1000mm deep hole drilling for steel and aluminum parts

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Specially used for drilling deep holes. In machining, the hole with a ratio of hole depth to hole diameter greater than 6 is usually called a deep hole. When deep hole drilling, heat dissipation and chip removal are difficult, and because the drill rod is slender and rigid, it is prone to bending and vibration. Generally, the pressure cooling system must be used to solve the cooling and chip removal problems.

Processing characteristics of deep holes

1. The shank is slender and has poor rigidity, and it is difficult to cool and remove chips.
2. Since the tool cuts in the hole, the cutting condition and tool wear cannot be observed.

Deep hole drilling method

1. Gun hole drill with a diameter of 3-20mm.
2. With a diameter of 20～65mm, use high pressure internal chip removal deep hole drill or jet suction drill, or use indexable insert staggered tooth deep hole drill.

Deep hole drills are divided into two types: external chip removal and internal chip removal according to chip removal methods. Gun drills, deep hole flat drills and deep hole twist drills are used for external chip removal; gun drills are used for internal chip removal.

The processing system is different, including BTA deep hole drilling, jet drilling and DF deep hole drilling.

① Gun drill: There is only one cutting part, which was first used for processing gun barrels. When drilling, the cutting fluid enters from the middle of the drill pipe, sprays into the cutting area through the small hole of the drill head, and then discharges the cutting chips from the V-shaped groove of the drill. Gun drills are suitable for processing deep holes with a hole diameter of 2-20 mm and a ratio of hole depth to hole diameter greater than 100.

②BTA deep hole drilling: cutting fluid is fed in from the gap between the drill pipe and the hole wall, and the cutting fluid is discharged from the inner hole of the drill pipe by the pressure of the cutting fluid. BTA deep hole drills are suitable for drilling deep holes with a hole diameter of 6 mm or more, and the ratio of hole depth to hole diameter is less than 100. Its production efficiency is more than 3 times higher than that of gun drills.

③ Jet drill: a multi-blade internal chip removal deep hole drill with two layers of inner and outer drill pipes. Most of the cutting fluid enters the cutting area from the gap between the inner and outer drill pipes, and then enters the inner pipe together with the chips; the other A small part of the cutting fluid enters the inner tube through the crescent-shaped hole at the end of the inner tube, producing a jet effect, forming a low pressure area, and helping to suck the chips. Jet drilling does not require a strict cutting fluid sealing device, and is suitable for drilling deep holes with a diameter of 18 mm or more and a hole depth and an aperture ratio of less than 100.

④DF deep hole drill: This kind of drill bit absorbs the advantages of BTA deep hole drill and jet drill. It adopts a single tube. The chip removal depends on the dual action of pushing and suction, which improves the chip removal ability. It can drill holes with a diameter of 8 mm or more. Deep hole.

Gun drills are usually made of high-speed steel or cemented carbide. Various types of internal chip removal deep hole drills can be welded or mechanically clamped with indexable cemented carbide blades according to the size. The guide block on the deep hole drill plays the role of guiding and centering, reducing the deflection of the hole and the vibration during cutting. The arrangement of the teeth and guide blocks of the deep hole drill mainly considers the balance of chip separation and radial force during cutting. The cutter body and the drill rod can be connected by welding or square thread.