Friday, March 28, 2008

Copper : An Important Natural Resource

We're in no danger of running out of copper. Known worldwide resources of this important and valuable metal are estimated at nearly 5.8 trillion pounds of which only about 0.7 trillion (12%) have been mined throughout history.
And keep in mind, nearly all of that 0.7 trillion (or 700 billion) pounds is still in circulation because copper's recycling rate is higher than that of any other engineering metal.
Until well into the 1800s, most copper used in the U.S.A. had to be imported. Today, we are virtually self-sufficient and, worldwide, second only to Chile in production.
Each year in the U.S.A., nearly as much copper is recovered from recycled material as is derived from newly mined ore. Excluding wire production, most of which uses newly refined copper, more than three-fourths of the amount used by copper and brass mills, ingot makers, foundries, powder plants and other industries comes from recycled scrap.
Almost half of all recycled copper scrap is old post-consumer scrap, such as discarded electric cable, junked automobile radiators and air conditioners, or even ancient Egyptian plumbing. (Yes, it's been around that long.)
The remainder is new scrap, such as chips and turnings from screw machine production.


Since 1963 (the year CDA was established), more than 28 billion feet or about 5.3 million miles of copper plumbing tube has been installed in U.S. buildings. That's equivalent to a coil wrapping around the Earth more than 200 times. The current installation rate now exceeds a billion feet per year.
More than 9 out of 10 plumbers (94%) use copper tube in their own homes.


Copper is the standard benchmark for electrical conductivity. It conducts electrical current better than any other metal except silver.
Copper is routinely refined to 99.98% purity (even more pure than Ivory Soap) before it is acceptable for many electrical applications.
Number 12 (AWG) copper wire is the most common size used for branch circuit wiring in buildings. The amount of copper products consumed in the U.S.A. this past year would make a size 12 wire that could encircle the Earth 2,630 times or make 140 round trips to the Moon.
CDA's Electrical Energy Efficiency program illustrates how a simple upsizing of copper conductors used for electrical distribution can earn significant paybacks to building owners, usually within one to two years or less.
Installing #10 AWG wire instead of #12 AWG for feeding a 15-amp lighting load running half time (4000 hours per year) pays back the difference for its higher cost in only 9 months, at $0.075 per kilowatt-hour (kWh).
Because half of all the electricity generated in the U.S. is consumed by motor-driven systems, the most significant energy savings are realized by upgrading systems with high-efficiency motors.
A high-efficiency 3-hp motor operating full time at $0.08 per kWh would repay its cost premium in less than 5 months, and from then on save money and electricity.
Premium motors are not only more efficient (mostly because they are made with more copper), they also last much longer and generate less heat.
Wherever electricity flows, connectors are required. Copper in its many varieties is the dominant and favored material whether conductors are used for high-current power distribution or "signal" level currents used for data and telecommunications.
Some high-power connectors weigh in at 20 pounds or more, while tiny electronic connectors may weigh as little as a few milligrams with spacing between pins less than half a millimeter. The United States is the world's leader in the multibillion-dollar connector industry.
A consortium assembled by the Copper Development Association is working on a project to develop die materials for use in casting copper motor rotors. Such rotors would dramatically increase motor efficiency. Commercialization of the process is expected in 2002.
Power quality problems that plague many modern offices and factories are largely preventable. Copper-intensive solutions include using larger neutral conductors to handle harmonic loads, better grounding systems to dissipate transients and lightning, and fewer outlets per circuit to lessen interaction between office equipment and computers.
Scores of lives and billions of dollars in property could be saved each year if buildings were properly protected against lightning. A single lighting strike at a commercial facility could cause thousands of dollars per hour in lost production.
Copper and its alloys are the most common and most effective materials used in lightning protection.
Nearly 50 tons of high conductivity, oxygen free copper wire was used to make 1,700 super conducting electromagnets for a collider at the Brookhaven National Laboratory in New York. The magnets are used in the 2.4-mile diameter underground collider to study subatomic particles.

Copper Facts

Production & Consumption
U.S. copper mine production in 2002 dropped to 2,516 million pounds from 2001's 2,954 million pounds.
The 2002 level of 7,313 million pounds is a 6.0% decrease from the revised 2001 level of 7,780 million pounds.
Exports of mill products in 2002 continued to decline also, down 7.1% at 735 million pounds versus imports of 909 million pounds, a decrease of 10.0% from 2001 levels.
Building construction continued to be the largest end-use market for copper products, accounting for more than two-fifths, 46.3% (3,384 million pounds), of total U.S. consumption. Other end-use markets:
Electrical and electronic products - 22.7%(1,662 million pounds)Transportation equipment - 10.2%(744 million pounds)Consumer and general products - 10.9%(798 million pounds)Industrial machinery and equipment - 9.9%(725 million pounds)
The most current annual market data figures may be found in the market data section.

