | TAPER | |
| 4 1/2″ IF (5″ XH) | 6 1/8″ | 4 1/2″ | 3 3/4″ | 5.250″ | 4 3/4″ | 4″ | 2″ | 4 | TAPER | |
| 5 1/2″ IF | 7 3/8″ | 5″ | 4 13/16″ | 6.390″ | 5 1/2″ | 5 1/16″ | 2″ | 4 | TAPER | |
| 6 5/8 IF | 9″ | 5″ | 3 3/4 | 7.459 | 5 5/8 | 6 1/4 | 2 | 4 | TAPER | |
API FULL HOLE (FH)
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 2 7/8″ FH | 4 1/4″ | 4 1/2″ | 3 1/2″ | 2 1/8″ | 3 7/8″ | 2 1/8″ | 3″ | 5 | TAPER | |
| 3 1/2″ FH | 4 5/8″ | 3 3/4″ | 2 7/16″ | 3.990″ | 4″ | 2 7/8″ | 3″ | 5 | TAPER | |
| 4″ FH | 5 1/4″ | 4 1/2″ | 2 13/16″ | 4.270″ | 4 3/4″ | 3 1/4″ | 2″ | 4 | TAPER | |
| 4 1/2″ FH | 5 3/4″ | 4″ | 3″ | 4.782″ | 4 1/4″ | 3 1/4″ | 3″ | 5 | TAPER | |
| 5 1/2″ FH | 7″ | 5″ | 4″ | 5.828″ | 5 1/2″ | 4 1/4″ | 2″ | 4 | TAPER | |
| 6 5/8″ FH | 8″ | 5″ | 5″ | 6.740″ | 5 1/2″ | 5 1/2″ | 2″ | 4 | TAPER | |
MAYHEW
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| JUNIOR (MJ) | 2 3/4″ | 2 1/4″ | 1 1/4″ | 2.320″ | 2 1/2″ | 1 11/16″ | 2″ | 4 | TAPER | |
| REGULAR (MR) | 3 1/4″ | 3″ | 1 1/2″ | 2.555″ | 3 1/4″ | 2″ | 1 1/2″ | 4 | TAPER | |
| FULLHOLE (MFH) | 3 3/4″ | 3 3/8″ | 2″ | 3.045″ | 3 5/8″ | 2 3/8″ | 1 1/2″ | 4 | TAPER | |
FAILING EXPLORATION
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 2 3/8″ FEDP | 3 1/8″ | 2 3/4″ | 1 3/8″ | 2.480″ | 3″ | 1 3/4″ | 2″ | 4 | TAPER | |
| 2 7/8″ FEDP | 3 3/4″ | 3 1/4″ | 1 7/8″ | 3.100″ | 3 1/2″ | 2 1/4″ | 2″ | 4 | TAPER | |
SQUARE THREAD & DCDMA THREADS
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 3 THREAD N ROD | 2 3/8″ | 2 3/4″ | 1″ | 1.860″ | 3″ | 1 5/8″ | 3 | SQUARE | ||
| 4 THREAD N ROD | 2 3/8″ | 2 3/4″ | 1″ | 1.865″ | 3″ | 1 5/8″ | 4 | SQUARE | ||
| A ROD | 1 5/8″ | 1 7/8″ | 9/16″ | 1.260″ | 2 1/8″ | 1 1/16″ | 3 | SQUARE | ||
| AW ROD | 1 3/4″ | 1 7/8″ | 5/8″ | 1.365″ | 2 1/8″ | 1 1/4″ | 3 | SQUARE | ||
| AWJ (AWML) | 1 3/4″ | 1 3/4″ | 5/8″ | 1.425″ | 1 7/8″ | 1″ | 2″ | 5 | TAPER | |
| E ROD | 1.305″ | 1 3/4″ | 7/16″ | 0.996″ | 2″ | 7/8″ | 3 | SQUARE | ||
| B W | 2 3/8″ | 2 1/4″ | 3/4″ | 1.680″ | 2 5/8″ | 1 3/8″ | 3 | SQUARE | ||
| BQ | 2 3/16″ | 4 3/4″ | 1 13/16″ | 2″ | 1 13/16″ | 1/2″ | 3 | TAPER | ||
| HW | 3 1/2″ | 3 1/4″ | 2 1/4″ | 3 1/2″ | 2 13/16″ | 3 | SQUARE | |||
| EW | 1 3/8″ | 1 9/16″ | 7/16″ | 1.050″ | 1 3/4″ | 7/8″ | 3 | SQUARE | ||
| NW | 2 5/8″ | 2 3/4″ | 1 3/8″ | 2.210″ | 3″ | 2″ | 3 | SQUARE | ||
| NWJ (NWML) | 2 5/8″ | 2 3/8″ | 1 1/4″ | 2.240″ | 2 3/4″ | 1 1/2″ | 2″ | 4 | TAPER | |
Other Sizes
