Misplaced Pages

#105894

57-521: East Cambridgeshire (locally known as East Cambs ) is a local government district in Cambridgeshire , England. Its council is based in the city of Ely . The district also contains the towns of Littleport and Soham and surrounding rural areas, including parts of the Fens . Since 2017 the district has been a constituent member of the Cambridgeshire and Peterborough Combined Authority , led by

114-420: A YAG based laser with a wavelength of around 1 μm. Photochemical machining, also known as photo etching, is a tightly controlled corrosion process which is used to produce complex metal parts from sheet metal with very fine detail. The photo etching process involves photo sensitive polymer being applied to a raw metal sheet. Using CAD designed photo-tools as stencils, the metal is exposed to UV light to leave

171-416: A class of structural steel . Sheet metal is available in flat pieces or coiled strips. The coils are formed by running a continuous sheet of metal through a roll slitter . In most of the world, sheet metal thickness is consistently specified in millimeters. In the U.S., the thickness of sheet metal is commonly specified by a traditional, non-linear measure known as its gauge . The larger the gauge number,

228-459: A color-coated metal sheet. Sheet metal is used in automobile and truck (lorry) bodies , major appliances , airplane fuselages and wings , tinplate for tin cans , roofing for buildings (architecture), and many other applications. Sheet metal of iron and other materials with high magnetic permeability , also known as laminated steel cores , has applications in transformers and electric machines . Historically, an important use of sheet metal

285-431: A design pattern, which is developed and etched from the metal sheet. Perforating is a cutting process that punches multiple small holes close together in a flat workpiece. Perforated sheet metal is used to make a wide variety of surface cutting tools, such as the surform . This is a form of bending used to produce long, thin sheet metal parts. The machine that bends the metal is called a press brake . The lower part of

342-473: A laser for cutting compound shapes, but faster for repetitive shapes (for example, the grille of an air-conditioning unit). A CNC punch can achieve 600 strokes per minute. A typical component (such as the side of a computer case) can be cut to high precision from a blank sheet in under 15 seconds by either a press or a laser CNC machine. A continuous bending operation for producing open profiles or welded tubes with long lengths or in large quantities. Rolling

399-549: A punch and a die mounted in a press. The punch and die are made of hardened steel and are the same shape. The punch is sized to be a very close fit in the die. The press pushes the punch against and into the die with enough force to cut a hole in the stock. In some cases the punch and die "nest" together to create a depression in the stock. In progressive stamping , a coil of stock is fed into a long die/punch set with many stages. Multiple simple shaped holes may be produced in one stage, but complex holes are created in multiple stages. In

456-490: A series of processes in which small incremental deformation can be done in each series. Ironing is a sheet metal working or sheet metal forming process. It uniformly thins the workpiece in a specific area. This is a very useful process. It is used to produce a uniform wall thickness part with a high height-to-diameter ratio. It is used in making aluminium beverage cans. Sheet metal can be cut in various ways, from hand tools called tin snips up to very large powered shears. With

513-552: A square/circle and welding the seam together. Their wall thickness has a similar (but distinct) gauge to the thickness of steel sheets. During the rolling process the rollers bow slightly, which results in the sheets being thinner on the edges. The tolerances in the table and attachments reflect current manufacturing practices and commercial standards and are not representative of the Manufacturer's Standard Gauge, which has no inherent tolerances. The equation for estimating

570-576: A two-tier arrangement. Non-metropolitan districts with borough status are known as boroughs , able to appoint a mayor and refer to itself as a borough council. Some shire counties now have no sub divisions so are a single Non-metropolitan district such as Cornwall. Typically a district will consist of a market town and its more rural hinterland. However districts are diverse with some being mostly urban such as Dartford, and others more polycentric such as Thurrock. Non-metropolitan districts are subdivisions of English non-metropolitan counties which have

627-461: A two-tier structure of local government. Two-tier non-metropolitan counties have a county council and several districts, each with a borough or district council. In these cases local government functions are divided between county and district councils, to the level where they can be practised most efficiently: Many districts have borough status , which means the local council is called a borough council instead of district council and gives them

SECTION 10

#1732786596106

684-408: A unitary authority or those that transferred from one county to another, including those that changed name. Nor does it include unitary authorities that have been abolished ( Bournemouth and Poole ). Metal sheet Thicknesses can vary significantly; extremely thin sheets are considered foil or leaf , and pieces thicker than 6 mm (0.25 in) are considered plate, such as plate steel,

