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Showcasing Different Types of Foundry Castings, Stainless Steel, Ductile Iron & Gray Iron Castings

Showcasing Different Types of Foundry Castings, Stainless Steel, Ductile Iron & Gray Iron Castings

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Home Page > Business > Industrial > Showcasing Different Types of Foundry Castings, Stainless Steel, Ductile Iron & Gray Iron Castings

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Showcasing Different Types of Foundry Castings, Stainless Steel, Ductile Iron & Gray Iron Castings

By: Rich Milton
Posted: May 25, 2011

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The International Industrial Trade Show (IITS), a virtual expo showcasing suppliers of various machines, tools and equipment for construction, engineering and manufacturing markets announced Wednesday the debut of its Castings Manufacturers Directory designed to help companies select the ideal casting to meet their needs. ArriveNEWS.com, an international B-to-B news aggregator and organizer of the online exhibition said the types of castings offered on the site is suitable for the small and large production of machine tools & components, heavy equipment parts, telecommunications, electronic & electrical, agricultural, computing, industrial processing systems, plastic injection molding, railroad, automotive, rubber & plastic manufacturing, aerospace/aircraft, military, general machinery, gears, valves, motion control products, power transmission equipment, government, consumer goods and other applications.

Juan Torres, spokesman for ArriveNEWS and the virtual trade show (IITS) said the Castings Manufacturers and foundries showcased on the site work with a large variety of metals and plastics such as aluminum, stainless steel, carbon steel, cast iron, ductile iron, brass, nickel alloy, aluminum die, bronze, zinc, titanium, non ferrous alloy, carbides, gray iron, high grade aluminum & bronze alloys as well as plastic materials. According to Torres, the types of castings offered include sand casting, investment, centrifugal, precision, lost wax, foundry castings, permanent mold, precision investment, steel iron as well as specialized abrasion and wear resistant castings in large and small loose or production patterns, including 3DP, MMJ, SLS and SLA.

The featured foundries and custom manufacturers showcased on IITS are capable of producing small, medium and extra large castings for a number of industries,” said Torres. He concluded, “Recent exhibitors added to the online exposition, in addition to existing offerings, include nearly 50 suppliers of shell molding, no bake mold, manganese, investment, aluminum, Ni hard, zinc, Meehanite, sand and investment castings primarily from the United States and China, but not limited to such markets.” Torres continued, “ArriveNEWS is committed to being the premier source for all kinds of castings for a broad range of industries custom made from virtually every available material offered in low, medium and high production quantities.”

About ArriveNEWS

ArriveNEWS.com is an online industrial expo organizer and producer of the International Industrial Trade Show (IITS 2010). The site utilizes a simple platform to showcase its exhibitors by using online videos to demonstrate a wide range of innovative industrial equipment, machine tools and technology offered by manufacturers across the globe with emphasis on products made in the USA at http://www.arrivenews.com/iits.html

Source: http://www.articlesbase.com/industrial-articles/showcasing-different-types-of-foundry-castings-stainless-steel-ductile-iron-gray-iron-castings-4815239.html

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Article Tags:
bronze castings, steel castings, iron castings, investment castings, brass castings, aluminum castings

Latest Industrial Articles
More from Rich Milton

What Are Shrink Wrapping Films

Shrink wrapping films are a material usually made of polymer plastic film that shrinks tightly over an object they are covering when heat is applied. A light weight shrink wrapping film is commonly used on many types of packaging such as cartons, boxes and pallets. This is often done using a heat shrink machine or other specialized equipment.

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The Pros and Cons of Used Pallet Racking

Business expenses can be overwhelming these days. From start up costs to upkeep staying out of the red means a lot of hard work, sacrifice and a good mind for money. Many businesses are finding ways to cut down on their costs without cutting down on the quality of service of good that they are putting out.

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Pressure Washing NC – A gleaming road to success

Recently, I had the honor of traveling to my brother’s place in the haven of the beautiful city of North Carolina, a city dreaded for having the maximum number of tornadoes, at least 20 per year, produced by tropical storms along the coastal plain.

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Global Minimally Invasive Vertebral Compression Fracture Surgery Market 2010-2014

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Fabrics & Textiles – Buying From Textile Mills vs. Fabric Wholesalers and Distributors

New textiles marketplace connects buyers and suppliers of automotive, commercial, medical, laboratory and industrial textiles

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Cable and Wire – How To Find Leading Wire and Cable Manufacturers Serving Your Industry

Stainless, copper, galvanized and other types of wire now being offered from U.S. manufacturers on the Buy American trade portal

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Business >
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Where To Find Surplus Building Materials and Salvage Building Materials

The US-Asia Trade Portal increases offerings for plywood, doors, windows, concrete and other building materials with new, salvage and surplus offerings

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Bearings Resources – A Look at the Materials, Applications & Leading Manufacturers of Bearings

The US-UK Industrial Trade Portal ForeignTRADEX increases offerings for bearings, shafts & other motion control products

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Why a Cast Iron Wood Stove is So Excellent and Accessories For Wood Heating

Why a Cast Iron Wood Stove is So Excellent and Accessories For Wood Heating

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Home Page > Home Improvement > Why a Cast Iron Wood Stove is So Excellent and Accessories For Wood Heating

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Why a Cast Iron Wood Stove is So Excellent and Accessories For Wood Heating

By: Mary Sykes
Posted: Mar 09, 2011

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If you have ever before heating your residence with a cast iron wood stove, you will know why they are so very good. But if you have only applied a fireplace, or major gage steel stove or fireplace insert, you just can not enjoy the distinction.

Cast iron has a lot of advantages more than boiler plate steel. It does not warp or discolor for starters. This tendency of steel stoves actually degrades the look of the stove and helps make it seem as if one thing is incorrect or damaged.

The only way you can actually harm a cast iron wood stove is to enormously overheat it. This is in fact challenging to do, but I’m confident an out of control fire left to itself could do some damage. You also could break it by dropping some thing quite major, but this is highly unlikely.

Both steel and cast iron will rust, if exposed to ample moisture. The cast iron will rust a lot more very easily, but this is also not a lot of a problem. A very little stove blacking paint will consider treatment of any rust spots or faded locations.

Steel stoves warmth up far more speedily and as a result give off a good deal of warmth proper absent. This is fantastic for spring and fall, when you may possibly only want to consider the chill off. Below standard working problems the surface will tend to be hotter as effectively, which tends to make it somewhat of a hazard and treatment ought to be taken to have sufficient clearance from combustible products. For a lot more information about “Boiler Stoves”, you ought to check out: Boiler Stoves

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Cast iron is slower to warmth up, and seldom genuinely turns into particularly scorching to the touch. This can make it considerably much less of a fire hazard, however treatment ought to usually be taken to set up it securely. This also helps make it a little safer for the family and tiny little ones. The stove can undoubtedly get really scorching to the touch, even so, and precaution ought to be taken for safety’s sake.

