Breakout Wrench
Breakout wrenches are available in multiple configurations for loosening and tightening and rotary drill rod.
Weld-on or Thread-on Tool Joint Subs
Weld-on or Thread-on Tool Joint Subs are designed with one end to shrink fit or screw onto the end of your drill tube and then be welded. The opposite end is the pin or box connection of your choice. Pin or Box to Blank Subs are similar in use to the above subs. They have […]
Tool Joint Thread Chart
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 […]
Stock Subs
The Subs listed below are what we consider to be stock standard sizes and the working length will accept standard break out flats. All of our subs are manufactured from 4142 heat treated alloy steel on computerized lathes enabling us to offer better pricing and availability. Many other sizes are available in a multitude of […]
Shock, Floating, Cushion, and Special I.D. Subs
Shock Subs are specialized subs designed to absorb the shock vibrations created by a down-hole hammer and to prevent damage to the drill string and the top head drive. Floating or Cushion Subs absorb shock vibrations transmitted up through the drill string built to protect the pipe. Their construction is simpler with more vertical movement […]
Kelly Saver Subs
Kelly Saver Subs refer to a sub used between the Kelly or top head drive and the drill pipe. It is usually a pin to pin sub that takes the wear abuse to protect the drill pipe and the drive connection. Mills can furnish these subs along with the fluted, hex, or square Kelly Bar […]
Float Valve Subs
Float Valve Subs are bored to a larger I.D. to suit a Float Valve. They can be placed anywhere in the drill string to maintain the circulation in one direction.
Elevator Lift Subs
Elevator Lift Subs typically feature an hour glass shape and are turned down in the middle section to match the size of elevator being used. They typically have a male pin thread on the bottom and a blank end on top, the turned down side of the blank end is usually tapered or square shoulder […]