Views: 100 Author: Site Editor Publish Time: 2021-11-01 Origin: Site
Drilling refers to the operation of drilling holes in solid materials with a drill. The drill bit is a cutting tool for drilling, usually made of high-speed steel, and the working part is hardened to 62~65HRC after heat treatment. Generally, a drill consists of a shank, a neck and a working part.
Metal hole grinder and metal polishing grinder are commonly used for metal drilling.
Under normal circumstances, the chips will be carried away by the groove of the drill bit and away from the tip of the metal grinding bits. The cutting edge generates more chips, and these chips continue to move the chips outward from the hole. Sometimes cutting fluids are used to alleviate this problem and extend tool life by cooling and lubricating the tool tip and chip flow. Coolant may be introduced through holes in the drill pipe, which is common when using gun drills. Especially when cutting aluminum, the cutting fluid helps to ensure that the holes are smooth and accurate, while preventing the metal from jamming the drill bit during the drilling process.
For heavy-duty and deep holes, use an oil hole drill in the drill. The lubricant is pumped into the drill bit through the small hole in the drill bit and flows out along the groove. Conventional metal grinding disc for drill can be used for oil hole drilling, but it is more common in automatic drilling machines, where the workpiece is rotated instead of the drill.
In computer numerical control (CNC) machine tools, the process of deep drilling or intermittent cutting is used to prevent harmful accumulation of chips when drilling deep holes (when the depth of the hole is about three times the diameter of the drill).
Wood is softer than most metals, so drilling holes in wood is much easier than drilling holes in metal. The most notable feature is that it does not use cutting fluid. The main problem with wood drilling is to ensure that the inlet and outlet holes are clean and prevent burning.
Twist drill bits also work well in wood, but they tend to chip off the wood at the entrance and exit of the hole. Many special drills for drilling holes in wood have been developed, including Brad point drills, Fosterner drills and hole saws. For drilling holes in wood, the commonly used tools mainly include wood grinding machine, hand crank metal grinder, wood buffer polisher and electric pen grinder.
In fact, manual electric grinder is very practical for metal drilling and wood drilling. The electric grinder is a high-speed tool, which will produce vibration during operation, and will produce a large amount of debris and powder during cutting. When the cutting temperature is too high, it will also cause the workpiece to melt, decompose or even burn. Therefore, before using the electric grinder, it is necessary to do the following protections. The electric grinder can complete the leveling, cleaning, grinding, polishing, drilling, milling, cutting and cutting of small and medium-sized workpieces by replacing various accessories and auxiliary parts. Although inaccurate and vibrating, it is an indispensable hand tool because of its small size and flexible operation. The electric rotary hammer drill is also a practical tool.