Friday, March 21, 2008

Brass part

We brass part are in business of precision brass components and are well situate with technical and experienced staff to look after the quality of all the products.We assure that all parts which we supply are totally attuned and interchangeable with the matching original part and all critical dimensions and tolerances are in accordance with original equipment specifications. Our production undergoes stringent quality control tests results our products to be of world class. To meet the global demand of gradually more high standards, our position is managed by highly expert staff, right from purchase raw material to finished good. Attention to detail at all stages of production has enabled us to survive to a repute of delivering on schedule. Manufacturer of brass automobile parts, brass bolt, brass earthing components, brass lpg parts, brass sanitary parts, brass building hardware, fasteners, brass auto parts, brass turned parts, brass electrical parts, brass precision parts, brass screw, socket pins, brass special parts, brass turned parts, brass electronic parts, brass screw, brass wedge fasteners, brass concrete fasteners, brass fittings, bronze and copper fittings and components and custom design.

Brass cable gland

We offer wide range of brass cable gland . Our products range in brass electrical accessories and wiring accessories including cable glands and cable glands accessories. Brass cable glands and cable glands accessories include BW type cable gland, A2,A1/A2 Cable Gland, BW Cable Gland, BW2 Part Cable Gland, BWR Part Cale Gland, BW4 Part Cable Gland, CW Cable Gland, CW3 Part Cable Gland, E1W Cable Gland, PG Cable Gland, Alco Cable Gland, Marine Cable Gland, TRS Cable Gland, Wiping Gland, Split Bolt Cable Gland, Aluminium Cable Gland & amp; Accessories, Brass Flexible Adaptor We are also Manufacturer and exporter of brass machine screws, cable gland, electrical accessories, cable glands accessories, wiring accessories, electronic component, fasteners, sanitary fittings, pipe fittings, conduit fittings, bicycle tube valve, terminal blocks, electrical connectors, electrical switch parts, plug pins and pin sockets. Machine screws are available in pan, flat, oval, cheese, and fillister head. We also manufacture machine screws as per customer requirements.

Brass billets rods Ltd.

We are involved in the manufacturing and exporting of non ferrous alloys, copper & copper alloy tubes, Brass billets Rods, Copper Alloy Ingots, Brass Ingots, Bronze Ingots, Zinc Ingots, Lead Ingots, Copper Alloy Billets, Brass Billets, Bronze Billets, Zinc Billets, Rods / Bars Copper Alloy Rods / bars, Brass Rods / bars, Bronze bars / Rods, Profiles Copper Alloy profile, Brass profile, Bronze profile, Pipes / Tubes Copper Alloy Pipes / Tubes, Brass profile Pipes / Tubes, Bronze profile Pipes / Tubes, Sheets Copper alloy sheets, Brass Sheets Bronze, Brass Billets Rods. We are constantly endeavoring to offer high quality products. Through commitment with quality, cutting edge technology and innovation, we have found a foothold in the industry. Our splendid range of products are of high quality and endurance. We upgrade our technology to face the global challenges and to meet the exacting requirements of our clients. We are a customer driven company which makes satisfaction of our client our priority set up a state of art manufacturing facility for melting, casting, extrusion, cold drawing, finishing, inspection & testing .
Manufactures copper alloy extrusions like extruded brass rod, profile, section, and imports zinc ingots, brass scrap, and copper scrap.copper alloy extrusions, extruded brass rod, extruded profile, extruded section, brass and copper scrap, zinc ingots, brass extrusions, rods, sections, profiles, honey scrap, buyer of scrap, birch copper scrap, copper scrap, Brass Billets Rods, manufacturer, exporter, importer, scrap importer, jamnagar, india

Brass electrical parts

We are pleased to introduce ourselves as a pioneer of Brass Pin, Brass Neutral Links, Brass Nickle Plated Electronic, F Connectors, Brass Electrical Accessories like Reducer, Earthing Tag, Screw Coupling, Test Bond, Split Bolt, Brass Earthing Accessories like Erath Rod, Coupler, Split Connected Clamp, Earth Rod to Cable Clamp (G Type), Rod to Tape Clamp (A Type), Brass Electrical Switch Parts, Panel Board Accessories, Electrical General Components, Electrical TNC Connectors and all type of Brass Electrical Parts as per customers specifications and drawings.

Brass Terminal Connectors Co.