In quite a few techniques a excellent employed cast iron stove is equivalent to the publish and beam houses and barns identified in New England. These outdated, hand-hewn buildings have stood the test of hundreds of seasons and are even now completely practical. Quite a few old, higher high quality stoves are nonetheless in use, even immediately after a lot of decades of services.

Regardless of whether you have a cast iron or steel stove, you will need some standard accessories. Initial, make certain you have adequate floor covering to shield from very hot coals and ashes. Far more than 1 nice, hardwood floor has been damaged by stray coals that fall out in the course of the loading of firewood. This is true for both fireplace wood stoves and totally free standing stoves.

It is a straightforward make a difference of setting the stove up on a fireproof spot, and there are a lot of methods to complete this. You can get metal floor coverings, or merely set the stove up on bricks. If you want to genuinely do it correct, make a very little hearth spot out of decorative ceramic tiles, bordered with a frame of some kind. This is a stunning way to present your good searching stove.

If you lower your personal firewood, you will will need a excellent gasoline chain noticed, chains, sharpening tools, hearing protection, splitting maul, and have a firewood shed for storage.
Why a Cast Iron Wood Stove is So Very good and Accessories For Wood Heating

Mary Sykes – About the Author:

Admintratror

Source: http://www.articlesbase.com/home-improvement-articles/why-a-cast-iron-wood-stove-is-so-excellent-and-accessories-for-wood-heating-4373831.html

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Where Can I Find It? Looking for Architectural Styles

Many countries adopted this style at the end of later phase. This phase actually became a sort of subcategory of Neoclassicism, inspired by etchings and engravings. This style came to become known as the Greek Revival period. In fact, it became so popular that by the mid 19th century several cities in Europe were almost overrun with examples of the architecture, cities such as Athens, Berlin, Munich, and St. Petersburg.

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Cast Iron Guttering Is the First Choice for Your Traditional Country Home

Cast iron guttering is a fantastic choice for those who are looking for strong, durable, and aesthetically pleasing guttering system for their homes. The type of guttering system that has gained much popularity these days are the cast iron ones. This guttering system is made available by different manufacturers is very easy to install. The cast iron ones are attractive and add beauty to the outer appearance of your house. It gives an old world charm that you just cannot miss. Everybody will appreciate once you have made the installation. In UK, it has become very popular as it can assist in excessive amount of water drainage.

Cast Iron is a durable material and is extremely easy to maintain. If you properly maintain these gutters then these are surely going to last for a long time. It should be regularly cleaned so that they last for years to come. During maintenance, you should ensure that there is no seam leak. Check at the joints for any kind of damage. If any leak is detected then you should immediately repair it. You should first scrap off the paint and rust and then repaint the affected portion. You can get these cast iron gutters from a wide variety of manufacturers without any hassle. This is a very easy process and this would ensure that the gutters last for a long time.

With the whole world going eco-friendly, you should do your bit too and opt for the cast iron ones so that you do not do anything to damage the environment. These are made from eco-friendly materials and hence you should always choose to go for these guttering systems. Disinfect the interiors of the guttering system so that you and your family do not run the risk of falling ill. If you cannot do it on your own then you can take the assistance of professional people.

The cast iron guttering is more suitable for traditional style of home because they are durable and strong. They serve a functional purpose and also provide and can enhance the look of their house. Country house with the gutters of cast iron add a sophisticated charm to their houses. You are surely going to change the look of your house with your choice of guttering. The visual appeal of these houses is far more than other types of houses with different guttering system. The best part is that they are very easy to install and the process can be completed in just five easy steps.

Cast iron gutters is a great choice for your home. Hence, if you plan to install then choose to go for these gutters. Get proper knowledge so that it is easy for you to make the installation on your own. They are available at a discounted price so that you can easily make your purchases. Therefore, when you are buying choose carefully so that you can get the best deal.

www.bajranggears.com India based Bajrang Engineering Works, an ISO 9001 certified company, has made its mark in the domestic as well as international market as leading manufacturers and suppliers of high quality and competitively priced mechanical products such as automobile gears, industrial gears, helical gearbox, precise machinery spare parts and transmission parts for discerning clients everywhere. The range of mechanical components include industrial gears, automobile gears, spur gears, helical gears, bevel gears, and industrial gearbox range consists of planetary gearbox, helical gearbox, worm reduction gearbox, shaft mounted gearbox. Industrial Gears – http We are manufacturers and exporters of all kinds of industrial gears for industrial and machinery applications. We are equipped with design software and testing facilities for these gears required in power transmission. Automobile Gears – www.bajranggears.com We are manufacturers and exporters of Automobile Gears. BEW has a fully equipped plant with latest CNC Machines to manufacture Automobile Gears and Shafts for variety of vehicles. We undertake both prototype and production lots for these gears. Helical Gearbox – www.youtube.com We are manufacturers and exporters of Helical Gearbox. Helical Gear boxes for industrial applicantions are manufactured to ISO standard & recommendations. Shaft Mounted Gearbox – www.bajranggears.com We are manufacturers and exporters of Shaft Mounted Gearboxes. Helical Shaft Mounted …
Video Rating: 0 / 5

Information about Cast Iron and Its Benefits

Cast iron known as gray iron and it is one of the famous ferrous alloys for iron and metal industry. In cast iron carbon ( c) and silicon (s) are the main element with the amount of 2.1 to 4 wt% and 1 to 3 wt% respectively. Also you can mix Cr, Ni, Mo and Cu according to your requirement.

In India many Investment casting foundry used different ferrous metals such as carbon steel, alloy steel, stainless steel, cast iron for castings which formally known as ferrous castings. But they mostly prefer cast iron with its different compositions including white cast iron, gray cast iron, malleable cast iron, ductile iron etc. See below some basic description for above compositions.

White Cast Iron

White cast iron contains lower silicon and metastable phase cementite, Fe3C rather than graphite. It offers hardness with the rate of toughness. Generally white cast iron classified as cermet. Cast iron is used for structural components manufacturing for good hardness with low cost. Also it used for manufacturing or industrial parts such as slurry pumps, shell liners and lifter bars in ball mills and grinding mills, and the teeth of a backhoe’s digging bucket.

Grey Cast Iron

These types of cast iron characterize by its graphitic microstructure and its widely used cast iron based on weight. Cast iron having 2.5 to 4.0% carbon, 1 to 3% silicon so it’s pure iron also contain less tensile strength and shock resistance than ductile iron or malleable iron and its compressive strength is low then carbon steel. Many casting foundries used gray cast iron to manufacturing some general engineering components such as protective cover, cover, oil pan, hand wheels, frame, floor, hammer, small handle, machine base, frame, box, knife, bed, bearing seat, table, wheels, cover, pump, valve, pipe, flywheel, motor blocks.

