Reverse Circulation Subs

Hole Products offers a wide range of reverse circulation subs. All subs are manufactured using premium alloys and the most advanced manufacturing techniques, to maximize performance and durability. Reverse Circulation subs are available in a variety of sizes and with all industry standard thread connections. Our standard sub offering includes saver subs, adapter subs, cross-over subs, and bit subs. Custom subs are also available to meet all Reverse Circulation system requirements.

Saver Subs

Saver Subs are positioned at the top of the Reverse Circulation rod string, between the first rod and the top drive head assembly. The subs purpose is to protect the top drive head threads from the wear and tear of frequent make and break connections during the drilling cycle.

Cross-Over Subs

Cross-over Subs allow the use of conventional DTH hammer in Reverse Circulation drilling. When used in conjunction with a crossover sub mounted above the hammer, the cuttings move up from the bit face into the inner tube through the open slots located on the crossover sub. Crossover subs can also be used to adapt between the rod string and hammer if they are different thread patterns.

Adapter Subs

Adapter Subs are used to adapt between multiple
tooling sizes and thread profiles. Adapter subs can be manufactured in a wide range of sizes and styles, and
with any thread connection.

Bit Subs

Bit Subs connect the Reverse Circulation rod string to the rock bit. Bit subs are available in two designs: one, as an adapter to connect the rod string to the bit for drilling in overburden, and two, as a sub with an inner tube designed to direct the sample up the inner tube of the rods, to the surface for collection.