We are pleased to introduce ourselves as a pioneer of Brass Battery Terminals, Brass Connectors, Brass adaptors(male & female), Brass Electrical Components, Pcb Terminals, Brass Electrial Plug Pins & Socket Pins, Brass Hrc fuse Contacts, Brass Currents Terminals & Potential Terminals, Copper Lugs Copper Terminals, Brass Copper Pins Insert, Brass Switchgear Panel Board Fittings Accessories, Brass Electrical Accessories, Terminal Blocks and all type of Brass Terminal Connectors as per customers specifications and drawings.We have an experience in this field of manufacturing different type of precision components and fasteners for more then a decade.Our unit is equipped with highly precision automatic as well as some semi automatic machineries, skilled labors and good quality control.Now a day we are supplying to many ISO 9001 companies world wide.We ensure that every components and fasteners produced at our plant matches in minutest details, those made by technologies any where in the world. We aim to deliver products with “Zero” defects with very optimum prices.

Brass sanitary

We are pleased to introduce ourselves as a pioneer of Brass Sanitary, Plumbing and Pipe fitting Brass Elbow, Brass Union, Brass Extension, Brass Nipple, Brass Reducer, Brass Extension, Brass socket, Brass Tee, Brass Connector, Brass Forging, Brass Stop Plug, Brass Bib cock, Brass Filter cock, Brass Strainer, Brass Nozzle, Brass Flange, Brass Plug, Brass Cap, Brass 3 PC connector, Brass Gas Connector Nozzle ( M/F ) , Brass Hex Nut / Check Nut Brass Waste Complete Sat, Brass Reducing Hex Bush, Brass Extension Reducer and all type of precision Brass turned or punched components as per customers specifications and drawings.We have an experience in this field of manufacturing different type of precision components and fasteners for more then a decade.Our unit is equipped with highly precision automatic as well as some semi automatic machineries, skilled labors and good quality control.Now a day we are supplying to many ISO 9001 companies world wide.We ensure that every components and fasteners produced at our plant matches in minutest details, those made by technologies any where in the world. We aim to deliver products with “Zero” defects with very optimum prices.

Brass Nut Bolt

The company has been more and more specializing in the forging and maching of brass union nuts and similar parts (flare nuts and brass nuts in general), Milled Nuts, Cap Nuts, Comperssion Nuts, Water Connection, Union Nuts, Union Nuts for Gas, Flare Nut, (M/F) Nuts, Blind Nuts, Fitting Parts, Hose Connection, Hub Nuts, Check Nuts, Nyloc Nuts, Lock Nuts, Hot Forged Nuts, Cold Forged Nuts, Coupling Nuts, Washers, Thread Bar, Square Nuts, Hub Bolts, U Bolts, Allen Key Bolts, Carriage Bolts, Torque Arm Bolts, Long Bolts, Center Bolts, Shackle Bolts, Equalizer Bolts, T Bolts, Axle Stud, Split Bolts, Slotted Bolts, Hanger Bolts.
Nowaday our production facilities cover in exporting many country like U.S.A, Canada, Sri Lanka, Dhaka, Bangladesh, Japan, Belgium, Nether land, Green land, Poland, Holland, Denmark, Dubai, Saudi Arabia, Brazil, Colombia, Tanzania, Ethiopia, Zambia, Egypt, Namibia, Iran, Iraq, Tehran, Germany, England, Poland, Bahrain, with a daily production capacity in eccess of a million pieces of brass nuts and similar parts thanks to our forging department and machining department. Moreover our quality control give to our brass nuts production a "state of the art" standard quality.
"The pursuit of flexibility and the research for the latest technologies are always our main goal."An example of our brass nuts production brass union nuts, flare nuts or blind nuts and brass is focused in these fields with technologies and flexibility to answer to customers' requests for brass nuts Bolt.

Brass Components Fasteners

Since 2000, We are in trade of brass components fasteners and well equipped with technical and experienced staff to look after the quality of all the products. We assure that all parts which we supply are totally compatible and tolerances are in accordance with original equipment specifications. Our production stringent quality control tests. Which results our products to be of world class. To meet the global demand of increasingly high standards, our plant is managed by highly skilled staff, right from purchasing raw material to finished good. Attention to detail at all stages of production has enabled us to live up to a reputation of delivering on schedule.
Manufacturer of brass auto parts, brass Screw, brass rivets, brass Washers, brass Pneumatics Parts, brass fastener, brass automobile parts, brass Inserts,brass electrical parts pin & sockets.