API X-HOLE (XH)
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 3 1/2″ XH | 4 7/8″ | 3 1/2″ | 2 7/16″ | 3.800″ | 3 7/8″ | 2 7/8″ | 2″ | 4 | TAPER | |
| 4 1/2″ XH | 6″ | 4 1/2″ | 3 1/4″ | 4.828″ | 4 3/4″ | 3 1/2″ | 2″ | 4 | TAPER | |
| 5″ XH | 6 1/8″ | 4 1/2″ | 3 3/4″ | 5.250″ | 4 3/4″ | 4″ | 2″ | 4 | TAPER | |
HACKER
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| JUNIOR | 3 1/8″ | 2 1/4″ | 1 7/8″ | 2.685″ | 2 3/4″ | 2 1/8″ | 1 3/4″ | 5 | TAPER | |
| SENIOR | 3 1/2″ | 2 1/2″ | 1 3/4″ | 2.895″ | 2 3/4″ | 2 1/4″ | 1 1/2″ | 4 | TAPER | |
| 4″ HACKER | 5 7/8″ | 3 5/8″ | 3 3/4″ | 5.215″ | 4″ | 4 3/8″ | 1 1/2″ | 4 | TAPER | |
| 6 5/8″ HACKER | 7 1/2″ | 3 1/16″ | 6″ | 6.935″ | 3 1/2″ | 6 1/4″ | 1 1/2″ | 4 | TAPER | |
| 8 5/8″ HACKER | 10 1/2″ | 4 1/2″ | 7 1/2″ | 9.460″ | 5″ | 8″ | 2″ | 4 | TAPER | |
BECO
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 3 1/2″ BECO | 4 3/4″ | 3 3/4″ | 1 1/2″ | 3.970″ | 4 1/4″ | 2 1/4″ | 3″ | 2 | TAPER | |
| 4 1/2″ BECO | 5 3/4″ or 6 1/2″ | 4 1/4″ | 2 1/4″ | 5.000″ | 5″ | 3 1/4″ | 3″ | 2 | TAPER | |
| 5 1/4″ BECO | 7″ | 5 3/4″ | 2 13/16″ | 5.750″ | 5 1/2″ | 3 3/4″ | 3″ | 2 | TAPER | |
| 6″ BECO | 7 5/8″ or 8 3/4″ | 6 1/2″ | 3″ | 6.500″ | 5 1/2″+ | 4 1/2″ | 3″ | 2 | TAPER | |
| 8″ BECO | 10 3/4″ or 12 3/4″ | 4 7/8″ | 5″ | 8.500″ | 5 1/2″+ | 6 1/4″ | 3″ | 2 | TAPER | |
CA-21 (DEEP ROCK)
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| CA 21 | 2 1/4″ | 1 1/4″ | 1 1/8″ | 1.765″ | 1 1/2″ | 1 1/2″ | 1 1/2″ | 6 | TAPER | |
E U E
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 3/4″ (1.050″ API) | 1.560″ | 1 1/8″ | 1.315″ | 0.825″ | 1 3/8″ | 3/4″ | 10 | TAPER | ||
| 1″ (1.315″ API) | 1.900″ | 1 1/4″ | 1.469″ | 1.049″ | 1 1/2″ | 3/4″ | 10 | TAPER | ||
| 1 1/4″ (1.660″ API) | 2.200″ | 1 3/8″ | 1.825″ | 1.380″ | 1 3/4″ | 1 1/2″ | 3/4″ | 10 | TAPER | |
| 1 1/2″ (1.900″ API) | 2.500″ | 1 7/16″ | 2.093″ | 1.610″ | 1 7/8″ | 1 3/4″ | 3/4″ | 10 | TAPER | |
| 2″ (2 3/8″ API) | 3.063″ | 1 15/16″ | 2.625″ | 1.995″ | 2 3/8″ | 2 1/4″ | 3/4″ | 8 | TAPER | |
| 2 1/2″ (2 7/8″ API) | 3.668″ | 2 1/8″ | 3.113″ | 2.441″ | 2 1/2″ | 2 1/2″ | 3/4″ | 8 | TAPER | |
| 3″ (3 1/2″ API) | 4.500″ | 2 3/8″ | 3.795″ | 2.992″ | 2 3/4″ | 3 5/16″ | 3/4″ | 8 | TAPER | |
| 3 1/2″ (4″ API) | 5.000″ | 2 1/2″ | 4.250″ | 3.476″ | 2 7/8″ | 3/4″ | 8 | TAPER | ||
| 4″ (4 1/2″ API) | 5.563″ | 2 5/8″ | 4.790″ | 3.958″ | 3″ | 3/4″ | 8 | TAPER | ||
HACKER FAILING