Malleable Cast Iron

Its properties are same as mild steel property and it is heat treated iron with carbon alloy which solidifies with graphite free structures means carbon is present in the cemnetite form (Fe3C). This type of cast irons contains different chemical element composition such as carbon, silicon, manganese, sulfur, phosphorus etc. Also it possesses considerable ductility and toughness

All of the above cast iron compositions are widely used for making high quality and higher resistive part for industries. Also auto parts manufacturers in India widely used cast iron for making higher strength and corrosion free automotive parts with help of auto component castings

ductile iron & gray iron castings foundry in the USA. Mabry Castings LTD, www.mabrycastings.com

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Dr. Tschinkel demonstrates how he creates an aluminum cast of an ant colony.

Shanxi province from casting to casting into the province

Should rely on resources and energy advantages, strong brand advantage, to achieve industrial upgrading casting industry of our province. “Provincial Committee of the persons concerned by the letter and interview, has said. While” Shanxi foundry industry restructuring and rejuvenation plan “made it clear that by 2011 the annual production capacity controlled 800 million tons, sales income of 50 billion yuan, the formation of a group of highly competitive large enterprise groups and Unique casting industry cluster. the province formed a yearly sales income of 2 billion yuan more than three years, sales of 10 billion yuan, 10 500000000 yuan in sales revenue cast over key enterprises.

Foundry industry is an important part of equipment manufacturing, automotive, petrochemical, steel, electric power, shipbuilding, textile, equipment manufacturing and other pillar industries, based on national economic development and enhance the national defense forces play an important role. Casting a long history of our province, is the national important production base of casting, after years of adjustment of development, the province has formed high-strength cast iron, ductile iron, malleable iron, gray iron, carbon steel, stainless steel, aluminum-magnesium alloy and other materials in large supporting casting equipment manufacturing, automotive casting, basic mechanical precision castings, 3C casting, Pipe, etc. a full range of industrial system, nurtured Jincheng, Linfen, Yuncheng, Jinzhong, Luliang five high-precision casting industry cluster. But the province is not casting foundry province, and the foundry industry in our province compared to the same industry, there is low concentration of industry, business small and scattered, the quality of employees is not high, self-development and technological innovation capability poor, high-tech and too few high-value-added products, the level of poor working conditions and environmental protection issues.

To change this situation, adjust our province made five points:

And excellent supporting cast of heavy machinery and other large products. Develop supporting cast of heavy machinery, mining machinery and equipment for casting, water, electricity and petrochemical valves and marine stainless steel castings, Railway castings and fittings necessary equipment, wind power castings and other products.

Big automotive castings, building domestic infrastructure provides the most competitive production base of automobile castings. Big Yuncheng, Linfen, Jincheng, Taiyuan, Luliang automotive castings clusters, build domestic infrastructure provides the most competitive production base of automobile castings. Focus on developing the engine cylinder block, cylinder head, brake drums, wheel Yi, brakes, gear-housing, car axles and other automotive castings.

Strong cast pipe industry, building the largest production base of iron pipe. Precision Pipe focus on the development of urban construction, covers, supporting shaft, large diameter water supply and drainage of urban underground ductile iron pipe and fittings, all falling into the water and drainage series of ductile iron pipe and fittings.

Do fine based on mechanical, hydraulic, and assorted castings. Promote the use of international advanced manufacturing technology, supporting cast to do spinning and other products. Focus on developing generator cylinder block castings, castings and hydraulic parts, textile machinery and accessories supporting cast, reducer, engine body, machine tool accessories and other products.

Make special aluminum-magnesium alloy and other special castings. Relying on Foxconn, Jincheng to grace to magnesium, Taiyuan with Xiang, Minmetals Sheng Ying, Huaze Aluminum and Power and other enterprises to increase Chan Xueyan development and technological innovations, to make special aluminum-magnesium alloy castings specially in our province. Focus on the development of automobile, motorcycle, 3C products, aerospace, medical, military and other fields with aluminum-magnesium alloy castings.

The Jet JWBS-16 MK2 is intended for heavy work and has cast iron blade wheels, a super cast iron table which can tilt from -10° to +45°, a locking rip fence which is supported at the front and rear of the table and extends slightly beyond the cast iron table to give an excellent capacity on both sides of the blade. On the face of the rip fence is a point cutting attachment which is ideal for re-sawing. The mitre fence is ‘T’ slotted into the table for accuracy, safety and extended capacity. The blade is guided both above and below the table with micrometer-adjusted thrust and bearing rollers which give a positive support to the blade, resulting in a very good quality of cut and extended blade life. With fully interlocked doors, electro-mechanical motor brake and with easily accessible blade tension and tracking controls, this machine is for the professional workshop where an accurate bandsaw with good capacities can become a very popular machine with which to work. To move this machine around the workshop we recommend the purchase of the mobile base unit (Stock Number 708119). This additional base unit is easy to fit and allows the machine to be moved without fear of tipping the unit over or causing any damage to either the operator or the machine. NB A 20A supply is recommended when used with 240 volt supply. www.axminster.co.uk
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Terrestrial Trunked Radio – China Machined Parts – Metal casting

