Wednesday, May 19, 2010

Trade Regulations, Customs and Standards for USA

Trade Regulations, Customs and Standards

Import Tariffs
A. Customs Regulations, Tariff Rates, and Import Taxes
B. Customs Valuation
Import Requirements and Documentation
U.S. Export Controls
Temporary Entry
Labeling and Marking Requirements
Prohibited and Restricted Imports
Customs Regulations and Contact Information
Standards
Trade Agreements
Import Tariffs

Note: Customs and taxation procedures for Bosnia and Herzegovina have been undergoing significant changes due to the consolidation of all indirect taxation authority into one State-level Indirect Tax Administration (ITA).

A. Customs Regulations, Tariff Rates, and Import Taxes

1. Registration requirements for importing

Any domestic and foreign entities (physical and legal), registered for foreign trade activities may conduct such activities. The registration of requests for imports of goods is, in principle, not applied, with the exception of certain specific goods.

2. National tariffs

The Customs Tariff Nomenclature is based on the Harmonized Commodity Description and Coding System (HS). BiH nomenclature of goods is fully harmonized with the combined EU nomenclature.

Customs duties on all commodities imported into the customs territory of Bosnia and Herzegovina are paid ad valorem at rates of 0, 5, 10 and 15 percent. These rates apply to commodities originating from countries that have concluded an agreement with a Most Favored Nation (MFN) clause with Bosnia and Herzegovina, or from those countries that apply the same clause on the commodities originating from BiH. Upon BiH accession to WTO, MFN treatment will be granted to all WTO members.

In addition to ad valorem custom duty rates, an additional duty is paid on imports of certain agricultural products in a per-unit amount. This additional duty is charged on 852 of the total number of tariff headings (10,823), and the amounts range from 0.08 BAM/per unit to 6.00 BAM/per unit.

Preferential tariff measures, pursuant to Article 3 paragraph (c) of the Customs Tariff Law, may apply to goods from certain countries or groups of countries which have concluded an agreement on preferential treatment with BiH.

Free Trade Agreements (FTAs) have been concluded with Albania, Bulgaria, Croatia, Macedonia, Moldova, Romania, Serbia & Montenegro, and Turkey. These agreements are fully compatible with Article XXIV of the 1994 GATT and other WTO provisions on regional integration. As of June 2007, these FTAs were replaced by CEFTA (Central European Free Trade Agreement), which includes all aforementioned countries except Turkey, which is covered by a separate FTA - see the chapter on Investment Climate.

3. Tariff quotas, tariff exemptions

Tariff quotas - Articles 3 and 7 of the BiH Customs Tariff Law permit the introduction of tariff quotas as a special measure for certain tariff headings. Consequently, the BiH Council of Ministers (CoM) may approve imports of goods exempt from customs duties or at tariff rates lower than the duty set by the BiH Customs Tariff. The application of this measure is restricted to limits, and ceases when the stipulated limit or value of the quota is reached. Tariff quotas are only applied to raw materials imported at zero tariff for the meat-processing industry (as of June 2004).

Tariff exemptions and relief - Irrespective of tariff rates set by the Customs Tariff Law, some goods are exempt from customs duties under specific conditions. The following goods are exempt from customs duties:

- Equipment representing the investment of a foreign person, except passenger vehicles and entertainment and gaming machines;

- Goods for military and police forces in the entities that are fully donor financed;

- Goods for reconstruction projects in BIH.

4. Other duties and charges

Irrespective of the customs duty which is paid on all commodities imported into the customs territory of BiH at the rates stipulated in the Customs tariff, the Law on Customs Policy, and the Law on Foreign Trade Policy, there are other regulations prescribing or allowing imposition of other taxes and charges.

Customs record keeping - Article 13 paragraph (b) of the Law on Customs Policy prescribes a charge of 1 percent of the customs value on imported goods for customs record keeping.

