Pullback system for drilling tool

A pullback system comprising:

• a pullback device configured for product attachment and including a plurality of arms;
• and
• a rotary drill bit for use with a horizontal directional drill string, the rotary drill bit comprising:
• a coupler provided at a proximal axial end and configured to attach the rotary drill bit to a drill head at a distal end of the drill string,
• a cutting portion provided at a distal axial end and provided with a plurality of vanes with respective cutters that operate to cut a hole in earth when the rotary drill bit is rotated about a central axis, wherein the plurality of vanes project radially outwardly from a surface of the cutting portion such that the surface forms respective troughs circumferentially interspersed with the plurality of vanes, and
• a plurality of engagement features positioned axially within the cutting portion and radially inward of an outer cutting diameter to facilitate attachment of the pullback device without removing the rotary drill bit, or any portion thereof, from the drill head,
• wherein the pullback device is removably attachable to the rotary drill bit and the plurality of arms are engageable with the respective plurality of engagement features, the plurality of arms positioned entirely within the respective troughs, and radially inside of the plurality of vanes, throughout the cutting portion when attached,
• wherein the plurality of engagement features are positioned such that the pullback device attaches at an axial position offset from the distal axial end of the rotary drill bit.

A method comprising:

• operating a horizontal directional drilling machine to thrust a drill string having a rotary drill bit into the earth to drill an underground hole from a start location to an end location, the rotary drill bit having a cutting portion defined by a plurality of vanes projecting radially outward from a surface to define an outer cutting diameter;
• at the end location, attaching a pullback device to a plurality of engagement features of the rotary drill bit at respective positions that are offset from a distal axial end of the rotary drill bit, axially within the cutting portion, the attached pullback device extending axially beyond the distal axial end of the rotary drill bit, without extending radially beyond the plurality of vanes;
• attaching a product to an attachment portion of the pullback device at the end location;
• pulling the drill string, including the rotary drill bit, the pullback device, and the product, back through the underground hole from the end location to the start location to install the product into the underground hole;
• and
• detaching the product from the pullback device at the start location.