Description
The common mode of operation for them is in a group calling mode in which a single button push will connect the user to the users in a selected callgroup and/or a dispatcher. It is also possible for the terminal to act as a one-to-one walkie talkie but without the normal range limitation since the call still uses the network. If enabled by the Subscriber Management TETRA terminals can act as mobile phones (cell phones), with a full-duplex direct connection to other TETRA Users or the PSTN. Emergency buttons, provided on the terminals, enable the users to transmit emergency signals, to the dispatcher, overriding any other activity taking place at the same time.
TETRA uses Time Division Multiple Access (TDMA) with four user channels on one radio carrier and 25 kHz spacing between carriers. Both point-to-point and point-to-multipoint transfer can be used. Digital data transmission is also included in the standard though at a low data rate.
TETRA Mobile Stations (MS) can communicate Direct Mode or using Trunked infrastructure (Switching and Management Infrastructure or SwMI) made of TETRA Base Stations (TBS). As well as allowing direct communications in situations where network coverage is not available, Direct Mode or DMO also includes the possibility of using one (or a chain) of TETRA terminals as relays for a signal. This functionality is called DMO gateway (from DMO to TMO) or DMO Repeater (DMO to DMO). In Emergency situations this feature allows direct communications underground or in areas of bad coverage.
In addition to voice and dispatch services, the TETRA system supports several types of data communication. Status messages and Short Data Services (SDS) are provided over the system’s main control channel, while Packet Data or Circuit switched data communication uses specifically assigned traffic channels.
TETRA provides Authentication Mechanisms of Terminals towards Infrastructure and vice versa. For protection against eavesdropping, over the air encryption and end-to-end encryption is available. Advantages of TETRA
The main advantages of TETRA over other technologies (such as GSM) are:
the much lower frequency used gives longer range, which in turn permits very high levels of geographic coverage with a smaller number of transmitters, thus cutting infrastructure costs.
High spectral efficiency – 4 channels in 25 kHz and no guard bands, compared to GSM with 8 channels in 200 kHz and guard bands.
very fast call set-up – a one to many group call is generally set-up within 0.5 seconds (typical less than 250 msec for a single node call) compared with the many seconds (typically 7 to 10s) that are required for a GSM network.
Works at high speeds >400 km/h. TETRA was used during the French TGV train speed record on 3 April 2007 at 574.8 km/h.
the system contains several mechanisms, designed into the protocols and radio parameters, to ensure communication success even during overload situations (e.g. during major public events or disaster situations), thus calls will always get through unlike in cellular systems. The system also supports a range of emergency calling modes.
TETRA infrastructure is usually separate from (but connected to) that of the public (mobile) phone networks, resulting in (normally) no call charges for the system owners, substantially more diverse and resilient communications and it is easy to customise and integrate with data applications (vehicle location, GIS databases, dispatch systems etc).
unlike most cellular technologies, TETRA networks typically provide a number of fall-back modes such as the ability for a base station to process local calls. So called Mission Critical networks can be built with TETRA where all aspects are fail-safe/multiple-redundant.
in the absence of a network mobiles/portables can use ‘direct mode’ whereby they share channels directly (walkie-talkie mode).
gateway mode – where a single mobile with connection to the network can act as a relay for other nearby mobiles that are out of range of the infrastructure.
TETRA also provides a point-to-point function that traditional analogue emergency services radio systems did not provide. This enables users to have a one-to-one trunked ‘radio’ link between sets without the need for the direct involvement of a control room operator/dispatcher.
unlike the cellular technologies, which connect one subscriber to one other subscriber (one-to-one) then TETRA is built to do one-to-one, one-to-many and many-to-many. These operational modes are directly relevant to the public safety and professional users.
TETRA supports both air-interface encryption and End-to-end encryption
Rapid deployment (transportable) network solutions are available for disaster relief and temporary capacity provision.
Equipment is available from many suppliers around the world, thus providing the benefits of competition
Network solutions are available in both the older circuit-switched (telephone like) architectures and flat, IP architectures with soft (software) switches.
Further information is available from the TETRA Association (formerly TETRA MoU) and the standards can be downloaded for free from ETSI. Disadvantages of TETRA
Its main disadvantages are:
requires a linear amplifier to meet the stringent RF specifications that allow it to exist alongside other radio services.
handsets are more expensive than cellular (about 750 EUR in 2003, about 600 EUR in 2006). This is due to the more difficult technology, smaller economies of scale, and different business model (eg: need for security, high powers and robustness). However cheaper than main (PMR) *competitor technology APCO-16 where prices are >00 per handset. TETRA prices expected to fall further as far eastern manufacturers start production in 2007.
data transfer is efficient and long range (many km), but slow by modern standards at 7.2 kbit/s per timeslot (3.5 kbit/slot net packet data throughput), although up to 4 timeslots can be combined into a single data channel to achieve higher rates whilst still fitting into a single 25 kHz bandwidth channel. Latest version of standard supports 115.2 kbit/s in 25 kHz or up to 691.2 kbit/s in an expanded 150 kHz channel.
due to the pulsed nature of TDMA employed by the protocol and higher powers than cellular, handsets (only) can sometimes interfere with badly designed (usually old) or sensitive electronic devices such as broadcast (TV) receivers. This has prompted some concerns from users of sensitive devices such as heart pacemakers but there are no documented reports of problems even though used regularly by many ambulance crews. As a precaution, users of these equipments should take care with any RF transmitting equipment when used in close proximity (e.g. < 1 metre distance.) TETRA Usage
The TETRA-system is in use by the public sector in the following countries
Continent
Country
Name
Agency
Status
Asia
Pakistan
Ministry of Interior
Police
In use Nationwide
India
Military College of Telecommunication Engineering (MCTE)
Indian Army
In use since 2004 at Mhow, Indore, Madhya Pradesh
AD100.
Kerala Police.
In use by police – Trivandrum city.
Taiwan
[]http://zh.wikipedia.org/wiki/
Taiwan Railways Administration,Railway Police Bureau
In use.
Israel
Mountain Rose.
Israel Defense Forces (IDF).
In use by IDF, country-wide.
Hong Kong
EADS TETRA Terminals
2008 Beijing Olympics and Paralympic Games (Hong Kong Equestrian Event)
Used from July 2008 to October 2008
Hong Kong Fire Services Department
Fire Service, Ambulance
In use.
Hong Kong Police Force
Police
In use.
Mass Transit Railway (MTR)
Transport
In use.
Hong Kong International Airport (HKIA)
Transport
Live from Feb 2009
Macao
Melco-Crown Entertainment
Casino-Hotels: Altira (formerly Crown Macau), and City of Dreams
In use since 2007.
Foras de Segurana de Macau
All Emergency Services
In use.
Africa
Sudan
Ministry of Interior
Police
In use Nationwide
Europe
Belgium
A.S.T.R.I.D
Austria
Police, Fire, Ambulance, Local Train Company
In use in all states except Tyrol and Vorarlberg (still roll-out)
Britain
Airwave
Police, Fire, Ambulance, Armed Forces, Highways Agency
In use by police all over the country.
Denmark
SINE
Police, Fire, Ambulance
Nationwide roll-out in progress
Ireland
TETRA Ireland
Garda, Fire, Ambulance, Defence Forces, Civil Defence, Security of State services
Nation-wide roll-out network