741-400: Is a heat treatable stainless steel, but it has a lower corrosion resistance than the other grades. It is commonly used in cutlery . The only available finish is dull. Grade 430 is a popular grade, low-cost alternative to series 300's grades. This is used when high corrosion resistance is not a primary criterion. Common grade for appliance products, often with a brushed finish. Aluminium

798-477: Is a common heat-treated structural aluminium alloy. It is weldable, corrosion resistant, and stronger than 5052, but not as formable. It loses some of its strength when welded. It is used in modern aircraft structures. Brass is an alloy of copper, which is widely used as a sheet metal. It has more strength, corrosion resistance and formability when compared to copper while retaining its conductivity. In sheet hydroforming, variation in incoming sheet coil properties

855-567: Is a common problem for forming process, especially with materials for automotive applications. Even though incoming sheet coil may meet tensile test specifications, high rejection rate is often observed in production due to inconsistent material behavior. Thus there is a strong need for a discriminating method for testing incoming sheet material formability. The hydraulic sheet bulge test emulates biaxial deformation conditions commonly seen in production operations. For forming limit curves of materials aluminium, mild steel and brass. Theoretical analysis

912-468: Is a process of cutting or stamping slits in alternating pattern much like the stretcher bond in brickwork and then stretching the sheet open in accordion-like fashion. It is used in applications where air and water flow are desired as well as when light weight is desired at cost of a solid flat surface. A similar process is used in other materials such as paper to create a low cost packing paper with better supportive properties than flat paper alone. Hemming

969-404: Is a process of folding the edge of sheet metal onto itself to reinforce that edge. Seaming is a process of folding two sheets of metal together to form a joint. Hydroforming is a process that is analogous to deep drawing, in that the part is formed by stretching the blank over a stationary die . The force required is generated by the direct application of extremely high hydrostatic pressure to

1026-445: Is also utilized as a catalyst ). These metal sheets are processed through different processing technologies, mainly including cold rolling and hot rolling . Sometimes hot-dip galvanizing process is adopted as needed to prevent it from rusting due to constant exposure to the outdoors. Sometimes a layer of color coating is applied to the surface of the cold-rolled sheet to obtain a decorative and protective metal sheet, generally called

1083-490: Is carried out by deriving governing equations for determining of equivalent stress and equivalent strain based on the bulging to be spherical and Tresca's yield criterion with the associated flow rule. For experimentation circular grid analysis is one of the most effective methods. Use of gauge numbers to designate sheet metal thickness is discouraged by numerous international standards organizations. For example, ASTM states in specification ASTM A480-10a: "The use of gauge number

1140-402: Is clear in column 3 (U.S. standard for sheet and plate iron and steel 64ths inch (delta)). The thicknesses vary first by 1 ⁄ 32 inch in higher thicknesses and then step down to increments of 1 ⁄ 64 inch, then 1 ⁄ 128 inch, with the final increments at decimal fractions of 1 ⁄ 64 inch. Some steel tubes are manufactured by folding a single steel sheet into

1197-569: Is commonly used in chemical processing equipment, light reflectors, and jewelry . Grade 3003-H14 is stronger than 1100, while maintaining the same formability and low cost. It is corrosion resistant and weldable. It is often used in stampings , spun and drawn parts, mail boxes , cabinets , tanks , and fan blades. Grade 5052-H32 is much stronger than 3003 while still maintaining good formability. It maintains high corrosion resistance and weldability. Common applications include electronic chassis, tanks, and pressure vessels . Grade 6061-T6

SECTION 20

#1732786596106

1254-566: Is discouraged as being an archaic term of limited usefulness not having general agreement on meaning." Manufacturers' Standard Gauge for Sheet Steel is based on an average density of 41.82 lb per square foot per inch thick, equivalent to 501.84 pounds per cubic foot (8,038.7 kg/m ). Gauge is defined differently for ferrous (iron-based) and non-ferrous metals (e.g. aluminium and brass). The gauge thicknesses shown in column 2 (U.S. standard sheet and plate iron and steel decimal inch (mm)) seem somewhat arbitrary. The progression of thicknesses