Brass fit

Welcome to the website of the BrassFit leading Manufacturer of brass, chrome-plated brass, and pipe nipples. Brassfit also manufactures special nipples in various lengths and types of machined ends. In addition, Brassfit offers a complete package of Brass fittings adapters, brass pipe fittings, valves and fittings most complete of cast brass fittings, flanges and pipe. Brass fittings manufacturer and exporter of Gas Connectors, Gas Valves, And OEM Assemblies, OEM Assemblies for Fireplace, Stove, and Barbecue Applications Full Line of Brass Fittings for LPG, Natural Gas, and Wetter CMI brass fittings seat brass tails and nipples for flexible hoses are made to be used with brass nuts. We can also offer free sampling for customers so that they can get the fittings approved before bulk supply. Our main manufacturing techniques are brass bar turning and machining, pressing, hot stamping. Professional engineering expertise combined with yearns for specialization offers cost effective solutions to the exacting needs of our customers. Professional engineering, cost-effective solutions, commitment to quality and a focus on specialization, identifies bfi as company that, manufactures a vast range of high quality. Threads bsp (gas), bspt, npt and metric Gas Connectors, Gas Valves, And OEM Assemblies, OEM Assemblies for Fireplace, Stove, and Barbecue Applications Full Line of Brass Fittings for LP,Natural Gas, and Watter.These products are an exclusive basis to customers, some are well known throughout the electrical industry worldwide if you require a product manufactured exclusively to yourself not found in our range, whether new or an old original, we have a team of management, tool makers and a work force capable to serve your needs.

Brass live company

Since 1989, We are in trade of precision brass components and are well equipped with technical and experienced staff to look after the quality of all the products.We assure that all parts which we supply are totally compatible and interchangeable with the corresponding original part and all critical dimensions and tolerances are in accordance with original equipment specifications. more..We are Leading Manufacturer & Exporter of Brass Fasteners, Brass nuts, Brass bolts, Brass Anchors, Brass Screws, Brass Inserts, Brass Terminals, Brass Electrical Accessories, Brass fasteners, Brass Hose Fittings, Brass Pipe Fittings, Brass forged parts, Brass Pin, Brass Connectors, Brass Turned Components, Brass Part Products, Brass Precision Parts, Or any kind of Precision Brass Parts. We have Customers From UK, USA, Australia, Africa, Europe & Asia.

Brass part fittings

We are a specialist in industrial supplements as we provide the best quality Brass Precision Components, Micro precision brass turned components, Precision turned components have a wide range of application for manufacturers automobiles industry, telecommunication sector and the electronic industry. These products are available in raw, polished and nickel plated finishes. Apart from the standard range of products we specialize in a wide range of brass turnings from 5mm to 100mm. Our company Manufacturing & Exporting Precision Brass Components including Brass Building Hardware, Brass Furniture Fitting, Brass Electric & Electronic Components, Brass Battery Terminals, Brass L.P.Gas fittings, Brass Antique Pieces, Brass Lamp Parts, Brass Conduit Fittings, Brass Sanitary Fittings, brass Compression Fittings, Brass Forged Components Brass fasteners, Brass Anchors, Brass precision turned components etc. Our products are proffered in various shapes and sizes as per your requirements. Our precision brass components designed in a way that they are able to sustain in any diverse circumstances. Our products’ accountability and overwhelming feedback of our consumers have pushed us towards being one of the supreme Brass Components Manufacturers and supplier in India. Please have a look of our website

Deep Recycling Industries

Deep Recycling Industries (DRI), is 100% Export Oriented Unit, established in the year 2002 by ‘VIKAS’ group and engaged in manufacturing wide range of brass parts, specialist in electrical accessories, pneumatics parts, energy meter parts, temperature sensor, cable glands, marine gland, automotive parts, Brass fasteners, precision turned components, Brass and Copper Ingots/Billets/Rods/Granules, Tube, Wire, Plates, Pipes, Electrical Accessories, Brass Hardware, Sanitary Fittings, Wiring Accessories and Components , brass anchors, wedge anchor, concrete anchor, brass inserts, brass bolts, brass washers, brass screws, brass nuts, machine screws and self tapping screws, Auto parts, Automobile battery terminals and general brass components as per customer specifications / requirements. For more information pls visit us at