While BiH plans to maintain the charge, it will be restricted to the cost of services rendered and it will be brought into conformity with Article VIII of the 1994 GATT when BiH accedes to WTO, in line with an agreed transitional period.

Seasonal duty - Article 19 paragraph 7 of the Law on Customs Policy allows for imposition of a seasonal duty. Accordingly, in addition to the tariff rates in force, the BiH Council of Ministers, after consulting the entities, may introduce a seasonal duty on non-processed agricultural products for a set period of time. The seasonal duty has never been applied.

Antidumping and Countervailing Duties - Goods imported to BIH at prices below their normal value or subsidized in some way may be subject to antidumping and countervailing duties, in accordance with BiH law.

Fees for Inspection of Goods - Article 7, paragraph 3 of the Law on Foreign Trade Policy requires sanitary, veterinary, phyto-sanitary and ecological inspections of certain imported goods. Fees for these inspections are set by the Law on Administrative Fees and are approximately equal to the value of the service performed, in line with Article VIII of GATT.

5. Application of internal taxes on imports

Value Added Tax (VAT) – As of January 1, 2006, Bosnia and Herzegovina introduced a Value Added Tax (VAT) at a flat rate of 17 percent that is levied on all imported goods.

Excise tax - The excise tax is paid only on certain goods at the moment of their release for free circulation. The excise tax is applied identically to domestic and imported goods.

The goods for which an excise tax is levied are: oil derivatives, tobacco, beverages, alcoholic drinks, beer and wine and coffee.

6. Rules of origin

Rules of origin are set out in Articles 20 - 23 of the Law on Customs Policy. This Law distinguishes between non-preferential and preferential origins. BiH has not concluded an agreement on preferential origin with the U.S.

Non-preferential origin - The Law stipulates that goods originating from a country are those wholly obtained or produced in that country. Goods whose production involved more than one country shall be deemed to originate in the country where they underwent their last substantial and economically justified processing or finishing in a company equipped for that purpose and resulting in the manufacture of a new product or representing an important stage of manufacture.

Preferential origin of goods - Article 23 of the Law on Customs Policy prescribes the rules to be applied for preferential trade, i.e. the conditions goods need to fulfill in order to benefit from the preferential measures referred to in Article 19, paragraph 4 (c) and (d) of the Law.

B. Customs Valuation

Articles 24 to 32 of the Law on Customs Policy establish procedures for the determination of the customs value of goods.

Pursuant to Article 25 of the Law on Customs Policy, the customs value of imported goods is the transaction value, i.e. the price actually paid or payable for the goods when sold for exports to the customs territory of BiH.

The system of customs valuation in the Law on Customs Policy is fully compatible with WTO rules.

Import Requirements and Documentation

All goods imported into the customs territory of Bosnia and Herzegovina are subject to customs procedures contained in the Law on Customs policy, which apply uniformly throughout the customs territory of BiH. Imports must be accompanied by a customs declaration, filled out in one of the three official languages of BiH (Bosnian, Serbian or Croatian), submitted by the person named on the waybill or an authorized representative. The declaration must be accompanied by any relevant documents (invoice, shipping documents, quality control certificates). The customs office may inspect the goods and take samples to determine that the goods correspond to the information on the customs declaration. Once the customs office determines the amount of customs duty, the importer is required to obtain a guarantee covering the customs duty with the Customs Authority in the form of a cash deposit or a bank guarantee. The goods cannot be placed in circulation until customs duties have been paid or the payment has been guaranteed.

Bill of Lading: May be direct or to order. Mail and parcel shipments require postal documentation in place of bills of lading. Packages containing merchandise for which the senders are to receive payment must enclose the original invoice in the package (marked “Original Invoice”) and the wrapper of the package must be marked to indicate that the original invoice is enclosed. Senders are recommended to post a signed copy of the invoice giving notice to the addressees that the packages are en route. Air cargo shipments require airway bills with the number of copies issued based on requirements of the importer and the airline.