Italy
Rete Interpolizie
Polizia di Stato (Italian State Police), the Carabinieri (Military Police), the Guardia di Finanza (Customs Police), the Polizia Penitenziaria (Prison Police) and for the Corpo Forestale Italiano (Italian Forest Brigades)
Roll-out
Finland
VIRVE
Police, Fire, Ambulance, Customs, Defence Forces, Border guard
Nation-wide network
HelenNet
Helsingin Energia (One of the largest energy companies in Finland), Security guards (Mostly at shopping malls, train/metro stations and trams), Helsinki’s public transport
In use.
Estonia
[[ ]]
Police, Fire, Ambulance, Customs
Roll-out
Greece
C4I
Police, Fire, Coast Guard
Attica region
OTE
Airport, Metro, Security, Transportation, Taxi, Utilities, etc
Nation-wide Public Network
Latvia
Ventamonjaks Serviss Ltd, Ventspils Oil & Gas
In use since 2007.
Netherlands
C2000
Police, Fire, Ambulance
Nation-wide network
Norway
Ndnett
Police, Fire, Ambulance, Search and Rescue
Roll-out
Morocco
ADM
Highway authority
Roll-out
Sweden
RAKEL
Police, Fire
Roll-out
Portugal
SIRESP
Police, Fire, Ambulance
Nation-wide Roll-out in use since 2007
Romania
STS (Special Telecommunications Service)
Police, Fire, Search&Rescue
Nation-wide
Middle East
United Arab Emirates
Nedaa
Police, emergency services, professional communications
Dubai, Sharjah, Ajman, Umm Al-Qaiwain, Ras Al-Khaimah, Fujairah operational
Polikom
Police, emergency services, professional communications
Abu Dhabi Radio Frequencies
In South America, TETRA uses frequencies:
Emergency Systems
Number
Frequency Pair (MHz)
Band 1
Band 2
1
380-383
390-393
2
383-385
393-395
Civil Systems
Number
Frequency Pair (MHz)
Band 1
Band 2
1
410-420
420-430
2
870-876
915-921
3
450-460
460-470
4
385-390
395-399.9 Radio aspects
To send information TETRA uses a digital modulation scheme known as /4 DQPSK, this is a form of phase shift keying. The symbol (baud) rate is 18,000 symbols per second, and each symbol maps to 2 bits, thus resulting in 36,000 bit/s gross. As a form of phase shift keying is used to transmit data during each burst, it would seem reasonable to expect the transmit power to be constant. However it is not. This is because the sidebands, which are essentially a repetition of the data in the main carrier’s modulation, are filtered off with a sharp filter so that unnecessary spectrum is not used up. This results in an amplitude modulation and is why TETRA requires linear amplifiers. The resulting ratio of peak to mean (rms) power is 3.65 dB. If non-linear (or not-linear enough) amplifiers are used, the sidebands re-appear and cause interference on adjacent channels. Commonly used techniques for achieving the necessary linearity include cartesian loops, and adaptive predistortion.
The base stations normally transmit continuously and (simultaneously) receive continuously from various mobiles – hence they are Frequency Division Duplex. TETRA also uses TDMA (see above). The mobiles normally only transmit on 1 slot/4 and receive on 1 slot/4 so they are both Time Division and Frequency Division Duplex.
Speech signals in TETRA are sampled at 8 kbit/s and then compressed with a vocoder using a technique called ACELP (Adaptive Code Excited Linear Prediction). This creates a data stream of 4.567 kbit/s. This data stream is error-protection encoded before transmission to allow correct decoding even in noisy (erroneous) channels. The data rate after coding is 7.2 kbit/s – the capacity of a single traffic slot when used 17/18 frames.
A single slot consists of 255 usable symbols, the remaining time is used up with synchronisation sequences and turning on/off etc. A single frame consists of 4 slots, and a multiframe (whose duration is 1.02 seconds) consists of 18 frames. Hyperframes also exist, but are mostly used for providing synchronisation to encryption algorithms.
The downlink (i.e. the output of the base station) is normally a continuous transmission consisting of either specific communications with mobile(s), synchronisation or other general broadcasts. All slots are usually filled with a burst even if idle (continuous mode). Although the system uses 18 frames per second only 17 of these are used for traffic channels, with the 18th frame reserved for signalling, Short Data Service messages (like SMS in GSM) or synchronisation. The frame structure in TETRA (17.65 frames per second = 18 frames in 1.02 seconds), consists of 18000 symbols/s / 255 symbols/slot / 4 slots/frame, and is the cause of the perceived “amplitude modulation” at 17 Hz and is especially apparent in mobiles/portables which only transmit on one slot/4. They use the remaining three slots to switch frequency to receive a burst from the base station two slots later and then return to their transmit frequency (TDMA). Cell Re-Selection (or Hand-over) in Images
RSSI SRT FRT Cell Limit (Propagation Delay Exceed)
This first representation demonstrates where the SRT (Slow Reselect Threshold) the FRT (Fast Reselect Threshold) and propagation Delay exceed parameters are most likely to be. These are represented in association with the decaying radio carrier as the distance increases from the TETRA Base Station.
From this illustration, these SRT and FRT triggering points are associated to the decaying radio signal strength of the respective cell carriers. The thresholds are situated so that the cell reselection procedures occur on time and assure communication continuity for on-going communication calls. Initial Cell Selection
Cell Initial Selection
The next diagram illustrates where a given TETRA radio Cell Initial Selection.
The initial cell selection is performed by procedures located in the MLE and in the MAC. When the cell selection is made, and possible registration is performed, the MS (mobile station) is said to be attached to the cell.
The mobile is allowed to initially select any suitable cell that has a positive C1 value, i .e. the received signal level is greater than the Minimum Rx Level for Access parameter.
The initial cell selection procedure shall ensure that the MS selects a cell in which it can reliably decode downlink data, i.e. on a main control channel (MCCH), and which has a high probability of uplink communication. The minimum conditions that shall have to be met are that C1 > 0. Access to the network shall be conditional on the successful selection of a cell.
At mobile switch on, the mobile makes its initial cell selection of one of the base stations, which indicates the initial exchanges at activation.
Refer to EN 300 392 2 16.3.1 Activation and control of underlying MLE Service
Note 18.5.12 Minimum RX access level
The minimum RX access level information element shall indicate the minimum received signal level required at the SwMI in a cell, either the serving cell or a neighbour cell as defined in table 18.24. Cell Improvable
Cell Improvable
The next diagram illustrates where a given TETRA radio cell becomes Improvable.
The serving cell becomes improvable when the following occurs:
The C1 of the serving cell is below the value defined in the radio network parameter cell reselection parameters, slow reselect threshold for a period of 5 seconds, and the C1 or C2 of a neighbour cell exceeds the C1 of the serving cell by the value defined in the radio network parameter cell reselection parameters, slow reselect hysteresis for a period of 5 seconds. Cell Usable
Cell Usable
The next diagram illustrates where a given TETRA radio cell becomes Usable.
A neighbour cell becomes radio usable when the cell has a downlink radio connection of sufficient quality.
The following conditions must be met in order to declare a neighbour cell radio usable:
The neighbour cell has a path loss parameter C1 or C2 that is greater than the following: (FAST_RESELECT_THRESHOLD+FAST_RESELECT_HYSTERISIS) for a period of 5 seconds, and the service level provided by the neighbour cell is higher than that of the serving cell. No successful cell reselection shall have taken place within the previous 15 seconds unless MM requests a cell reselection. The MS-MLE shall check the criterion for serving cell relinquishment as often as one neighbour cell is scanned or monitored.
The following conditions will cause the MS to rate the neighbour cell to have higher service level than the current serving cell:
The MS subscriber class is supported on the neighbour cell but not on the serving cell.