Saturday, March 15, 2008

Zinc and Crops

Zinc is essential for the normal healthy growth and reproduction of plants, animals and humans. When the supply of zinc to plants is inadequate, crop yields are reduced and the quality of crop products is often impaired.
Zinc is required in small but critical concentrations to allow several key plant physiological pathways to function normally. These pathways have important roles in:
Photosyhthesis and sugar formation
Protein synthesis
Fertility and seed production
Growth regulation
Defense against disease.
Where zinc is deficient these physiological functions will be impaired and the health and productivity of the plants will be adversely affected, resulting in lower yields (or even crop failure) and in poorer quality crop products.
Very many plant species are affected by zinc deficiency on a wide range of soil types in most agricultural regions of the world. The major staple crops (rice, wheat, maize and sorghum) are all affected by deficiency together with many different fruit, vegetables and other types of crops including cotton and flax.
Yield losses of 40% or more can have a major economic impact on the farmer due to the reduced income. The economic impact is even higher when expensive inputs such as seeds, fertilizers, agricultural chemicals and irrigation water are involved. In developing countries, the cost from significant shortfalls in food production can also be considerable because increased imports of grains will often be required to make up this shortfall.
Zinc deficiency can be identified by soil testing or the analysis of the crop plants (usually leaves) and can be easily corrected by treating the deficient soils and crops with zinc fertilizers.

Zinc use in brass

The Brass FamilyBrass is not a single unique metal. Rather, the brasses comprise a family of copper-base alloys in which zinc is the principal alloying element. The amount of zinc present in these alloys ranges from 10% to more than 40%. Besides its traditional use for door handles, lighting fixtures and decorative objects, brass is now an increasingly popular material with architects, interior designers and consumers.Brass has a warm, natural colour and feel. Brass is also a hygienic material - when used for handles, railings and hardware, it has the added benefit of being bacteriostatic.
The names given to alloys in the brass family are, in some cases, as colorful as the metals themselves. Historically and technically, brass is defined as any alloy in which the principal constituents are copper and zinc. Thus, all brasses contain zinc, although other elements may be present.
That convention notwithstanding, design parlance collectively identifies all of these alloys as "bronzes", mainly because of their similar uses, colors and weathering characteristics. For example, designers and architects speak of "white bronzes", "yellow bronzes", "statuary bronzes" and even "green bronzes" (after weathering). In fact, the majority of the metals so identified are brasses, or alloys of copper and zinc.
Cast brasses offer almost infinite possibilities for artistic expression, not simply for statuary, but as decorative hardware, innovative plumbing fixtures and architectural details. Moreover, cast brasses can be selected by color to match - or contrast - the colors of most wrought brass alloys, an important advantage.
Ageless beautyThe brasses we normally think of are bright yellow in color. Brasses can retain that color indefinitely if properly protected with suitable finishes, but the way brasses change color as they age opens an entirely new dimension to their use in architecture. The very pleasing - and from a corrosion standpoint, very protective - natural patinas that brasses assume as they age have become synonymous with durability and lasting quality. Architects, designers and sculptors take creative advantage of brass's gradual change in appearance to underscore the timelessness of their structural creations.
Today, it is possible to accelerate brass's ageing process through the application of chemical treatments. These "artificial patinas" create within hours the protective mineral surface finishes that would take decades to form in nature. Alternatively, durable lacquers and polymeric laminates are now available that can retain the natural beauty of new metal for years, whether indoors or exposed to the atmosphere. The recent development of extremely age-resistant protective finishes, including powder coatings and vapor-deposited organic coatings, is one of the major driving forces behind brass's growing popularity. Interestingly, some architects have found that the combination of aged patinas and bright "new" metal finishes is especially appealing. The variety of surface finishes and colors available in brass is one more expression of the metal's almost endless variety.

Environmentally friendlyFinally, it is important to understand that brass is an environmentally friendly metal. Its constituents, copper and zinc, are produced today by energy-efficient processes. More important, though, is the fact that brass is one of the most thoroughly and efficiently recycled of all industrial metals. When brass articles are no longer needed, they are almost never discarded, and brass rarely, if ever, finds its way to a landfill. Rather, brass is remelted and reprocessed to "new" brass many times over. It is simply too valuable to throw away. The efficient recycling process has been going on for thousands of years. Think about that the next time you see a brand new brass product - its family tree may include recycled products that are centuries old.

Zinc: First & End Uses

Over 7 million tons of zinc are produced annually worldwide. Nearly 50% of the amount is used for galvanizing to protect steel from corrosion. Approximately 19% are used to produce brass and 16% go into the production of zinc base alloys to supply e.g. the die casting industry. Significant amounts are also utilized for compounds such as zinc oxide and zinc sulfate and semi-manufactures including roofing, gutters and down-pipes.
These firt use suppliers then convert zinc into in a broad range of products. Main application areas are: construction (45%) followed by transport (25%), consumer goods & electrical appliances (23%) and general engineering (7%).