Certificate of Origin: Certificates of origin should be issued in a minimum of two copies (the certifying organization will require an additional notarized file copy) made out by a reliable authority or agency duly authorized for that purpose by the country of issue. Certificates of origin are not required for imports for long-term production ventures with foreign partners, for the purchase of capital goods for investment projects abroad and for the return of goods to Bosnia and Herzegovina, or for imports without payment of equivalent value.

Commercial Invoice: There is no prescribed format. Invoices should be issued in a minimum of two copies; additional copies may be requested. They must contain the usual particulars, including a full description of goods, marks and numbers, gross and net weights, number of packages, country of origin, plus any information that must be furnished to conform to contract.

Insurance Certificate: Normal commercial practices. Follow importer’s and/or insurance company’s instructions/advice.

Packing List: Not mandatory, but its use will facilitate clearance of goods.

Pre-shipment inspection: May be requested by importer.

Pro-Forma Invoice: May be requested by importer.

U.S. Shipper’s Export Declaration (SED): Required if value is more than USD 2,500 (USD 500 for shipments through the US postal system). SEDs are required for all shipments requiring an export license.

U.S. Export Controls

More information on US export controls to Bosnia and Herzegovina and general guidelines can be found at the Bureau of Industry and Security website (http://www.bis.doc.gov/licensing/ExportingBasics.htm).

In general, here is the summary of steps to take to process your export:

Ensure that your export is under U.S. Department of Commerce jurisdiction.
Classify your item by reviewing the Commerce Control List.
If your item is classified by an Export Control Classification Number (ECCN), identify the Reasons for Control on the Commerce Control List.
Cross-reference the ECCN Controls against the Commerce Country Chart to see if a license is required. If yes, determine if a License Exception is available before applying for a license.
Ensure that no proscribed end-users or end-uses are involved with your export transaction. If proscribed end-users or end-uses are involved, determine if you can proceed with the transaction or must apply for a license.
Export your item using the correct ECCN and the appropriate symbol (e.g., NLR, license exception, or license number and expiration date) on your export documentation (e.g., Shipper’s Export Declaration).
Temporary Entry

Goods temporarily entering BiH may be fully or partially free of customs duties and must not undergo any changes except for the nominal loss of value due to use. The maximum period for temporary entry is 12 months. The full list of goods that can be imported under this regime is provided in the Law on Customs Policy.

Labeling and Marking Requirements

Labels must contain the following information: name of the product, full address of the importer and the country of origin, net quantity/weight/volume, ingredients, manner of storage (transport, use, or maintenance), and pertinent consumer warnings. Technically complex products must be accompanied by instructions on usage, manufacturer specifications, a list of authorized maintenance persons/businesses, warranty information, warranty period, and other applicable data. All information must be translated into the languages of BiH and affixed to (or accompanying) the product before it is put on the market.

Prohibited and Restricted Imports

In accordance with Article 6, paragraph 2 of the Law on Foreign Trade Policy, for reasons of public safety and protection of human health and lives, the following types of imports are restricted:

Passenger cars older than seven years;
Cargo vehicles older than ten years;
Buses older than ten years;
Trailers for cargo vehicles older than ten years;
Used tires.
In accordance with obligations from international trade agreements, the CoM may ban imports, exports, or transit of certain goods through BiH or set conditions for imports, exports, or transport of such goods in transit in order to prevent danger to human lives, health and the environment.

Customs Regulations and Contact Information

Uprava za Indirektno Oporezivanje Bosne i Hercegovine - Indirect Taxation Administration of Bosnia and Herzegovina

Phone: +387-(0)51-335-494 Fax: +387-(0)51-335-101
Bana Lazarevica bb
Banja Luka, 78000 Bosnia and Herzegovina
http://www.uino.gov.ba/

Standards

Overview
Standards Organizations
Conformity Assessment
Product Certification
Accreditation
Publication of Technical Regulations
Labeling and Marking
Contacts
Overview

After the breakup of Yugoslavia, BiH inherited 11,183 Yugoslav standards and by-laws (known as “JUS” standards). Currently there are around 10,391 JUS standards in force. Identical regulations and standards are applied to both domestic and imported goods, regardless of the country of origin.

