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Drilling
Drilling is a cutting process where a drill bit is spun to cut a hole of circular cross section (geometry), cross-section in solid materials. The drill bit is usually a rotary Cutting tool (machining), cutting tool, often multi-point. The bit is Pressure, pressed against the work-piece and rotated at rates from hundreds to thousands of revolutions per minute. This forces the cutting edge against the work-piece, cutting off Swarf, chips (swarf) from the hole as it is drilled. In Rock (geology), rock drilling, the hole is usually not made through a circular cutting motion, though the bit is usually rotated. Instead, the hole is usually made by hammering a drill bit into the hole with quickly repeated short movements. The hammering action can be performed from outside the hole (top-hammer drill) or within the hole (down-the-hole drill, DTH). Drills used for horizontal drilling are called drifter drills. In rare cases, specially-shaped bits are used to cut holes of non-circular cro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drill Bit
A drill bit is a cutting tool used in a drill to remove material to create holes, almost always of circular cross-section. Drill bits come in many sizes and shapes and can create different kinds of holes in many different materials. In order to create holes drill bits are usually attached to a drill, which powers them to cut through the workpiece, typically by rotation. The drill will grasp the upper end of a bit called the ''shank'' in the chuck. Drills come in standardized drill bit sizes. A comprehensive drill bit and tap size chart lists metric and imperial sized drills alongside the required screw tap sizes. There are also certain specialized drill bits that can create holes with a non-circular cross-section. Characteristics Drill geometry has several characteristics: * The spiral (or rate of twist) in the drill bit controls the rate of chip removal. A fast spiral (high twist rate or "compact flute") drill bit is used in high feed rate applications under low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drill Jig
A drill is a tool used for making round holes or driving fasteners. It is fitted with a drill bit for making holes, or a screwdriver bit for securing fasteners. Historically, they were powered by hand, and later mains power, but cordless battery-powered drills are proliferating due to increased efficiency and ease of use. Drills are commonly used in woodworking, metalworking, construction, machine tool fabrication, and utility projects. Specially designed versions are made for surgery, dentistry, miniatures, and other applications. History Around 35,000 BC, ''Homo sapiens'' discovered the benefits of the application of rotary tools. This would have rudimentarily consisted of a pointed rock being spun between the hands to bore a hole through another material. This led to the hand drill, a smooth stick, that was sometimes attached to flint point, and was rubbed between the palms. This was used by many ancient civilizations around the world including the Mayans. The earli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Residual Stress
In materials science and solid mechanics, residual stresses are stresses that remain in a solid material after the original cause of the stresses has been removed. Residual stress may be desirable or undesirable. For example, laser peening imparts deep beneficial compressive residual stresses into metal components such as turbine engine fan blades, and it is used in toughened glass to allow for large, thin, crack- and scratch-resistant glass displays on smartphones. However, unintended residual stress in a designed structure may cause it to fail prematurely. Residual stresses can result from a variety of mechanisms including inelastic (plastic) deformations, temperature gradients (during thermal cycle) or structural changes ( phase transformation). Heat from welding may cause localized expansion, which is taken up during welding by either the molten metal or the placement of parts being welded. When the finished weldment cools, some areas cool and contract more than others ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drifter Drill
A drifter drill, sometimes called a rock drill, is a tool used in mining and civil engineering to drill into rock (geology), rock. Rock drills are used for making holes for placing dynamite or other explosives in rock blasting, and holes for plug and feather quarrying. While a rock drill may be as simple as a specialized form of chisel, it may also take the form of a powered machine. The mechanism may be worked or powered by hand, by steam, by compressed air (pneumatics), by Hydraulic machinery, hydraulics, or by electricity. Machine rock drills come in two basic forms: those that operate by percussion (using a reciprocating motion), and those that are abrasive (using a rotary motion, rotary motion). A smaller, hand-held percussion rock drill is considered a type of jackhammer. History and types The simplest form of rock drill consists of a long chisel or drill steel that was struck with a sledgehammer. Mark Twain, who worked unsuccessfully as a silver miner in the early 18 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punch (metalworking)