Zinc Recycling

At present, approximately 70% of the zinc produced worldwide originates from mined ores and 30% from recycled or secondary zinc. The level of recycling is increasing each year, in step with progress in the technology of zinc production and zinc recycling. Today, over 80% of the zinc available for recycling is indeed recycled.
Zinc is recycled at all stages of production and use – for example, from scrap that arises during the production of galvanized steel sheet, from scrap generated during manufacturing and installation processes, and from end-of-life products.

Zinc-coated steel and other zinc containing products are slow to enter the recycling circuit due to the very nature of their durability. The life of zinc-containing products is variable and can range from 10-15 years for cars or household appliances, to over 100 years for zinc sheet used for roofing. Street lighting columns made of zinc-coated steel can remain in service for 40 years or much longer, and transmission towers for over 70 years. All these products tend to be replaced due to obsolescence, not because the zinc has ceased to protect the underlying steel. For example, zinc coated steel poles placed in the Australian outback a hundred years ago are still in excellent condition(3).
The presence of zinc coating on steel does not restrict steel's recyclability and all types of zinc-coated products are recyclable(4). Zinc coated steel is recycled along with other steel scrap during the steel production process - the zinc volatilises and is then recovered.
Zinc coated steels are easily collected and treated in existing process streams. The Electric Arc Furnace (EAF) is the most widely used process for recycling zinc-coated steel. The high temperatures cause zinc - which is volatile at high temperatures - to leave the furnace along with other gases. The gas stream is treated and the zinc collected in the dust, of which zinc (18-35%) and iron are the main constituents. These dusts undergo an enrichment process in a rotary kiln, known as a Waelz kiln. This leads to the production of zinc oxide, which in turn becomes a raw material for the production of zinc metal. Several new technologies are in use or under development for processing EAF dusts and the valuable metals they contain.

The Production of Zinc

Over 95% of the world’s zinc is produced from zinc blende (ZnS). Apart from zinc the concentrate contains some 25-30% or more sulphur as well as different amounts of iron, lead and silver and other minerals. Before metallic zinc can be recovered, by using either hydrometallurgical or pyrometallurgical techniques, sulphur in the concentrate must be removed. This is done by roasting or sintering. The concentrate is brought to a temperature of more than 900°C where zinc sulphide (ZnS) converts into the more active zinc oxide (ZnO). At the same time sulphur reacts with oxygen giving out sulphur dioxide which subsequently is converted to sulphuric acid – an important commercial by-product.

The history of zinc

Centuries before zinc was discovered in the metallic form, its ores were used for making brass and zinc compounds, its ores were used for healing wounds and sore eyes. It is believed that the Romans first made brass in the time of Augustus (20 B.C. – 14 A.D.). In the 13th century Marco Polo described the manufacture of zinc oxide in Persia.
By 1374, zinc was recognized in India as a new metal – the 8th metal known to man at that time. At Zawar, India, both zinc metal and zinc oxide were produced from the 12th to the 16th century. Zinc metal was used to make brass and zinc oxide served medical purposes.
From India, zinc manufacturing moved to China in the 17th century where it developed as an industry to supply the needs of the brass industry.

Zinc was recognized in Europe as a separate metal in the 16th century when Agricola (1490 – 1555) observed that a metal called “zincum” was produced in Slesia and Paracelsus (1493 – 1541) stated clearly that “zincum” was a new metal. In 1743, the first European zinc smelter was established in Bristol in the United Kingdom using a vertical retort procedure. A major technological improvement was achieved with the development of the horizontal retort process in Germany which led to the erection of smelting works in Slesia, Liege, Belgium and Aachen, the Rhineland and the Ruhr areas in Germany. In 1836 hot-dip galvanizing, the oldest anti-corrosion process, was introduced in France. Zinc production in the United States started in 1850.

For about 500 years zinc was produced from its oxide ores before the more abundant sulfides became the major source of supply. On the technological side there was a drastic change in 1916 when the electrolytic process was introduced on a large scale replacing the pyrometallurgical process as the dominating production method.

Monday, March 10, 2008

Brass sheet, strip and wire

The 70/30 brass to be made into sheet, strip or wire form must be significantly free of harmful impurities in order to retain ductility when cold. It can then be rolled, drawn, deep drawn, swaged, riveted, spun or cold formed. It is normal therefore to make it substantially from virgin copper and zinc, together with process scrap arising from processing that has been kept clean, carefully segregated and identified.

Special purpose alloys

Brass swarf arising from machining operations can be economically remelted but it should be substantially free from excess lubricant, especially those including organic compounds that cause unacceptable fumes during remelting. The presence in brass of some other elements such as lead is often required to improve machinability so such scrap is frequently acceptable. Besides the common free-machining brasses, there are many others made for special purposes with properties modified to give extra strength, hardness, corrosion resistance or other attributes, so strict segregation of scrap is essential.
When brass is remelted, there is usually some evolution of the more volatile zinc. This is made up in the melt to bring it back within specification. The zinc is evolved as oxide that is drawn off and trapped in a baghouse and recycled for the manufacture of other products.

