Kobald Mining Services offers a wide range of premium alloys reverse circulation subs. All subs are designed and manufactured using the latest modern techniques, to maximize performance and durability. Reverse Circulation subs are available in a variety of sizes with Remet/Metzke thread connections, but we can also manufacture for you some custom-made subs.


Kobald Mining Services RC subs ensure long life and compatibility

Saver Subs

A saver sub is usually positioned at the top of the rod string, between the first rod and the top drive head assembly. This position in the string is subject to much wear, so saver sub was designed to be an inexpensive, easily replaceable part.  In this way, it is used to protect the threads on the actual rod and allows for a quick replacement and short shutdown onsite operation.  Using saver sub from Kobald Mining Services Ltd. offers great advantages allowing you to drill in the best operating conditions wearing the sub and not the thread of the rod.



Adapter Subs

Adapt from the Spindle / Shaft to the drill string

Digout Subs

Kobald’s digout sub results from extensive operational testing. Its unique design ensures the preciseness of the thread enabling the stability and accuracy during drilling operations. Many of our customers achieved very good results.

Try it to convince yourself of our best available tools!

Cross-over Subs

A cross over sub is used to protect other tooling in your drill string to deliver outgoing air to the bit face during RC drilling. Kobald’s cross over subs are phosphated and have wrench flats milled into them to allow for better assembly and disassembly.

Blow-down Subs

Blow-down sub is used at the surface to redirect the compressed air down the inner tube in an effort to dislodge sample in the interchange slot or rock bit adaptor, which is blocking the sample extraction.

Blow-up Subs

To re-direct air up inner tube for tube blockages

Tri-Cone Sub

Drive Subs

The drive sub retains the bit within the bottom of the hammer and transmits rotational drive torque to the bit.