As of January 1, 2007 the former Institute for Standardization, Metrology and Intellectually Property of BiH was broken into three separate Institutes:

Institute for Standardization
Institute for Metrology
Institute for Intellectual Property Rights (“IPR Institute”)
BiH standards are designated as the BAS Standard. BiH is a member of the following international organizations for standardization:

ISO International Organization for Standardization;
IEC International Electro-technical Commission;
CEN European Committee for Standardization;
CENELEC European Committee for Electro-technical Standardization;
ETSI European Telecommunications Standards;
Standards Organizations

Institute for Standardization
Institute for Metrology
Institute for Intellectual Property Rights (“IPR Institute”)
Testing/Conformity Assessment

The Institute for Standardization is the main conformity assessment body in BiH. There are other testing organizations in BiH; a list of these institutions can be obtained from the Institute.

Product Certification

Product certification is required in order to make sure that the product has undergone appropriate testing and that it conforms to relevant regulations. There are no existing Mutual Recognition Agreements with U.S. organizations.

Accreditation

The Accreditation Institute of BiH is the main institution for accrediting testing organizations in the country.

Publication of Technical Regulations

The Institute for Standardization of BiH publishes a bulletin of standards. Technical regulations are published in: the Official Gazette of BiH, Official Gazette of FBiH, and the Official Gazette of RS. U.S. companies can comment directly to the Institute.

Labeling and Marking

Labels must contain the following information: name of the product, full address of the importer and the country of origin, net quantity/weight/volume, ingredients, manner of storage (transport, use or maintenance), and pertinent consumer warnings. Technically complex products must be accompanied by instructions on usage, the manufacturer’s specifications, a list of authorized maintenance persons/businesses, warranty information, warranty period, and other applicable data. All information must be translated into the languages of Bosnia and Herzegovina and be affixed to (or accompany) the product before it is put on the market.

Contacts

Institute for Standardization

Mr. Goran Tesanovic, Director

Hamdije Cemerlica 2/7

71000 Sarajevo, Bosnia and Herzegovina

Phone: +387-33-652-781 Fax: +387-33-652-757



Institute for Metrology

Mr. Esad Tuzovic, Director

Dolina 6

71000 Sarajevo, Bosnia and Herzegovina

Phone: +387-33-207-015



Institute for Intellectual Property Rights

Ms. Lidija Vignjevic, Director

Kralja Petra Kresimira IV 8a

88000 Mostar, Bosnia and Herzegovina

Phone: +387-36-334-381



Accreditation Institute of BiH

Mr. Zarko Petrovic, Director

Hamdije Cemerlica 2/7

71000 Sarajevo, Bosnia and Herzegovina

Phone: +387-33-721-310

Trade Agreements

In December 2006, Bosnia and Herzegovina signed the Central European Free Trade Agreement (CEFTA) which became fully operational in November 2007. The regional trade group includes Albania, Bosnia and Herzegovina, Croatia, Macedonia, Serbia, Montenegro, Kosovo and Moldova. In June 2008, Bosnia and Herzegovina signed the Stabilization and Association Agreement (SAA) with the European Union which is an important step towards the EU membership. The most important part of the SAA is the establishment of a free trade zone between Bosnia and Herzegovina and the European Union, implying the mutual abolishment of all custom tariffs and quantity limitations in mutual exchange of goods from BiH and the EU. The SAA should encourage further development of competitiveness among the country’s exporters and increase investments and employment. With the start of 2009, import tariffs have been eliminated for 11,000 products that BiH imports from the EU. For products such as cosmetics, tractors, motorcycles, furniture, major appliances, electronic equipment, computers and tools tariffs were cut by 50 per cent immediately upon signing, and from January 1 they have been eliminated completely.