Brass machined parts and stampings

Free machining 60/40 brass with small additions of lead is particularly cost-effective and environmentally friendly when used for the manufacture of machined parts and stampings. Firstly, the swarf produced as a result of high speed machining (typically metal removal rates are two to three times those of mild steel) can be sold as scrap. Secondly, when brass components reach the end of their long and useful life they too can be readily recycled. The stamping temperatures for brasses are lower than those required for ferrous alloys making it an energy efficient process; the low stamping temperature also gives an increased die life. Stamping is a near-net-shape process but the small amount of swarf produced by machining is again recyclable. Brass is also cost-effective and kind to the environment because it does not normally need plating or painting to prevent corrosion.

Types of Brass

Effects of alloying additions
Free machining brasses
High tensile brasses
Effect of processing on properties
Effect of zinc content on properties
Available forms and properties

Forms of Brass

Describes the extensive range of shapes and sizes available and the way in which they can be made. There is also coverage of the old British standards and material designations and the EN standards and designations which have replaced them.

Hot stampings
Sheet and strip
Ordering Information
Case histories

Why Make it in Brass?

Explains the very wide variety of combinations of properties unique to brasses that make them the most cost-effective materials to select for the manufacture of a vast range of products.
Low cost manufacturing
Corrosion Resistance

Sunday, March 09, 2008

Overview of Brass

Brasses are copper zinc alloys. In general, they have good strength and corrosion resistance, although their structure and properties are a function of zinc content. Alloys containing up to approximately 35% zinc are single phase alloys, consisting of a solid solution of zinc and alpha copper. These brasses have good strength and ductility, and are easily cold worked. The strength and ductility of these alloys increases with increasing zinc content. The alpha alloys can be differentiated by a gradual change in color, from golden yellow to red, as the zinc content is increased up to 35%. Gilding 95%, Commercial Bronze, Jewelry Bronze, Red Brass and Cartridge Brass are in this category of brasses. These are known for their ease of fabrication by drawing, high cold worked strength and corrosion resistance. Increasing the zinc content up to 35 % produces a stronger, more elastic brass alloy with a moderate decrease in corrosion resistance. Brasses containing between 32 and 39% zinc have a two phase structure, composed of alpha and beta phases. Yellow brasses are in this intermediate category of brasses. Brasses containing more than 39% zinc, such as Muntz metal, have a predominantly beta structure. The beta phase is harder than the alpha phase. These materials have high strengths and lower ductility at room temperature than the alloys containing less zinc. The two phase brasses are easy to hot work and machine, but cold formability is limited. Brasses are used in applications such as blanking, coining, drawing, piercing, springs, fire extinguishers, jewelry, radiator cores, lamp fixtures, ammunition, flexible hose, and the base for gold plate. Brasses have excellent castability, and a good combination of strength and corrosion resistance. The cast brasses are used in applications such as plumbing fixtures, fittings and low pressure valves, gears, bearings, decorative hardware and architectural trim. The UNS designations for wrought brasses includes C20500 through C28580, and C83300 through C85800 for cast brasses.
Certain brasses can corrode in various environments. Dezincification can be a problem in alloys containing more than 15% zinc in stagnant, acidic aqueous environments. Dezincification begins as the removal of zinc from the surface of the brass, leaving a relatively porous and weak layer of copper and copper oxide. The dezincification can progress through the brass and weaken the entire component. Stress corrosion cracking can also be a problem for brasses containing more than 15% zinc. Stress corrosion cracking of these brasses occurs when the components are subject to a tensile stress in environments containing moist ammonia, amines, and mercury compounds. If either the stress or chemical environment is removed the stress corrosion cracking will not occur. Sometimes a stress relieving treatment is sufficient to prevent stress corrosion cracking from occurring. The microstructure of the single phase brass alloys, with up to 32% zinc, consists of a solid solution of zinc and alpha copper. The as-cast structure of the low zinc brasses consists of alpha dendrites. The first material to solidify is almost pure copper, as the dendrites continue to solidify they become a mixture of copper and zinc. A composition gradient exists across the dendrite, with zero zinc content at the center and highest zinc content at the outer edge. The composition gradient is called coring, and it typically occurs with alloys that freeze over a wide temperature range. Subsequent working and annealing breaks up the dendritic structure. The resulting microstructure consists of twinned, equiaxed grains of alpha brass. The annealed microstructure is made up of equiaxed, twinned grains of alpha copper, similar to the structure of unalloyed copper. The grains appear in different shades due to their different orientations. The twins are parallel lines that extend across individual grains. The twins result from a fault in the staking sequence of the copper atoms, making it difficult to distinguish the individual grains.
Alpha copper is the primary phase in cast alloys containing up to approximately 40% zinc. The beta phase,which is the high zinc phase, is the minor constituent filling in the areas between the alpha dendrites. The microstructure of brasses containing up to approximately 40% zinc consists of alpha dendrites with beta surrounding the dendrites. The wrought materials consist of grains of alpha and beta. Cast alloys with greater than 40% zinc contain primary dendrites of beta phase. If the material is fast-cooled, the structure consists entirely of beta phase. During a slower cool, the alpha precipitates out of solution at the crystal boundaries, forming a structure of beta dendrites surrounded by alpha. This structure is called a Widmanstatten structure, because a geometrical pattern of alpha is formed on the certain crystallographic orientations of the beta lattice. The wrought, two phase material consists of grains of beta and alpha. Hot rolling tends to elongate the grains in the rolling direction.
Brasses frequently contain lead in order to improve machinability. The microstructure of the leaded brasses is similar to that of the unleaded brasses with the addition of almost pure lead particles found in the grain boundaries and inter-dendritic spacings. The lead is observed in the microstructure as discrete, globular particles because it is practically insoluble in solid copper. The number and size of the lead particles increases with increasing lead content.