The neighbour cell is a priority cell and the serving cell is not.
The neighbour cell supports a service (that is, TETRA standard speech, packet data, or encryption) that is not supported by the serving cell and the MS requires that service to be available.
The cell service level indicates that the neighbour cell is less loaded than the serving cell. Cell Relinquishable (Abandonable)
Cell Relinquishable
The next diagram illustrates where a given TETRA radio cell becomes Relinquishable (Abandonable).
The serving cell becomes relinquishable when the following occurs: The C1 of the serving cell is below the value defined in the radio network parameter cell reselection parameters, fast reselect threshold, for a period of 5 seconds, and the C1 or C2 of a neighbour cell exceeds the C1 of the serving cell by the value defined in the radio network parameter cell reselection parameters, fast reselect hysteresis, for a period of 5 seconds.
No successful cell reselection shall have taken place within the previous 15 seconds unless MM (Mobility Management) requests a cell reselection. The MS-MLE shall check the criterion for serving cell relinquishment as often as one neighbour cell is scanned or monitored. Radio Down-link Failure
Radio Down-link Failure
When the FRT threshold is breached, the MS is in a situation where it is essential to relinquish (or abandon) the serving cell and obtain another of at least Usable quality. That is to say, the mobile station is aware that the radio signal is decaying rapidly, and must cell reselect rapidly, before communications are terminated because of radio link failure. When the mobile station radio-signal breaches the Rx Lev minimum the radio is no longer in a position to maintain acceptable communications for the user, and the radio link is broken.
Radio link failure: (C1 < 0). Using the suggested values, this would be satisfied with the Serving Cell Level below -105 dBm. Cell reselection procedures are then activated in order to find a suitable radio base station.
Infrastructure TETRA Parametres to be Verified
This table serves only as a guide.
Type of Radio Cover
Parametre
Distance in km
Type of Communication
City
< 4
< 8
Pedestrian / Metro
Sub-Urban
10 to 18
20 to 36
Bus / Train
Countryside
18 to 31
36 to 62
Inter Regional Train
In Air
> 32
> 64
In Flight A Virtual MMI for TETRA radio Terminals
Any given TETRA radio terminal using Java (J2ME /CLDC) based technology, provides the end user with the communication rights necessary to fulfill his or her work roll on any short duration assignment.
For Dexterity, flexibility, and evolution ability, the RATP radio engineering department, have chosen to use the open sources, Java language specification administered by Sun and the associated work groups in order to produce a transport application tool kit. RATP TETRA MMI
RATP-TETRA KVM- MMI
Service acquisition admits different authorised agents to establish communication channels between different services by calling the service identity, and without possessing the complete knowledge of the ISSI, GSSI, or any other TETRA related communication establishment numbering plan. Service acquisition is administered through a communication rights centralised service or roll allocation server, interfaced into the TETRA core network.
In summary, the RATP TETRA MMI aims are to:
Allow any given agent while in exercise, to exploit any given radio terminal without materiel constraint.
Provide specific transportation application software to the RATP end-user agents. (Service Acquisition , Fraud and Aggression control)
This transport application tool-kit has been produced successfully and with TETRA communication technology and assures for the RATP transport application requirements for the future mentioned hereafter.
The Home (Main) menu presents the end user with three possibilities:
a) Service Acquisition,
b) Status SDS,
c) End user parameters
Service Acquisition provides a means of virtually personalising the end user to any given radio terminal and onto TETRA network for the duration the end user conserves the terminal under his / her possession.
Status SDS provides the end user with a mechanism for generating a 440Hz repeating tone that signals a fraud occurrence to colleagues who are currently within the same (dynamic or static) Group Short Subscriber Identity GSSI or to a specific Individual Short Subscriber Identity, ISSI for the duration of the assignment ( an hour, a morning patrol or a given short period allocated to the assignment). The advantage being that each of the end users may attach themselves to any given terminal, and group for short durations without requiring any major reconfiguration by means of radio software programming tools. Similarly, the aggression feature functions, but with a higher tone frequency (880Hz), and with a quicker repetitious nature, so to highlight the urgency of the alert.
The Parameters tab provides an essential means to the terminal end-user allowing them to pre-configure the target (preprogrammed ISSI or GSSI ) destination communication number. With this pre-programmed destination number, the end-user shall liaise with the destination radio terminal or Roll Allocation Server, and may communicate, in the group, or into a dedicated server to which the service acquisition requests are received, preprocessed, and ultimately dispatched though the RATP TETRA core network. This simplifies the reconfiguration or recycling configuration process allowing flexibility on short assignments.
The Parameters tab also provides a means of selecting pre selected tones to match the work group requirements for the purposes of Fraud and Aggression Alerts. A possibility of selecting any given key available from the keypad to serve as an aggression or fraud quick key is also made possible though the transport application software tool kit. The RATP recommend using the Asterisk and the Hash keys for the Fraud and Aggression quick keys respectively. For the fraud and aggression tones the RATP also recommend using 440Hz slow repeating tone (blank space 500 milli-seconds) and 880Hz fast repeating tone (blank space 250 milli seconds) respectively.
The tone options are as follows: 440 Hz 620 Hz, 880Hz, 1060Hz.
The Parameters page on yet another tab provides an Aid or Help menu and finally, the last tab within parameters describes briefly the tool kit the version and the history of the transport application tool kit to date.
Refer also to: JSR-118,
Mobile Information Device Profile, JSR-37,
Wireless Messaging API, JSR120,
Connected Limited Device Configuration JSR-139
Technology for the Wireless Industry JTWI-185: See also
Rohill Provider of TETRA Communication Systems under TetraNode brand
Artevea Provider of TETRA Communication Systems under T-MATRIX brand
EADS Secure Networks, provider of TETRA Networks after it bought Nokia’s PMR business at 2005
Motorola provider of TETRA Networks under Dimetra IP brand
NXDN, a two-way digital radio standard with similar characteristics
P25, a TIA APCO standard used in North America References
^ ETSI EN 300 392-2 v3.2.1
^ http://www.tetra-association.com TETRA Association
^ http://www.eads.net/1024/en/dcs_pmr/products_services/tetra_terminals/tetra_terminals.html
^ http://www.artevea.com/casestudies-detail.php?type=case&id=10
^ http://mediacenter.motorola.com/content/Detail.aspx?ReleaseID=10788&NewsAreaID=2
^ http://www.artevea.com/casestudies-detail.php?type=case&id=12
^ http://www.selex-comms.com/internet/index.php?open0=5&open1=24&section=CORP&showentry=4421 Selex Communications
^ http://www.artevea.com/casestudies-detail.php?type=case&id=11 External links
Rohill TETRA
Artevea TETRA Communication System
EADS TETRA
Motorola Dimetra TETRA Products
A blog about TETRA Security and info
Report on the health effects of TETRA by NRPB
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Trunked radio systems
Central controller
Motorola systems: Type I Type II Type IIi Hybrid Type II SmartZone Type II SmartZone OmniLink iDEN
Other: APCO Project 16 APCO Project 25 EDACS EDACS Provoice MPT-1327 OpenSky TETRA TETRAPOL
Scan-based / distributed control
General Electric Mobile Radio: GE Marc V
Logic Trunked Radio: LTR Standard LTR Passport LTR Standard and Passport LTR MultiNet LTR-Net Categories: Trunked radio systems | Mobile telecommunications standards