mobiles

Ray T65-2529
Nokia 3110 + 1GB-2239
LG KP265- 2449
Micromax Q3- 3219
Motorola EM30 Cherry-3059
Samsung C3010-2949
Samsung B2100-2649

INDIA Budget 2010-11

Budget 2010-11: Summary of Major Amendment in Custom duty Laws
Feb 26, 2010 Budget 2010


Note: (a) “Customs Duty” means the customs duty levied under the Customs Act, 1962.
(b) “CVD” means the Additional Duty of Customs levied under section 3 of the Customs Tariff Act, 1975. Changes come into effect immediately unless otherwise specified.
Major proposals about customs duties are the following:
A. PETROLEUM
1) Customs duty on crude petroleum is being increased from Nil to 5%.
2) Customs duty on Motor Spirit (petrol) and HSD (diesel) is being increased from 2.5% to 7.5%.
3) Customs duty on some other specified petroleum products is being increased from 5% to 10%.
B. PRECIOUS METALS
1) Customs duty on serially numbered gold bars (other than tola bars) and gold coins is being increased from Rs.200 per 10 gram to Rs.300 per 10 gram.
2) Customs duty on other forms of gold is being increased from Rs.500 per 10 gram to Rs.750 per 10 gram.
3) Customs duty on silver is being increased from Rs.1000 per kg to Rs.1500 per kg.
4) Customs duty on platinum is being increased from Rs.200 per 10 gram to Rs.300 per 10 gram.
The above change in rates would also be applicable when gold, silver and platinum (including ornaments) are imported as personal baggage.
C. ADDITIONAL DUTY OF CUSTOMS OF 4 % (SPECIAL CVD)
Goods imported in pre-packaged form and intended for retail sale and certain specified goods namely, ready-made garments, mobile phones and watches are being provided an outright exemption from additional duty of customs of 4%. In addition, outright exemption from this duty is also being provided to Carbon Black Feedstock, waste paper and paper scrap.
The existing exemption by way of refund would continue on other items.
D. FOOD/AGRO PROCESSING
1) Project imports status is being granted to the initial setting up or substantial expansion of, a cold storage, cold room (including farm pre-coolers) for preservation or storage or an industrial unit for processing of agricultural, apiary, horticultural, dairy, poultry, aquatic & marine produce and meat. These projects would attract concessional rate of basic customs duty of 5%.
2) Project imports status is being granted to installation of Mechanized Handling Systems & Pallet Racking Systems, in mandis or warehouses for food grains and sugar, with concessional rate of basic customs duty of 5%. Such systems are also being exempted from additional duty of customs (CVD) and special additional duty of customs.
3) Truck Refrigeration units for the manufacture of refrigerated vans/trucks are being fully exempted from basic customs duty. Such units are already exempt from excise duty.
4) Basic customs duty is being reduced from 7.5% to 5% on specified agricultural machinery such as paddy transplanter, laser land leveler, cotton picker, reaper-cum-binder, straw or fodder balers, sugarcane harvesters, track used for manufacture of track-type combine harvester etc.
E. AGRICULTURE/HORTICULTURE
1) Basic customs duty on long pepper is being reduced from 70% to 30%.
2) Basic customs duty on ‘asafoetida’ (heeng) is being reduced from 30% to 20%.
3) Full exemption from basic customs duty is being provided to bio-polymer/bio-plastics (HS Code 39139090) used for
manufacture of bio-degradable agro mulching films, nursery plantation & flower pots.
F. CAPITAL GOODS
1) Mono Rail Projects for urban transport are being granted project imports status under Heading No. 98 01 and would accordingly attract concessional rate of 5% basic customs duty.
2) Tunnel Boring machine for hydro-electric power projects is being fully exempted from basic customs duty with Nil CVD.
3) Concessional rate of customs duty of 5% presently available upto 06.07.2010 on specified machinery for tea, coffee and rubber plantation is being extended upto 31.03.2011. Excise duty exemption is also being re-introduced on these items upto 31 .03.2011.
4) Specified road construction machinery items are presently fully exempt from customs duty subject to specified conditions. Sale or disposal of such machinery items at depreciated value is being allowed on payment of customs duties on depreciated value at the rates applicable at the time of import subject to specified conditions.
