1. External chip drilling rod (compatible with gun drill)
Structure: Hollow drill rod+outer V-shaped chip groove, wall thickness 3-8mm, mostly made of 42CrMo alloy steel pipe.
Working mode: The coolant is injected from inside the drill rod, and the chips are discharged outward along the V-shaped groove.
Adaptation: Gun drill, apertureφ 2-φ 50mm， Deep processing of small holes with a depth to diameter ratio of 300:1.
Characteristics: The chip removal channel is independent, but the rigidity of the drill rod is slightly lower than that of the internal chip removal type, and the aspect ratio needs to be controlled.
2. Internal chip removal drill rod (compatible with BTA/spray suction drill/DF drill)
Structure: Thick walled hollow tube (without external grooves), with an inner diameter of 1/2 of the aperture to ensure the passage of chips.
Working mode: The coolant is injected into the gap between the drill rod and the hole wall, and the chips are discharged from the inside of the drill rod.
Adaptation: BTA drill (6mm or more), spray suction drill (18mm or more), DF drill (8mm or more).
Features: Stronger rigidity, suitable for processing with large aperture and large aspect ratio (aspect ratio≤ 100:1), smoother chip removal.
3. Universal extended drill rod (suitable for ordinary deep hole machining)
Structure: Solid or hollow elongated design with standardized interfaces (Mohs taper/BT interface).
Adaptation: ordinary extended Fried Dough Twists drill, worm shaped drill, medium shallow deep holes with a depth diameter ratio of 5-20 times.
Features: Low cost, strong universality, no need for high-pressure cooling system, suitable for small and medium-sized batch processing.