Cast Iron Fireplaces, Bringing Elegance To Your Home

A home wouldn’t be complete without a stunning fireplace and there is nothing like a cast iron fireplace to enhance your living room, bringing warmth and elegance to your home. Hours are spent in front of a glowing fire during cold winter days and nights and it’s a wonderful feeling to sit in a warm cosy, comfortable room with an attractive fireplace as a centrepiece to your home.

A fireplace is responsible for the charisma and charm of a living room and is normally the main focus when entering a room. People often spend a lot of money in finding ways in which to improve their living room and create a warm and cosy ambiance but with a stunning fireplace and, in particular a cast iron fireplace, this is easily achievable.

As one of the most popular fireplaces on the market today, due to its exquisite and intricate designs and flexibility of being suitable for most family homes. They are very cost effective and long lasting and come in neautral colours such as black, grey and silver, so they are suitable for all types of décor, creating a traditional or even a modern look to your home. Cast iron fireplaces are practical and one of the benefits of owning a one is that it is suitable for either gas or even solid fuel and will create a warming and pleasurable appeal.

There is no doubt that cast iron fireplaces are not only cost effective but are also extremely attractive, boasting wonderful designs such as the Bolton Cast Iron suite which also offers a Henlow fire surround in Agean limestone and a granite hearth or the Pembroke, Edwardian or Amsterdam designs which combine a granite or slate hearth, often with a polished finish. With so much choice available, from the more Victorian and Georgian designs to the more contemporary and sophisticated designs, it’s hard not to find a Cast iron fireplace that would be ideal for your home.

Cast iron fireplaces have a long standing history. Benjamin Franklin discovered that most freestanding fireplaces lost much of their heat through their sides, so it was shortly after that when David Rittenhouse made improvements to Franklin’s design. The result in these changes also brought about the Franklin stove. By the late 1700s, iron freestanding fireplaces were also being used as stoves in various parts of the world. Wood or coal was burned to cook the evening meal but would also keep the room warm for many hours afterwards. This made them very efficient and extremely popular. Today’s modern freestanding and built in fireplaces are made from the finest iron material on the market.

Whatever design you choose, you will have the pleasure of owning a very fine fireplace and no matter what size room you have, you can create that wonderfully cosy feel to suit your home. It’s hardly surprising why cast iron fireplaces have now made such a huge come back and are so popular today.

Find More Grey Cast Iron Articles

Precious coral

Habitat

Red corals grow on rocky seabottom with low sedimentation, typically in dark environments–either in the depths or in dark caverns or crevices. The original species, C. rubrum, is found mainly in the Mediterranean Sea. It grows at depths from 10 to 300 m, although the shallower of these habitats have been largely depleted by harvesting. In the underwater caves of Alghero, Sardinia (the “Coral Riviera”) it grows at the depth of 4 m. The same species is also found at Atlantic sites near the Strait of Gibraltar and at the Cape Verde Islands. Other Corallium species are native to the western Pacific, notably around Japan (Corallium japonicum) and Taiwan; these occur at depths of 350 to 1500 m in areas with strong currents.

Anatomy

In common with other Gorgonacea, red corals have the shape of small leafless bushes and grow up to a meter in height. Their valuable skeleton is composed of intermeshed spicules of hard calcium carbonate, colored in shades of red by carotenoid pigments. In living specimens, the skeletal branches are overlaid with soft bright red integument, from which numerous retractable white polyps protrude. The polyps exhibit octameric radial symmetry.

Coral as a gemstone

Polished fragments of fake dyed red bamboo coral

Chinese coral sculpture

Non precious red dyed sponge coral earrings

The hard skeleton of red coral branches is naturally matte, but can be polished to a glassy shine. It exhibits a range of warm reddish pink colors from pale pink to deep red; the word coral is also used to name such colors. Owing to its intense and permanent coloration and glossiness, precious coral skeletons have been harvested since antiquity for decorative use. Coral jewelry has been found in ancient Egyptian and prehistoric European burials, and continues to be made to the present day.

Precious coral has relative density of 3.86 and hardness 3.5 on the Mohs scale. Due to its softness and opacity, coral is usually cut en cabochon, or used to make beads.

History of trade in coral

At the beginning of the Christian era, there was a great trade carried on in coral between the Mediterranean and India, where it was highly esteemed as a substance endowed with mysterious sacred properties. It is remarked by Pliny that, previous to the existence of the Indian demand, the Gauls were in the habit of using it for the ornamentation of their weapons of war and helmets; but in his day, so great was the Eastern demand, that it was very rarely seen even in the regions which produced it. Among the Romans branches of coral were hung around children’s necks to preserve them from danger, and the substance had many medicinal virtues attributed to it. A belief in its potency as a charm continued to be entertained throughout medieval times; and even early in the 20th century in Italy was worn as a preservative from the evil eye, and by females as a cure for sterility.

From the middle ages upwards the securing of the right to the coral fisheries on the African coasts was an object of considerable rivalry among the Mediterranean communities of Europe. Previous to the 16th century they were controlled by the Italian republics. For a short period the Tunisian fisheries were secured by Charles V to Spain; but the monopoly soon fell into the hands of the French, who held the right till the Revolutionary government in 1793 threw the trade open. For a short period (about 1806) the British government controlled the fisheries, but later returned to the hands of the French authorities. Previous to the French Revolution much of the coral trade centred in Marseilles; but since that period, both the procuring of the raw material and the working of it up into the various forms in which it is used became peculiarly Italian industries, centering largely in Naples, Rome and Genoa.

Coral in mythology

The origin of coral is explained in Greek mythology by the story of Perseus. Having petrified Cetus, the sea monster threatening Andromeda, Perseus placed Medusa’s head on the riverbank while he washed his hands. When he recovered her head, he saw that her blood had turned the seaweed (in some variants the reeds) into red coral. Thus, the Greek word for coral is ‘Gorgeia’, as Medusa was one of the three Gorgons.

Poseidon resided in a palace made of coral and gems, and Hephaestus first crafted his work from coral.

The Romans believed coral could protect children from harm, as well as cure wounds made by snakes and scorpions and diagnose diseases by changing colour.

Trivia

The two biogenic precious gemstones, coral and pearl, although drastically different in appearance, are chemically very similar. Both are mostly calcium carbonate deposited by marine invertebrates.

Another unrelated species, the Hawaiian black coral is sometimes used as an ornamental material. Its skeleton is not mineralized, consisting mostly of conchiolin.

In Vedic astrology red coral is associated with the planet Mars.

A branch of red coral figures prominently in the civic coat of arms of the town of Alghero, Italy.

References

^ a b c d “Corallium species”. ARKive. http://www.arkive.org/coral/Coral/corallium_more.html. Retrieved 2007-02-15. 

^ a b c “Gemstones: Coral”. http://www.gemstone.org/gem-by-gem/english/coral.html. Retrieved 2007-02-15. 

^ a b “Red Coral”. Marenostrum. http://marenostrum.org/vidamarina/animalia/invertebrados/cnidarios/corales/rojoi.htm. Retrieved 2007-02-15. 

^ “Jewelry Central”. http://www.jewelrycentral.com/Target_Coral.asp. Retrieved 2007-02-15. 

^  ”Coral”. Encyclopdia Britannica (11th ed.). 1911. 

^ “Passage from Ovid’s Metamorphoses about the origin of coral”. http://findarticles.com/p/articles/mi_m0422/is_2_81/ai_55174794/pg_34. Retrieved 2007-03-18. 