A punch is a tool used to indent or create a hole through a hard surface. They usually consist of a hard metal rod with a narrow tip at one end and a broad flat "butt" at the other. When used, the narrower end is pointed against a target surface and the broad end is struck with a hammer or mallet, causing the blunt force of the blow to be transmitted through the rod body and focused more sharply onto a small area. Typically, woodworkers use a ball-peen hammer to strike a punch. Use Punches are used to drive fasteners such as nail (fastener), nails and dowels, making a hole, or forming an indentation or impression of the tip on a work piece. Decorative punches may also be used to create a pattern or even form an image. Pin Metal pins and similar connectors are driven in or out of holes using a pin punch. For removal, first use a starter punch to loosen the pin, then use a pin punch to finish. Center A ''center punch'' is used to mark the center of a point. It is usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drill Bushing
A drill bushing, also known as a jig bushing, is a tool used in metalworking Jig (tool), jigs to guide cutting tools, most commonly drill bits. Other tools that are commonly used in a drill bushing include counterbores, countersinks, and reamers. They are designed to guide, position, and support the cutting tool.. In the USA, United States customary units, Customary sized bushings are standardized via ASME B94.33 and Metric system, metric bushings are standardized via ASME B94.33.1.. There are over 50,000 standard configurations of customary sized bushings. Types Drill bushings can generally be classified as: ''press fit'' bushings or ''renewable'' bushings. Other classification methods include by head type, by use, and by liner type (or lack thereof). Press-fit bushings Press fit are available in two types with liners or without (''wearing'' bushings). Liner bushings, sometimes called ''master bushings'', are permanently installed into the jig and accept liners that can easily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutting Fluid
Cutting fluid is a type of coolant and lubricant designed specifically for metalworking processes, such as machining and stamping. There are various kinds of cutting fluids, which include oils, oil-water emulsions, pastes, gels, aerosols (mists), and air or other gases. Cutting fluids are made from petroleum distillates, animal fats, plant oils, water and air, or other raw ingredients. Depending on context and on which type of cutting fluid is being considered, it may be referred to as cutting fluid, cutting oil, cutting compound, coolant, or lubricant. Most metalworking and machining processes can benefit from the use of cutting fluid, depending on workpiece material. Common exceptions to this are cast iron and brass, which may be machined dry (though this is not true of all brasses, and any machining of brass will likely benefit from the presence of a cutting fluid). The properties that are sought after in a good cutting fluid are the ability to: * Keep the workpiece at a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutting
Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force. Implements commonly used for wikt:cut, cutting are the knife and saw, or in medicine and science the scalpel and microtome. However, any sufficiently sharp object is capable of cutting if it has a hardness sufficiently larger than the object being cut, and if it is applied with sufficient force. Even liquids can be used to cut things when applied with sufficient force (see water jet cutter). Cutting is a compression (physical), compressive and shearing (physics), shearing phenomenon, and occurs only when the total stress (physics), stress generated by the cutting implement exceeds the ultimate Strength of materials, strength of the material of the object being cut. The simplest applicable equation is: :\text = or \tau=\frac The stress generated by a cutting implement is directly proportional to the force with which it is applied, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burr (metal)
A burr is a raised edge or small piece of material that remains attached to a workpiece after a modification process. It is usually an unwanted piece of material and is removed with a deburring tool in a process called deburring. Burrs are most commonly created by machining operations, such as grinding, drilling, milling, engraving or turning. It may be present in the form of a fine wire on the edge of a freshly sharpened tool or as a raised portion of a surface; this type of burr is commonly formed when a hammer strikes a surface. Deburring accounts for a significant portion of manufacturing costs. In the printmaking technique of drypoint, burr, which gives a rich fuzzy quality to the engraved line, is highly desirable—the great problem with the drypoint medium is that the burr rapidly diminishes after as few as ten impressions are printed. Types There are three types of burrs that can be formed from machining operations: ''Poisson burr'', ''rollover burr'', and ''breakout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stress (mechanics)
In continuum mechanics, stress is a physical quantity that describes forces present during deformation. For example, an object being pulled apart, such as a stretched elastic band, is subject to ''tensile'' stress and may undergo elongation. An object being pushed together, such as a crumpled sponge, is subject to ''compressive'' stress and may undergo shortening. The greater the force and the smaller the cross-sectional area of the body on which it acts, the greater the stress. Stress has dimension of force per area, with SI units of newtons per square meter (N/m2) or pascal (Pa). Stress expresses the internal forces that neighbouring particles of a continuous material exert on each other, while ''strain'' is the measure of the relative deformation of the material. For example, when a solid vertical bar is supporting an overhead weight, each particle in the bar pushes on the particles immediately below it. When a liquid is in a closed container under pressure, each ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
