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Decambering is the metalworking process of removing camber, or horizontal bend, from strip shaped materials. The material may be finite length sections or continuous coils. Decambering resembles flattening or levelling processes, but deforms the material edge (left or right) instead of the face (up or down) of the strip.
Decambering may be accomplished by a choice of several processes:
The material may be "stretchformed" or stretched typically 1-2% elongation past its elastic limit, such that the camber is strained out, and the strip relaxes straight. Typically this is accomplished by routing the strip through two sets of 180 degree or more wrap driven "bridle rolls" with the second rolls rotating faster than the first. Cut strip can be gripped each end then stretched on a static rig with one end being mechanically pulled. The "stretchforming" process is most suited to thin strip.
Wider material can be flat rolled with the rolls tilting such that the "short" edge is lengthened, with thickness slightly reduced, to equal the "long" edge. The material is then straight if properly processed. Several different types of these machines are available, ranging from position controlled to pressure controlled machines. Also, machines are available with automatic self checking features. If the material has residual stress as in toothed bandsaw blades, the rolls must not uniformly apply cross strain, as the inherent strain will distort the strip. In these cases, rolls exert corrective strain in a linear narrow strip inboard of the edge each side. In the case of sawblades with teeth on, the corrective squeezed strip on the toothed edge is located along the tooth gullet, and corrective squeeze on the toothed side must be about 2.5 times the corrective force on the plain edge.
If the strip is narrow and thick enough, side rolls with guide grooves can be used to bend the material laterally to remove the camber. There are many patented designs of these machines, with the best engaging the material on both edges of the strip over the worked portion, preventing the material from twisting or "cheating" the corrective lateral bending.
Note that camber is often caused by slitting, where slitting knives extend the edge being slit. Outer edges left untreated usually have a shorter length than the inner edges being formed by slitting. The outer mults from slitting will therefore usually have camber, while inner mults frequently will not. Decamberers are cost effective when material is not laterally straight enough to suit a given process, and needs upgrading. Cambered material is usually lower in cost than straight material, and decamberers offer savings in these cases. Various types of decambering machines cater to wide or narrow materials.
A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Substantially longer than they are wide, and characteristically employed in pairs, skis are attached to ski boots with ski bindings, with either a free, lockable, or partially secured heel. For climbing slopes, ski skins can be attached at the base of the ski.
The router is a power tool with a flat base and a rotating blade extending past the base. The spindle may be driven by an electric motor or by a pneumatic motor. It routs an area in hard material, such as wood or plastic. Routers are used most often in woodworking, especially cabinetry. They may be handheld or affixed to router tables. Some woodworkers consider the router one of the most versatile power tools.
A saw is a tool consisting of a tough blade, wire, or chain with a hard toothed edge. It is used to cut through material, very often wood, though sometimes metal or stone. The cut is made by placing the toothed edge against the material and moving it back and forth, or continuously forward. This force may be applied by hand, or powered by steam, water, electricity or other power source. An abrasive saw has a powered circular blade designed to cut through metal or ceramic.
A perforation is a small hole in a thin material or web. There is usually more than one perforation in an organized fashion, where all of the holes collectively are called a perforation. The process of creating perforations is called perforating, which involves puncturing the workpiece with a tool.
A leaf spring is a simple form of spring commonly used for suspension in wheeled vehicles. Originally called a laminated or carriage spring, and sometimes referred to as a semi-elliptical spring, elliptical spring, or cart spring, it is one of the oldest forms of vehicle suspension. A leaf spring is one or more narrow, arc-shaped, thin plates that are attached to the axle and chassis in a way that allows the leaf spring to flex vertically in response to irregularities in the road surface. Lateral leaf springs are the most commonly used arrangement, running the length of the vehicle and mounted perpendicular to the wheel axle, but numerous examples of transverse leaf springs exist as well.
A die is a specialized machine tool used in manufacturing industries to cut and/or form material to a desired shape or profile. Stamping dies are used with a press, as opposed to drawing dies and casting dies which are not. Like molds, dies are generally customized to the item they are used to create.
Rotogravure is a type of intaglio printing process, which involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a cylinder because, like offset printing and flexography, it uses a rotary printing press.
