Directional drilling machines (also referred to as drill rigs, boring machines, or drills) are available in many sizes. Regardless of the size, they all have three main functions:

 

• Thrust
• Pullback
• Rotation
  

 

Although the industry-wide standard for rating the size of a machine is the pullback capability, the main function is rotation. Because most of the succeeded project records show that maximum 30% of pullback force capacity has been used but it is not valid for the torque power need.

It is possible to categorize Directional drilling machines typically used for environmental applications in three main group:

 

• Mini rigs ( ... < 15 tons = 33000 lbs )
• Midi rig   ( 15 < ... < 60 tons = 135000 lbs )
• Maxi rigs ( 60 < … tons)
  

 

The HDD industry has machines much larger than 1,000,000 lbs for special crossings.

A small drilling machine usually has integrated components consisting of the power unit, drill pipe, and automated rod loader.

The small rigs are quite popular because of the mobility and reduced setup time.

Maxi rigs are quite complicated to manage. Even transportation is required a well organization. Rig and equipments are carried by at least 3 trucks. Depends on the size of rig, this number could be increased up to 8. Mostly they are desinged like a trailer because of easy set up facility.

Loading and unloading drill pipes is achieved by cranes.

Power packs are too big to carry on the rig. That’s why they are transported with big containers and after set up power packs and rig are connected with hydrolic hoses.

Not only power packs are separeted from rig but also high pressure pumps are independent from the rig.