1311-569: Is divided into civil parishes . The parish of Ely holds city status , and the parish councils for Soham and Littleport take the style "town council". 52°23′13″N 0°17′38″E  /  52.387°N 0.294°E  / 52.387; 0.294 Non-metropolitan district Non-metropolitan districts , or colloquially " shire districts ", are a type of local government district in England. As created, they are sub-divisions of non-metropolitan counties (colloquially shire counties ) in

1368-452: Is generally done in multiple steps called draw reductions. The greater the depth, the more reductions are required. Deep drawing may also be accomplished with fewer reductions by heating the workpiece, for example in sink manufacture. In many cases, material is rolled at the mill in both directions to aid in deep drawing. This leads to a more uniform grain structure which limits tearing and is referred to as "draw quality" material. Expanding

1425-422: Is heated and burnt by the laser beam, cutting the metal sheet. The quality of the edge can be mirror smooth and a precision of around 0.1 mm (0.0039 in) can be obtained. Cutting speeds on thin 1.2 mm (0.047 in) sheet can be as high as 25 m (82 ft) per minute. Most laser cutting systems use a CO 2 based laser source with a wavelength of around 10  μm ; some more recent systems use

1482-423: Is metal working or metal forming process. In this method, stock passes through one or more pair of rolls to reduce thickness. It is used to make thickness uniform. It is classified according to its temperature of rolling: Spinning is used to make tubular (axis-symmetric) parts by fixing a piece of sheet stock to a rotating form ( mandrel ). Rollers or rigid tools press the stock against the form, stretching it until

1539-435: Is the open width of a V-die or wiping die. The curling process is used to form an edge on a ring. This process is used to remove sharp edges. It also increases the moment of inertia near the curled end. The flare/burr should be turned away from the die. It is used to curl a material of specific thickness. Tool steel is generally used due to the amount of wear done by operation. It is a metal working process of removing camber,

1596-403: Is widely used in sheet metal form due to its flexibility, wide range of options, cost effectiveness, and other properties. The four most common aluminium grades available as sheet metal are 1100-H14, 3003-H14, 5052-H32, and 6061-T6. Grade 1100-H14 is commercially pure aluminium, highly chemical and weather resistant. It is ductile enough for deep drawing and weldable, but has low strength. It

1653-493: The Conservatives with exactly half the council's seats. They continue to form the council's administration by virtue of holding the chair's casting vote. The first election to the council was held in 1973, initially operating as a shadow authority alongside the outgoing authorities until the new arrangements came into effect on 1 April 1974. Political control of the council since 1974 has been as follows: The leaders of

1710-604: The District Councils' Network , special interest group which sits within the Local Government Association . The network's purpose is to "act as an informed and representative advocate for districts to government and other national bodies, based on their unique position to deliver for local people." This is a list of two-tier non-metropolitan counties and their districts. All unitary authorities are also non-metropolitan districts, which, with

1767-451: The 1870s, being used for shingle roofing, stamped ornamental ceilings, and exterior façades. Sheet metal ceilings were only popularly known as " tin ceilings " later as manufacturers of the period did not use the term. The popularity of both shingles and ceilings encouraged widespread production. With further advances of steel sheet metal production in the 1890s, the promise of being cheap, durable, easy to install, lightweight and fireproof gave

East Cambridgeshire - Misplaced Pages Continue

1824-674: The Moyse's Hall Museum in Bury St Edmunds while other items are in the University of Cambridge Museum of Archaeology and Anthropology in Cambridge . Other finds include traces of cremations and barrows , golden torques , an extensive ditch system and a wooden track-way between Fordey Farm (Barway) and Little Thetford . Bronze razors have also been found and it is well known that Celts shaved their cheeks. The whole district

1881-428: The advances in technology, sheet metal cutting has turned to computers for precise cutting. Many sheet metal cutting operations are based on computer numerically controlled (CNC) laser cutting or multi-tool CNC punch press. CNC laser involves moving a lens assembly carrying a beam of laser light over the surface of the metal. Oxygen, nitrogen or air is fed through the same nozzle from which the laser beam exits. The metal

1938-454: The areas for Wales and England had been enacted separately and there were no Welsh metropolitan areas, the term 'non-metropolitan district' does not apply to Wales. A similar system existed in Scotland , which in 1975 was divided into regions and districts, this was also abolished in 1996 and replaced with a fully unitary system . In England most of the district councils are represented by