A bandsaw is a power saw with a long, sharp blade consisting of a continuous band of toothed metal stretched between two or more wheels to cut material. They are used principally in woodworking, metalworking, and lumbering, but may cut a variety of materials. Advantages include uniform cutting action as a result of an evenly distributed tooth load, and the ability to cut irregular or curved shapes like a jigsaw. The minimum radius of a curve is determined by the width of the band and its kerf. Most bandsaws have two wheels rotating in the same plane, one of which is powered, although some may have three or four to distribute the load. The blade itself can come in a variety of sizes and tooth pitches, which enables the machine to be highly versatile and able to cut a wide variety of materials including wood, metal and plastic.
Sheet metal is metal formed into thin, flat pieces, usually by an industrial process. Sheet metal is one of the fundamental forms used in metalworking, and it can be cut and bent into a variety of shapes.
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.
Siping is a process of cutting thin slits across a rubber surface to improve traction in wet or icy conditions.
In metalworking, rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness, to make the thickness uniform, and/or to impart a desired mechanical property. The concept is similar to the rolling of dough. Rolling is classified according to the temperature of the metal rolled. If the temperature of the metal is above its recrystallization temperature, then the process is known as hot rolling. If the temperature of the metal is below its recrystallization temperature, the process is known as cold rolling. In terms of usage, hot rolling processes more tonnage than any other manufacturing process, and cold rolling processes the most tonnage out of all cold working processes. Roll stands holding pairs of rolls are grouped together into rolling mills that can quickly process metal, typically steel, into products such as structural steel, bar stock, and rails. Most steel mills have rolling mill divisions that convert the semi-finished casting products into finished products.
A burr is a raised edge or small piece of material that remains attached to a workpiece after a modification process.
Converting companies are companies that specialize in modifying or combining raw materials such as polyesters, adhesives, silicone, adhesive tapes, foams, plastics, felts, rubbers, liners and metals, as well as other materials, to create new products.
In metallurgy, cold forming or cold working is any metalworking process in which metal is shaped below its recrystallization temperature, usually at the ambient temperature. Such processes are contrasted with hot working techniques like hot rolling, forging, welding, etc. The same or similar terms are used in glassmaking for the equivalents; for example cut glass is made by "cold work", cutting or grinding a formed object.
Roll slitting is a shearing operation that cuts a large roll of material into narrower rolls. There are two types of slitting: log slitting and rewind slitting. In log slitting the roll of material is treated as a whole and one or more slices are taken from it without an unrolling/re-reeling process. In rewind slitting the web is unwound and run through the machine, passing through knives or lasers, before being rewound on one or more shafts to form narrower rolls. The multiple narrower strips of material may be known as mults or pancakes if their diameter is much more than their width. For rewind slitting the machine used is called a slitter rewinder, a slitter or a slitting machine – these names are used interchangeably for the same machines. For particularly narrow and thin products, the pancakes become unstable, and then the rewind may be onto a bobbin-wound reel: the rewind bobbins are much wider than the slit width and the web oscillates across the reel as it is rewound. Apart from the stability benefit it is also then possible to put very long lengths,, onto one bobbin.
Rings, slides and hooks are the accessories used in intimate apparel/lingerie used for adjustment and decorative functions. Rings, slides and hooks are commonly made of plastic and nylon coated metal and stainless steel.
Marstonia comalensis is a species of minute freshwater snail with a gill and an operculum, an aquatic gastropod mollusk or micromollusk in the family Hydrobiidae. It is found in south central Texas, United States.
The splitting band knife is a kind of knife used in several fields including: tannery, EVA/rubber, foam, cork, shoe and leather goods, paper, carpet and other soft sheet materials. It is a power tool which is very similar in operation to a band saw, with an endless loop blade; the material to be cut is supported by a flat table.
A tandem rolling mill is a rolling mill with two or more close-coupled stands, where the reduction is achieved by the inter-stand tension(s) and the compressive force between the work rolls.
"Decamberer Maintains Lock Bar Straightness" by J. Neiland Pennington, Senior Editor, Modern Metals magazine pp 26–28, July 1997, Trend Publishing, Inc. Chicago, Il 60611–3110.
US patent US6038904 "Decamberer" 2000-03-21, Barnes, Austen
US patent US5904058 "Decamberer" 1999-05-18 Barnes, Austen
German patent DE19857278 "Camber correction for wide strip in rolling mill using pneumatic cylinder actuators to control pressure applied by rolls" 2000-06-21 Barnes, Austen Bernard