Overview of Copper

The major uses of pure, unalloyed copper are based on its high electrical and thermal conductivity as well its good corrosion resistance. Almost all alloying elements are detrimental to the electrical conductivity of copper, making the purity of the mental an important issue. Commercially pure copper is represented by UNS numbers C10100 to C13000. The various grades of unalloyed copper differ in the amount of impurities and therefore do behave differently. Oxygen free coppers are used in applications requiring high conductivity and exceptional ductility.
The pure copper or high copper alloys are made from copper ores that are obtained from the mines as sulfides, which contain zinc, lead and other sulfur. The ores are crushed and milled until they becomes a powder. A technique known as flotation separates the metal from the non-metal components of the powder. The next step is a concentrating stage where minerals are concentrated into a slurry that is about 15% copper. The copper is then melted and purified in several stages until it is 99% pure copper. At this point it is cast into anodes. Oxygen remains in the structure as cuprous oxide, Cu2O. The majority of the structure is pure copper. The copper metal solidifies from the liquid state by the growth of crystals. The crystals grow in preferred directions and form open, tree like structures called dendrites. The dendritic structure is very typical of cast metals. A lower melting point mixture of pure copper and cupprous oxide, called a eutectic, forms in the open spaces between the dendrites. The eutectic particles are usually dark, globular bodies dispersed in a copper background. The cuprous oxide particles form a network, outlining the dendritic cells. Pores, seen as dark spots in the microstructure, are also present in the as-cast material.
The copper anodes are then refined electrolytically to 99.9% purity. Copper melted under non oxidizing conditions is called oxygen free copper. The most popular form of pure copper is the standard electrical wire grade of copper (C11000) contains 99.95% Cu, 0.03% O2, and less than 50 ppm metallic impurities. It has a high electrical conductivity, in excess of 100% IACS. In the as cast form it is called electrolytic tough pitch (ETP) copper. The structure of the as-cast material is similar to that described above. When the as-cast ETP copper is hot rolled the eutectic structure is completely destroyed. The microstructure of the hot rolled copper contains many small grains. Parallel straight lines extending across many of the grains are called annealing twins. They appear after a metal has been mechanically worked at a high temperature, called annealing, and deformed. The interdendritic network of cupprous oxide particles was destroyed by hot rolling. After hot rolling, cupprous oxide particles changed form, and are present as stringers or aligned rows of dark particles. The oxide particles are much larger and fewer in number than in the as cast microstructure.

What is RoHS ?

The RoHS Directive stands for "the restriction of the use of certain hazardous substances in electrical and electronic equipment". This Directive bans the placing on the EU market of new electrical and electronic equipment containing more than agreed levels of lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyl (PBB) and polybrominated diphenyl ether (PBDE) flame retardants. Manufacturers need to understand the requirements of the RoHS Directive to ensure that their products, and their components, comply.

Non-ferrous prices and currency affects indian import

Copper as base metal in LME (London Metal Exchange) moving towards its life high. Improving a little appreciation of US$ and Euro against Indian currency cause the raw-material scrap costs high. Euro has achived its life time high against Indian Rupees as 62.50 per euro. In terms of import from european country in costiler comparetaly to other neighbour countries.