1995-429: The backstop, more advanced machines control the position and angle of the stop, its height and the position of the two reference pegs used to locate the material. The machine can also record the exact position and pressure required for each bending operation to allow the operator to achieve a perfect 90 degree bend across a variety of operations on the part. Punching is performed by placing the sheet of metal stock between

2052-596: The council since 2011 have been: Following the 2023 election and a by-election in April 2024 and change of allegiance in August 2024, the composition of the council was: The next election is due in 2027. Since the last full review of boundaries in 2019 the council has comprised 28 councillors , representing 14 wards . Elections are held every four years. The council is based at The Grange on Nutholt Lane in Ely. The building

2109-477: The directly elected Mayor of Cambridgeshire and Peterborough . The neighbouring districts are South Cambridgeshire , Huntingdonshire , Fenland , King's Lynn and West Norfolk and West Suffolk . The district was formed on 1 April 1974 under the Local Government Act 1972 . The new district covered the area of three former districts, which were all abolished at the same time: The new district

2166-487: The exception of those of Berkshire , are coterminous with non-metropolitan counties. For a full list of districts of all types including unitary authorities, metropolitan districts and London boroughs , see Districts of England . This is a list of former two-tier districts in England which have been abolished, by local government reorganisations such as the 2009 structural changes to local government in England . It does not include districts that still exist after becoming

2223-401: The final stage, the part is punched free from the "web". A typical CNC turret punch has a choice of up to 60 tools in a "turret" that can be rotated to bring any tool to the punching position. A simple shape (e.g. a square, circle, or hexagon) is cut directly from the sheet. A complex shape can be cut out by making many square or rounded cuts around the perimeter. A punch is less flexible than

2280-453: The horizontal bend, from a strip shaped material. It may be done to a finite length section or coils. It resembles flattening of leveling process, but on a deformed edge. Drawing is a forming process in which the metal is stretched over a form or die . In deep drawing the depth of the part being made is more than half its diameter. Deep drawing is used for making automotive fuel tanks, kitchen sinks, two-piece aluminum cans , etc. Deep drawing

2337-476: The manual process in the late 17th century. The process of flattening metal sheets required large rotating iron cylinders which pressed metal pieces into sheets. The metals suited for this were lead, copper, zinc, iron and later steel. Tin was often used to coat iron and steel sheets to prevent it from rusting. This tin-coated sheet metal was called " tinplate ." Sheet metals appeared in the United States in

East Cambridgeshire - Misplaced Pages Continue

2394-410: The maximum bending force is, F max = k T L t 2 W {\displaystyle F_{\text{max}}=k{\frac {TLt^{2}}{W}}} , where k is a factor taking into account several parameters including friction. T is the ultimate tensile strength of the metal. L and t are the length and thickness of the sheet metal, respectively. The variable W

2451-411: The metal down the required amount to bend it through 90 degrees. Typically, a general purpose machine has an available bending force of around 25 tons per meter of length. The opening width of the lower die is typically 8 to 10 times the thickness of the metal to be bent (for example, 5 mm material could be bent in a 40 mm die). The inner radius of the bend formed in the metal is determined not by

2508-401: The middle-class a significant appetite for sheet metal products. It was not until the 1930s and WWII that metals became scarce and the sheet metal industry began to collapse. However, some American companies, such as the W.F. Norman Corporation, were able to stay in business by making other products until Historic preservation projects aided the revival of ornamental sheet metal. Grade 304 is

2565-445: The most common of the three grades. It offers good corrosion resistance while maintaining formability and weldability . Available finishes are #2B, #3, and #4. Grade 303 is not available in sheet form. Grade 316 possesses more corrosion resistance and strength at elevated temperatures than 304. It is commonly used for pumps , valves , chemical equipment, and marine applications. Available finishes are #2B, #3, and #4. Grade 410

2622-428: The press contains a V-shaped groove called the die. The upper part of the press contains a punch that presses the sheet metal down into the v-shaped die, causing it to bend. There are several techniques used, but the most common modern method is "air bending". Here, the die has a sharper angle than the required bend (typically 85 degrees for a 90 degree bend) and the upper tool is precisely controlled in its stroke to push

2679-464: The radius of the upper tool, but by the lower die width. Typically, the inner radius is equal to 1/6 of the V-width used in the forming process. The press usually has some sort of back gauge to position depth of the bend along the workpiece. The backgauge can be computer controlled to allow the operator to make a series of bends in a component to a high degree of accuracy. Simple machines control only

