What are the main components of double tube drilling tools
Double tube drilling tool accessories mainly include the following categories:
1. Joint type
Upper joint: connects the drill rod and the double tube drilling tool, with some equipped with movable environmental protection diameter, and others with slotted and embedded alloy plates on the joint to maintain diameter. Its function is to transmit power and enable the drilling tool to rotate.
Double tube drilling tool accessories mainly include the following categories:
1. Joint type
Upper joint: connects the drill rod and the double tube drilling tool, with some equipped with movable environmental protection diameter, and others with slotted and embedded alloy plates on the joint to maintain diameter. Its function is to transmit power and enable the drilling tool to rotate.
Water distribution joint: commonly used in piston type single action double tube drilling tools, used to control the flow of flushing fluid, so that the flushing fluid can enter the borehole according to a specific path and carry rock powder back out of the hole.
2. Pipe body type
Outer tube: It is the outer tube of a dual tube drilling tool, mainly used to transmit drilling pressure and torque, connect the drill bit, and rotate with the rotation of the drilling rig during the drilling process.
Inner tube: It is the inner tube of a double tube drilling tool, used to accommodate rock cores. In a single action double tube drilling tool, the inner tube remains stationary during the drilling process to avoid disturbance to the rock cores.
Lining tube: lined inside the inner tube, usually made of transparent organic material, for easy core retreat and maintaining the integrity of rock and mineral cores.
3. Drill bits
Ordinary drill bits: Depending on different geological conditions and drilling requirements, there are various types, such as hard alloy drill bits, steel grain drill bits, etc., used for crushing rocks.
Ladder drill bit: commonly used in piston type single action double tube drilling tools, its outlet hole design helps to circulate the flushing fluid and carry rock powder back out of the hole.
4. Card core devices
Card spring: used to hold rock cores and prevent them from falling out of the core tube during drilling. It comes in various forms such as standard and basket types.
Card spring seat: used for installing card springs. The distance between the card spring seat and the inner step of the drill bit needs to be adjusted according to the actual situation to ensure the card center effect.
Compression card device: such as piston type and ball clamp type compression card devices, when the rock core is mined at the end of the cycle, steel balls are injected to force the core breaker to forcefully clamp the rock core with the flushing liquid.
5. Other accessories
Reamer: also known as a reaming shell, used to enlarge the diameter of a borehole, ensuring that the diameter of the borehole meets the requirements, while also helping to reduce friction of the drilling tool in the borehole.
Single acting bearings: In single acting dual tube drilling tools, single acting bearings play a role in enabling the inner and outer tubes to move relatively independently, ensuring that the inner tube does not rotate during drilling.