External links

www.arkive.org Photos of living red corals and skeletons (Accessed 02 February 2007)

International Colored Gemstone Association Extensive info on gemstone coral and jewelry photos (Accessed 02 February 2007)

American Gem Trade Association Information on coral as a gemstone (Accessed 02 February 2007)

Organic Gems: Red Coral Jewelry Photos of raw coral material and coral jewelry (Accessed 02 February 2007)

Mediterranean red coral: research team International Research Team on Mediterranean red coral (Accessed 15 March 2007)

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Jewellery

Forms

Anklet  Belt buckle  Belly chain   Bracelet  Brooch  Chatelaine  Crown  Cufflink  Earring  lapel pin  Necklace  Pendant  Ring  Tiara  Tie clip  Watch (pocket)

Making

People

Bench jeweler  Goldsmith  Jewelry designer  Lapidary  Watchmaker

Processes

Casting (centrifugal, lost-wax, vacuum)  Enameling  Engraving  Filigree  Metal clay  Plating  Polishing  Repouss and chasing  Soldering  Stonesetting  Wire wrapping

Tools

Draw plate  File  Hammer  Mandrel  Pliers

Materials

Precious metals

Gold  Palladium  Platinum  Rhodium  Silver

Precious metal alloys

Britannia silver  Colored gold  Crown gold  Electrum  Platinum sterling  Shakudo  Shibuichi  Sterling silver  Tumbaga

Base metals/alloys

Brass  Bronze  Copper  Kuromido  Pewter  Stainless steel  Titanium

Mineral gemstones

Aventurine  Agate  Alexandrite  Amethyst  Aquamarine  Carnelian  Citrine  Diamond  Emerald  Garnet  Jade  Jasper  Malachite  Lapis lazuli  Moonstone  Obsidian  Onyx  Opal  Peridot  Quartz  Ruby  Sapphire  Sodalite  Sunstone  Tanzanite  Tiger’s Eye  Topaz  Tourmaline

Organic gemstones

Amber  Copal  Coral  Jet  Pearl  Abalone

Terms

Carat (unit)  Carat (purity)  Finding  Millesimal fineness

Related topics: Body piercing  Fashion  Gemology  Metalworking  Wearable art

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Corals and coral reefs

Stony corals

Scleractinia  Hermatypic coral  Blue coral  Brain coral  Pillar coral  Staghorn coral  Table coral

Soft corals

Alcyonacea  Black coral  Bamboo coral  Organ pipe coral  Sea fans  Sea pens

Coral diseases

Coral bleaching  Black band disease  Skeletal eroding band  White band disease  White pox disease

Coral reefs

Atoll reef  Cay  Fringing reef  Microatoll  Coral reef fish  The Structure and Distribution of Coral Reefs

Coral regions

Deep water coral  Andros, Bahamas  Belize Barrier Reef  Coral Sea Islands  Coral Triangle  Great Barrier Reef  Maldives  New Caledonia Barrier Reef  Pulley Ridge  Raja Ampat Islands  Red Sea  Southeast Asian coral reefs

Protection

Coral reef protection  Project AWARE  Reef Check  Reef Ball  Coral Reef Alliance  International Society for Reef Studies

Other

Coral biology  Coral dermatitis  Coral (precious)  Coral rag  Coral sand  Coralline algae  Fire coral  Rugosa (extinct)  Tabulate (extinct)  Zooxanthella

Categories: Anthozoa | Gemstones

AC Refrigeration Compressors, Industrial Fans and Blowers, Packaged Chilling Units, Graded Castings, Ice Machines, HVACR Systems

The advancements in chemistry and science in the 19th century have added pace to the developments in the field of Heating Ventilation Air Conditioning and Refrigeration. Due to this technical breakthrough in HVACR field, a large number of air conditioning, air handling and refrigeration products have emerged in the market for various comfort and process applications. When it comes to the manufacturers of these HVACR products there are many but none can match the pioneer, ACCEL India. With four decades of experience in HVACR industry, ACCEL is an ISO 9001: 2000 certified organization that leads the race for manufacturing air handling, air conditioning and refrigeration equipment.

Air conditioning and Refrigeration equipment:
The equipments used for cooling purposes or temperature reduction purposes generally fall under the category of air conditioning and refrigeration. The refrigeration compressors and air conditioning compressors are the heart of the air conditioning and refrigeration equipments that provide air conditioning, heat pumping and refrigeration for large-scale facilities and equipment by compressing low-pressure, low-volume gas into high-pressure and high-temperature gas. Providing the ultimate benefits of high co-efficient of performance and low power consumption, our single stage air conditioning and refrigeration compressors are the compact and vibration free compressors used for comfort cooling, cold storage and marine and mobile applications. Our two stage air conditioning and refrigeration compressors fall under the category of low power consuming compressors for low temperature applications below -45 degrees like fisheries and dairies. Assembled on a compact rugged base frame, our preassembled factory tested chillers, condensers, compressors and motors are fully protected by reliable calibrated safety devices. Fitted with SMC compressors, our packaged chilling units or brine chilling units are the complete factory assembled units for central air conditioning, marine air conditioning and process cooling in chemical, pharmaceutical, textile industries. Our plate ice machines and flake ice machines are self contained and self sufficient plate ice makers that are available in capacities ranging from 5 to 300 tons.

Industrial fans and blowers:
Industrial fans and blowers are machines to provide a large flow of air or gas to various processes of many industries. This is achieved by rotating a number of blades connected to a hub and shaft. Our air screw fans, tube axial fans, vane axial fans, axial flow fans, bifurcator fans and roof ventilator fans constitute the best range of industrial fans for hot gas applications. ID fan, FD fan, coal mill fan, ESP fan, cooler fan, air slide blower, cool vent fan, nose cooling fan, bag filter fan, exhaust fan and supply fan constitute our dynamic list for centrifugal fans and blowers for dust loading applications.

Graded castings:
Castings are the finished objects generally made by pouring liquid metals into molds to be casted into desired shapes used in different applications in various industries. Equipped with world-class technologies, ACCEL foundry division produces various graded castings for various in-house and outside customer requirements. Our Spheroidal Graphite iron castings are the ductile iron castings with installed capacity of 2000 tonnes per annum used for various industrial purposes. Grey iron is generally brown colored iron which owes its color to the presence of graphite in it. The castings made of grey iron are available with us in grades of 25 and other standard grades for pharmaceutical and other industries. We also manufacture various types of alloy castings tailored as per customer requirements for the best use in machine tools, compressors, pumps and valves.

HVACR systems:
HVACR stands for Heating Ventilation Air Conditioning and Refrigeration. Having expertise in HVACR projects, we excel in designing various air conditioning and refrigeration plants meeting the material specifications as per naval standards & grades. Our highly qualified engineers and technicians with vast experience in erection, commissioning and testing are capable of designing industry’s best marine AC & R systems for marine air conditioning and refrigeration applications.

For all types of HVACR systems, air conditioning and air handling equipments visit http://www.accelindia.com.

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