The Drill Bit bit is a tool used to Drill Bit holes or blind holes in the solid material and to reaminate the holes. Commonly used Drill Bit bit mainly twist Drill Bit, flat Drill Bit, center Drill Bit, deep hole Drill Bit and nesting Drill Bit bit. Reaming Drill Bit bits and countersunk Drill Bit bits can not Drill Bit holes on solid materials, but they are also routinely classified as Drill Bits. Printed board Drill Biting bits are generally used carbide, because the epoxy glass cloth complex copper plate on the tool wear particularly fast. The so-called carbide Drill Bit bit is based on tungsten carbide powder as a matrix, cobalt powder as a binder by pressing, sintering made. Usually containing tungsten carbide 94%, cobalt 6%.
Because of its high hardness, very wear-resistant, have a certain strength, suitable for high-speed cutting. But the toughness is poor, very brittle, in order to improve the performance of cemented carbide, and some used in the carbonization of the matrix vapor deposition of a layer of 5 to 7 microns of special hard titanium carbide (TIC) or titanium nitride (TIN), With higher hardness. Some use of ion implantation technology, titanium, nitrogen, and carbon into the substrate of a certain depth, not only to improve the hardness and strength and re-grinding in the Drill Bit when these injections can also move. There is also a physical method in the top of the twist Drill Bit to generate a layer of diamond film, greatly improving the hardness and wear resistance of the Drill Bit.
The hardness and strength of the cemented carbide are not only related to the ratio of tungsten carbide to cobalt, but also to the particles of the powder. Ultra-fine particles of carbide Drill Bit, the average size of its tungsten carbide grain size below 1 micron. This bit, not only high hardness and compression and bending strength are improved. In order to save costs Now many Drill Bit bits with welded handle structure, the original Drill Bit bit as a whole are carbide, and now the rear of the Drill Bit handle with stainless steel, the cost greatly reduced but due to the use of different materials, the dynamic concentricity is less than the overall hard Alloy Drill Bit bits, especially in small diameter.
The Drill Bit bit is a widely used hardware for our engineering machinery. It is used to Drill Bit holes or blind holes in the solid material and to Drill Bit holes in existing holes. But different operating environment we choose the different types of Drill Bit bit, commonly used Drill Bit bit are twist Drill Bit, flat Drill Bit, center Drill Bit, deep hole Drill Biting and nesting Drill Bit.
Twist Drill Bit is the most widely used hole machining tool. Usually in the range of 0.25 to 80 mm in diameter. It consists mainly of working parts and handles. The working part has two spiral grooves, shaped like twist, hence the name. In order to reduce the friction between the guide part and the hole wall during the Drill Biting, the twist Drill Bit is gradually tapered from the Drill Bit tip toward the handle. The helix angle of the twist Drill Bit mainly affects the size of the rake angle, the flap strength and the chip removal performance, usually 25 ° ~ 32 °. The helical groove can be machined by milling, grinding, hot rolling or hot extrusion. The front end of the Drill Bit is sharpened to form the cutting part. Standard twist Drill Bit part of the cutting angle of 118, horizontal blade angle of 40 ° ~ 60 °, the rear angle of 8 ° ~ 20 °. Due to structural reasons, the rake angle at the outer edge of the large, gradually reduced to the middle, the horizontal edge at the negative rake angle (up to -55 °), Drill Biting from the extrusion effect. In order to improve the cutting performance of the twist Drill Bit, the cutting part can be ground into various shapes (such as group Drill Bits) according to the nature of the material being processed. Twist Drill Bit handle in the form of two kinds of straight handle and taper shank, the former is caught in the Drill Bit chuck, the latter inserted in the machine tool spindle or tailstock cone hole. General twist Drill Bit made of high speed steel. Inlaid carbide or blade crown twist Drill Bit for processing cast iron, hardened steel and non-metallic materials, etc., the overall carved carbide twist Drill Bit for processing instrument parts and printed circuit boards and so on.
The cutting part of the flat Drill Bit is a spade, simple structure, low manufacturing cost, easy cutting of the cutting fluid into the hole, but poor cutting and chip removal performance. The structure of the flat Drill Bit is both monolithic and assembled. The overall type is mainly used for Drill Biting holes with a diameter of 0.03 to 0.5 mm. Assembly of flat Drill Bit blade can be replaced, can be used within the cooling, mainly for Drill Biting diameter of 25 to 500 mm large holes.
Deep hole Drill Biting is usually refers to the processing hole depth and aperture ratio of more than 6 holes of the tool. Commonly used gun Drill Bit, BTA deep hole Drill Biting, jet Drill Biting, DF deep hole Drill Biting and so on. Casing Drill Bit is also commonly used for deep hole machining.
Drill Biting holes are 3 to 4 teeth, the rigidity than the twist Drill Bit, used to expand the existing holes and improve the processing accuracy and finish.
Countersunk Drill Bit with more teeth, the forming method to the end of the hole into the required shape for the processing of a variety of countersunk head screw head hole, or flatten the hole outside the end of the face.
Center Drill Bit for the Drill Biting shaft of the workpiece center hole, it is essentially a small spiral angle twist Drill Bit and countersink Drill Bit compound, it is also known as composite center Drill Bit.
The middle of the hollow Drill Bit pipe is a hollow Drill Bit bit, mainly used for Drill Biting core.