A drilling is a process to make a hole inside the metal, wood, plastic etc with the help of drill tool is called drilling. A drilling operation is done by drill machine & drill bit. Drill bit also an important part in the world of cutting tools. The drill bit is used to make cylindrical hole inside the metal. This bit is hold by chuck & chuck provides a torque and axial force. After that when drill & work piece come in contact then operation is done. During a drilling process a high temperature is induced. To reduce this high temperature we used coolant. The shank is direct fit into drill chuck and hold tightly.
GEOMETRY OF DRILL BIT: - now we are discuss about geometry of drill bit. First important part of a drill bit is spiral. Its control the rate of metal removal or we can say chips removal rate. A fast spiral is used for a feed rate under small rpm of a drill machine. Sometimes we need a high speed of a drill machine to use on some soft metal aluminum & woods.
Another main point is point angle. This is a angle between metal & tip of drill bit. Hard material mild steel, cast iron, need a large angle and soft materials like woods, aluminum need a sharp angle during operation. Now we are discuss about lip angle. Lip angle decide the rate of metal removal from a job. A greater lip angle may be the reason of blunt of a tool. It may be the reason of a tool failure. Sometimes it depends on length of bit. It’s totally depending on how long a hole can be drill. Drill bits are available in 3 categories mainly.
1) Screw machine length ( Short Length)
2) Common Length ( Medium Length)
3) Long Series ( Long Length)
MATERIALS: - The drill bits are available in many hard materials. It’s also depending on our application & our requirements. The drill bits are available in carbon steel. But the hardness of these types of bit is not so good. It’s mainly used for wooden, plastic, softwoods etc. bits are available in high speed steel. This material is back bone of machine tools. It also used on a wide level for industrial purpose. High speed steel has good hardness properties. Most of cutting tool is made by high speed steel. The drill bits are used for drilled cast iron, mild steel, hard wood & carbon steel. It’s also working very well on very high speed. Now we discuss about tungsten carbide. This material is very hard & costly. Carbide is more brittle then carbon steel, high speed steel. This is used to make tips for drills, single point cutting tool. Only a tip is enough to drill a very hard material. Now I am talking about world’s hardest material. I mean diamond. Diamond is the hardest material in the world. Its very tuff and costly & and having all cutting tool properties. Whole tool is not made up of diamond. Only a small tip is used for to make tool tip as like carbide. It consists of a layer of diamond particles typically about (0.5 to 0.020) thick by tungsten carbide. Diamond bits are typically used in the automotive industries, aerospace and mechanical industries. Carbide and diamond drill bits are used in cnc machine and automation. The bit is hold in tool magazine & a particular coding is set for it. The coding is done by G codes and M codes. G is defined the number of tool & M is defined the sequence of operation.
Lots of industries manufacture the drill bits like Miranda tools & HMT I the major brand.
Warning:- During the drilling operation a drill bit is contact with work piece and produced a very high temperature . Because of this high temperature a tool may be melt or blunt. So there is a proper coolant supply we need during operation. Our coolant is soluble oil, mineral oil, diesel, water etc.
Our Major Brands of HSS Drills are: