Bar stock , also (colloquially) known as blank , slug or billet , is a common form from metal refined purification, is used by industries to produce metal components and products. Stem stocks are available in various shapes and lengths of extrusion. The most common forms are circular (cross-section), rectangular, square and hexagonal or hex. A bar is marked with a "closed-seated convex cross section", meaning that pipes, stock angles and objects of varying diameter are not considered stem stocks.
Bar stock is usually processed by a sequence of sawing, twisting, milling, drilling and grinding to produce the final product, often very different from the original stock. In some cases, this process is partially automated by specialized equipment that supplies stock to the appropriate processing machine.
Video Bar stock
Process and type
Most of the metal produced by steel mills or aluminum plants is formed (through rolling or extrusion) into long continuous strips of various sizes and shapes. These strips are cut regularly and left to cool, each segment being part of the stock bar. A good analogy is the making of a paste, in which the dough lump is extruded into various cross sectional forms; cut long; and then dried in that form. Cross-sectional paste shapes range from simple bar or tube shapes (such as linguine or penne) to more sophisticated extrusions (such as rotelle, fiori, or rotini). The same applies to stocks of metal bars. The most common forms are round bars (also called sticks ), rectangular bars (including the square bar , specifically case of equal sides), and a hexagonal bar (usually called hex bar for short). Tubes and pipes are similar, but have hollow centers and are traditionally not called "bars" in industrial use. (However, a product called a hollow bar, basically a tube but with a customizable OD and ID and thus a special wall thickness, is marketed for a lathe work that can benefit from drilling and drudgery boring obstruction.) Also similar in concept, but not called "bars", are common structural forms such as corner stock and channel stock. These are usually available in steel and aluminum; the names "iron elbows" and "ductile iron" are still frequently used (informally) even though their literal namesake, wrought iron, has been replaced by steel and aluminum for most uses.
In a machine shop, stock and bar plates are often called billet , although in a rolling mill, the word refers to a piece of unbound metal to the bar.
Machine shops usually have storage areas that contain a variety of stock bars. To create metal components, sufficient volume bars are selected from storage and taken to the machining area. This piece can then be sawed, milled, drilled, rotated, or ground to remove the material and make the final shape. When rotating, for large-diameter work (typically over 100 millimeters (3.9 inches), though there is no universal threshold), cut pieces are cut using horizontal bandsaw to make blank for each section. The empty part is then inserted into the chucker of each chucker alternately. For smaller-diameter jobs, the entire length of the stock bar is more often inserted through the lathe spindle. The entire rod rotates with the axis during the machining-part cycle. When the cycle ends and one part is completed, the chuck is open, the bar is pulled or pushed forward ("fed") by various automatic means, the chuck closes, and the next cycle begins. The last step of this cycle is cutting the engine part of the bar, called "splitting it" and achieved by a "cutoff" or "part-off" tool, the bit tool that lines the bars all the way to the midline, causing the falling part. Then the cycle repeats itself.
Uncut stems protruding from the back of the spindle, spinning rapidly, may pose a safety hazard if they are too far away and not to be knocked out of bending. So sometimes bar long should be sawed into short bars before being fed as "work bar" (which is the term for the job).
The CNC lathe and screw machine have accessories called "feed bar", which hold, guide, and feed the bar as instructed by CNC control. More sophisticated machines may have a "bar loader" that holds several bars and feeds them one by one to the feeder bar. Bar loaders are like magazines for empty sections (or palettes for milling jobs) because they allow light machining. Loader bar is filled with bars (or magazines or pallets with blanks) during working hours, and then runs during the night unattended. Given that there are no humans around to detect if anything is wrong and the machine must stop, there are different types of sensors used to detect these, such as meter loads, infrared rays, and, in recent years, a webcam, housed inside a tool enclosure engine and allowing a view away from the act of cutting.
Maps Bar stock
Standard size across the supply chain
To store any possible stock bar size (any possible fraction of a millimeter or inch in diameter or thickness) is impossible. Thus, stock bars are stocked by metal supply houses in various standard sizes, arranged in separate steps. For example, a round bar with a millimeter diameter even (or in the United States, on eighths of an inch) can usually be ordered from standing stock. Non-standard size diameter bars can also be obtained, but only as separate factories run from the rolling mill. So they are much more expensive than standard sizes, can take longer delivery time, and are not desirable as inventory for home supplies or machine shop (because of the possibility of selling or using certain special sizes are very thin).
Sometimes it is necessary that the bar will not be much larger than the intended part, because the metallurgical properties of some metal alloys in some finishing process can vary with how far inside the bars lies metal. So the engineering drawing will determine the specific size (or maximum size) that the bar can start as. This specification faces restrictions on the size of the previously mentioned stock versus custom factory operations; standard measures are used wherever possible to avoid wasted costs and unnecessary delays.
Drill bit
A drill bit is a rounded steel stocking tool to the ground with a tight tolerance diameter; usually  ± 0.0005Ã, in (Ã,  ± 0.0127 mm). In England the name "silver steel" is often identical and sometimes hyponymous. Its origin is a reference to the appearance of glossy earth (not for silver alloy content). Drill bar diameter ranges from 0.0135 to 1.5Ã, in (0.34 to 38.10 mm); in the United States a diameter smaller than / 64 of an inch is made in drill size letters and drill size numbers, in addition to fractional sizes. The length is usually one or three feet (0.3 or 0.9 m). These are usually used to make drill bits, taps, reamers, punches, dowel pins, and shafts. Note that the numbered sizes are different from the drill size starting at 52. This measure is:
The empty drill has a tolerance measuring less than 0/-0.0002 inside, while the empty reamer has a oversize tolerance of -0/0.0002 at.
Some factories also sell square stocks held with the same tolerances as the "drillsticks".
The commonly available material values ​​in the US are A2, D2, M2, M42, O1, S7, W1, and high speed steels (including M2/M7).
Soil flat stock
flat ground stock is annealed milled annealed to close tolerance (compare with drill bars). There are four types of materials available: O-1 tool steel, A-2 tool steel, A-6 tool steel, and 1018 steel (low carbon or low-carb steel). The length is 18 or 36 in (457 or 914 mm) in length, widths of up to 16 in (406 mm) are available, and thickness ranges from 1 / 64 to 2.875 at (0.40 to 73.03 mm).
Some geometric sizes are known as gauge .
References
Source of the article : Wikipedia
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