2736-1025: The region to the north of Devil's Dyke and Cambridge , from the Stone Age , the Bronze Age and the Iron Age (the region south of Devil's Dyke is not yet included in the survey). By far the greatest quantities of bronze objects found in England were discovered in East Cambridgeshire. The most important Bronze Age finds were discovered in Isleham (more than 6500 pieces), Stuntney , Soham , Wicken , Chippenham , Coveney , Mepal and Wilburton . These findings include swords , spear -heads, arrows , axes , palstaves , knives , daggers , rapiers , armour , decorative equipment (in particular for horses) and many fragments of sheet bronze . The greater part of these objects have been entrusted to

2793-565: The right to appoint a mayor . Borough status is granted by royal charter and, in many cases, continues a style enjoyed by a predecessor authority, which can date back centuries. Some districts such as Oxford or Exeter have city status , granted by letters patent , but this does not give the local council any extra powers other than the right to call itself a city council . By 1899, England had been divided at district level into rural districts , urban districts , municipal boroughs , county boroughs and metropolitan boroughs . This system

2850-412: The stock takes the shape of the form. Spinning is used to make rocket motor casings, missile nose cones, satellite dishes and metal kitchen funnels. Stamping includes a variety of operations such as punching, blanking, embossing, bending, flanging, and coining; simple or complex shapes can be formed at high production rates; tooling and equipment costs can be high, but labor costs are low. Alternatively,

2907-676: The thinner the metal. Commonly used steel sheet metal ranges from 30 gauge to about 7 gauge. Gauge differs between ferrous ( iron-based ) metals and nonferrous metals such as aluminum or copper. Copper thickness, for example, is measured in ounces, representing the weight of copper contained in an area of one square foot. Parts manufactured from sheet metal must maintain a uniform thickness for ideal results. There are many different metals that can be made into sheet metal, such as aluminium , brass , copper , steel , tin , nickel and titanium . For decorative uses, some important sheet metals include silver , gold , and platinum (platinum sheet metal

SECTION 50

#1732786596106

2964-526: The two-tier structure, but reforms in the 1990s and 2009 reduced their number to 192. A further 55 non-metropolitan districts are now unitary authorities, which combine the functions of county and borough/district councils. In Wales , an almost identical two-tier system of local government existed between 1974 and 1996 (see Districts of Wales ). In 1996, this was abolished and replaced with an entirely unitary system of local government, with one level of local government responsible for all local services. Since

3021-424: The workpiece or to a bladder that is in contact with the workpiece, rather than by the movable part of a die in a mechanical or hydraulic press. Unlike deep drawing, hydroforming usually does not involve draw reductions—the piece is formed in a single step. Incremental sheet forming or ISF forming process is basically sheet metal working or sheet metal forming process. In this case, sheet is formed into final shape by

3078-620: Was abolished by the London Government Act 1963 and the Local Government Act 1972 . Non-metropolitan districts were created by this act in 1974 when England outside Greater London was divided into metropolitan counties and non-metropolitan counties. Metropolitan counties were sub-divided into metropolitan districts and the non-metropolitan counties were sub-divided into non-metropolitan districts. The metropolitan districts had more powers than their non-metropolitan counterparts. Initially, there were 296 non-metropolitan districts in

3135-401: Was in plate armor worn by cavalry , and sheet metal continues to have many decorative uses, including in horse tack . Sheet metal workers are also known as "tin bashers" (or "tin knockers"), a name derived from the hammering of panel seams when installing tin roofs. Hand-hammered metal sheets have been used since ancient times for architectural purposes. Water-powered rolling mills replaced

3192-434: Was named East Cambridgeshire, reflecting its position within the wider county. East Cambridgeshire District Council provides district-level services. County-level services are provided by Cambridgeshire County Council . The whole district is also covered by civil parishes , which form a third tier of local government. The council has been under no overall control since a change in allegiance in August 2024, which left

3249-401: Was originally a large Victorian house. It served as a maternity hospital from the 1940s until the 1970s. The building was acquired around the time East Cambridgeshire was created in 1974 and converted to offices. Several large extensions have since been added. The Fenland Survey of archaeological finds carried out in the 1980s mentions an enumeration of findings made between 1884 and 1994 in

#105894