1, flat drill: the past in the factory is widely used in a deep hole drill. The drill is simple in structure and easy to manufacture. In use in addition pipe, water pump, without other auxiliary tools, so it is convenient to use, suitable for small batch production. Under the action of a certain pressure, the chip is eliminated from the inner hole of the work piece, and no need to remove the chip, so the continuous drilling can be cut off. Deep hole drilling with low precision and low surface roughness,
Flat drill series
In addition, there is a flat drill with a guide bar, a guide strip on the knife body in the Kong Zhongqi guiding role, to prevent drilling hole deviation.
2, gun drill (single edge chip outside the long hole drilling): the drill bit is now cemented carbide, the past is high speed steel, welded and seamless steel pipe. High pressure cooling lubricating liquid by the crescent shaped hole of the drill pipe through the front end of the drill hole injection to the cutting area, and chip through the 120o trough scouring discharge.
Gun drill series
The bit is that it only has a cutting edge on one side of the drill axis, thus eliminating the adverse effects of the cross cutting edge on the cutting process. The cutting force is supported by the two guide block and the hole wall of the workpiece. When the workpiece is cut, the positioning of the guide sleeve is made. When the guide block is in the hole of the work piece, the guide is positioned by the hole. The main cutting edge is basically through or slightly lower than the bit center, about (0.01 ~ 0.015) the diameter of the drill bit. Maximum not more than 0.4mm. It's inside and outside angle of cutting edge is 0o, after the angle of 0=10o ~ 15O, and double angle grinding. The blade angle of Kr1=60o ~ 65o, Kr2=110o ~ 115o in the blade angle, blade tip distance e=d/4 (d diameter).
Deep application of carbide gun drill for drilling of diameter 2 ~ 30mm in diameter. Drilling cutting speed (steel) Vc=70 ~ 120m/min, feed f=0.01 ~ 0.04mm/r, feed F and bit diameter D is proportional to.
Chip removing deep hole drill
3, single edge chip removal hole drilling:
This drill for drilling diameter of more than 25mm. In the drill bit is set with two hard alloy guide block, the guiding and supporting function. In the main blade into the ladder, and the grinding groove, the cutting apart and break, favorable chip discharge. The cutting edge of the cutting edge is straight through the hole of the chip, and the chip is discharged from the inner hole of the drill pipe under the action of the pressure cutting fluid. This kind of drilling bit is of good rigidity, smooth drilling, high speed drilling, and the surface roughness can reach Ra3.2 m, and the dimension precision can reach IT10 ~ IT11. Cutting dosage is 80m/min ~ f=0.06, Vc=60 ~ 0.12mm/r.
4, the wrong tooth (multi blade) inside the chip removing deep hole drilling:
This bit is the tooth cutting edge stagger breakdown at both sides of the bit, to ensure reliable chip and to reduce the size of the chip, which is convenient for discharging. And the cooling condition of the blade is improved. The radial force on the cutting edge is also balanced. At the same time, according to the cutting edge of the cutting conditions, the use of different cutting tool materials (grades), in order to achieve the best cutting effect.
There are two hard alloy guide and support block on the drill bit. Geometric parameters are: 2 T = 144 + db4o, 72 o Kr1 PRG, Kr2=110o, e=0.1d, gamma 01=0o, Kr '=0o, ~ gamma 02=5o 8O. ~ alpha 0=8o 12O. ~ lambda t2=5o 8O. B alpha 1 = 1 ~ 1.5mm, br1=1.2 ~ 2mm, h=0.4 ~ 0.5mm, r = 1 + 0.1 mm, tau =2o ~ 6O, before the outer edge in the middle of the odontoid process quantity for (1 ~ 2) f.
The cutting amount of the drill bit is Vc=70 ~ 100m/min, f=0.15 ~ 0.35mm/r.
5, spray suction drill: as shown in figure 7. It is in the chip removal system using the principle of spraying, to improve chip removal conditions, the pressure of the cooling fluid compared with the previous three kinds of low, as shown in figure 8. It can be used for drilling diameter of 20 ~ 65mm of length to diameter ratio of 100 deep, and high processing efficiency. In addition to the blade welded drill for hard alloy, can also be used to drill into a jet drill.
Spray and suction drilling work principle, with certain pressure cutting fluid, by oil inlet into the connecting device, most of them through the gap between the inner and the outer tubes, after a bit of six holes, from the annular section and throat neck (back pressure area clearance) flow to the cutting area, cutting edges of the cooling and the chip into chip export, the pipe flow backwards. A crescent groove and a small portion of the cutting fluid from the tube around the backward jet velocity increases, and the formation of jet. According to the principle of conservation of energy, due to the specific energy increases, pressure drop, so in the jet flow around the formation area of low pressure. This tube, the front end and the rear end of the pressure difference, the suction, acceleration at the front end of the cutting chip cutting fluid flow backward discharge.
Cutting the amount of cutting drilling in the general steel, Vc=70 ~ 100m/min, f=0.1 ~ 0.17mm/r.
All of the above drill bits can be continuously drilled without cutting back and cooling and lubricating, high processing efficiency and good quality of the holes, but must have the corresponding hydraulic system for cooling and lubricating and chip removal.
6 and twist drill: in no special tooling and piece production, available standard twist drill with a long rod to drilling. But because of the twist drill chip space and channel, not a row of chips and the cooling lubrication, so must repeatedly chip and lubrication, and increase the ratio of the drill bit is many times the auxiliary time, to make the processing efficiency is low. But it does not need other tools, operating technology is relatively simple, so it is a single piece of production often used in deep hole drilling tool.
The drill hole should pay attention to the problem:
The diameter of drill pipe D should be less than 0.3 to 0.8mm of the bit diameter, and the outer surface must be smooth. The rolling process for the diameter of more than 20mm to improve the drill pipe, drill pipe surface hardness, prevent cutting debris injury.
The diameter of the A segment of the taper shank drill bit should be smaller from 0.5 to 1mm, as shown in Figure 9, in case of the process of drilling.