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 6 5/8″ HF | 8″ | 3 1/2″ | 6″ | 7.310″ | 4 1/2″ | 6 1/2″ | 1.5″ | 4 | TAPER | |
MOBILE
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 2 5/8″ MOBILE | 2 5/8″ | 2 1/2″ | 1 1/4″ | 2.240″ | 2 7/8″ | 1 3/4″ | 2″ | 5 | TAPER | |
NATIONAL PIPE THREAD
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 1″ NPT | 1 3/4″ | 1″ | 1″ | 1.325″ | 1 1/4″ | 1 1/8″ | 3/4″ | 11 1/2 | TAPER | |
| 1″ NPT LH | 1 3/4″ | 1″ | 1″ | 1.325″ | 1 1/4″ | 1 1/8″ | 3/4″ | 11 1/2 | TAPER | |
| 1 1/4″ NPT | 2″ | 1″ | 1 1/4″ | 1.660″ | 1 1/4″ | 1 3/8″ | 3/4″ | 11 1/2 | TAPER | |
| 1 1/2″ NPT | 2 1/4″ | 1 1/8″ | 1 1/2″ | 1.950″ | 1 3/8″ | 1 5/8″ | 3/4″ | 11 1/2 | TAPER | |
| 2″ NPT | 2 3/4″ | 1 1/8″ | 2″ | 2.385″ | 1 5/8″ | 2 1/8″ | 3/4″ | 11 1/2 | TAPER | |
| 2″ NPT LH | 2 3/4″ | 1 1/8″ | 2″ | 2.385 | 1 5/8″ | 2 1/8″ | 3/4″ | 11 1/2 | TAPER | |
| 2 1/2″ NPT | 3 1/4″ | 1 9/16″ | 2 1/2″ | 2.875″ | 1 3/4″ | 2 5/8″ | 3/4″ | 8 | TAPER | |
| 3″ NPT | 4″ | 1 5/8″ | 3″ | 3.500″ | 1 7/8″ | 3 1/8″ | 3/4″ | 8 | TAPER | |
| 3″ NPT LH | 4″ | 1 5/8″ | 3″ | 3.500″ | 1 7/8″ | 3 1/8″ | 3/4″ | 8 | TAPER | |
| 3 1/2″ NPT | 4 5/8″ | 1 11/16″ | 3 1/2″ | 4.000″ | 2 1/16″ | 3 5/8″ | 3/4″ | 8 | TAPER | |
| 3 1/2″ NPT LH | 4 5/8″ | 1 11/16″ | 3 1/2″ | 4.000″ | 2 1/16″ | 3 5/8″ | 3/4″ | 8 | TAPER | |
| 4″ NPT | 5 1/4″ | 1 3/4″ | 4″ | 4.510″ | 2 1/4″ | 4 1/8″ | 3/4″ | 8 | TAPER | |
| 4″ NPT LH | 5 1/4″ | 1 3/4″ | 4″ | 4.510″ | 2 1/4″ | 4 1/8″ | 3/4″ | 8 | TAPER | |
| 4 1/4″ NPT | 4 1/4″ | 4.250″ | 3/4″ | 8 | TAPER | |||||
| 5″ NPT | 6 5/16″ | 2″ | 5″ | 5.563″ | 2 1/2″ | 5 1/4″ | 3/4″ | 8 | TAPER | |
| 6″ NPT | 7 3/8″ | 2″ | 6″ | 6.625″ | 2 1/2″ | 6 1/4″ | 3/4″ | 8 | TAPER | |
PK RED DEVIL
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| P K Red Devil | 2 7/8″ | 3 7/8″ | 1 3/8″ | 2.300″ | 4 1/4″ | 1 7/8″ | 3/4″ | 8 | TAPER | |
ROCKMASTER
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| ROCKMASTER | 2 3/4″ | 3″ | 1 1/8″ | 2.030″ | 3 1/4″ | 1 3/4″ | 3 | ACME | ||
WINTER WEISS
| Material | Pin Dimensions | Box Dimensions | Thread | |||||||
| Tool Joint Name & Nominal Size | O.D. | Make to Dia. | Pin Length | Pin ID | Pin Dia. @ Base | Box Length | Box Max ID | Taper | Thread / Inch | Thread Form |
| 2 3/8″ WW Mod. | 3 1/4″ | 3″ | 1 1/2″ | 2.535″ | 3 1/4″ | 2″ | 1.5″ | 4 | TAPER | |
| 2 7/8 WW Mod. | 3 7/16″ | 3″ | 1 1/2″ | 2.535″ | 3 1/4″ | 2″ | 1.5″ | 4 | TAPER | |