G. CONCESSIONS TO ENVIRONMENT-FRIENDLY ITEMS
1) Full exemption from basic customs duty and special additional duty of customs is being extended to specified parts namely, batteries including battery chargers, electric motors and AC or DC motor controllers imported for manufacturing all categories of electrical vehicles including cars, two wheelers and three wheelers (like Soleckshaw). These parts will attract CVD of 4%. The concession is subject to actual user condition. This concession will be available till 31 .03.2013.
2) A concessional rate of basic customs duty of 5% is being provided to machinery items, instruments, appliances required for initial setting up of solar power generation projects or facilities. These items have been exempted from CVD also by way of excise duty exemption provided to them.
3) Ground source heat pump (for geo-thermal energy applications) is being fully exempted from basic customs duty and special additional duty of customs.
H. HEALTH SECTOR
1) At present, medical equipments attract varying rates of customs duty and are spread over many lists. This multiplicity of rates is being done away with and now all medical equipments (with some exceptions) will attract 5% basic customs duty, 4% CVD/excise duty and Nil special additional duty of customs [i.e. effective duty of 9.2%].
2) Parts required for the manufacture and accessories of medical equipment will also attract 5% concessional basic customs duty with Nil special CVD.
3) Concessional customs duty available to spares for the maintenance of medical equipment is being withdrawn except in specified cases.
4) Full exemption from basic customs duty and CVD/excise duty is being retained for specified medical devices (exempt by description) as well as for assistive devices, rehabilitation aids and other goods for disabled (List 41).
5) Cobalt-chrome alloys, special grade stainless steel etc. for the manufacture of orthopaedic implants are being exempted from basic customs duty subject to actual user condition.
I. ELECTRONICS HARDWARE
1) Battery chargers and hands-free headphones are the basic accessories of mobile phones. Full exemption from basic customs duty and CVD presently available for parts, components, accessories for manufacturing of mobile handsets including cellular phones and parts thereof is being extended to parts for the manufacture of battery chargers and hands-free headphones also.
2) Full exemption from 4% special additional duty of customs presently available upto 06.07.2010 on parts, components and accessories for manufacture of mobile handsets including cellular phones, parts thereof (except accessories) is being extended to parts of two specified accessories also upto 31.03.2011.
3) Basic customs duty is being reduced from 10% to 5% on magnetrons of upto 1,000 kw for the manufacture of microwave ovens.
4) Full exemption from customs duty is being extended to additional specified capital goods and raw materials for the manufacture of electronic hardware.
J. ENTERTAINMENT/MEDIA
1) Films for exhibition are imported on cinematographic films or digital media. Digital masters/Stampers of films are also imported for duplication and distribution of CD/DVDs. It is being provided that customs duty would now be charged only on the value of the carrier medium and the customs duty on the balance value will be exempt.
2) Similar tax treatment, as provided to films above, is being extended to music and gaming software (other than pre-packaged form) for retail sale imported on digital media for duplication. Pre-packaged Movies, Music and Games (meant for use with gaming consoles) will continue to be charged to import duties on value determined in terms of the provisions of the Customs Act.
3) Promotional material like trailors, making of films etc. imported free of cost in the form of electronic promotion kits (EPK)/ Betacams are being fully exempted from basic customs duty and CVD.
4) Project imports status is being accorded to ‘Setting up of Digital Head End’ with 5% concessional basic customs duty and Nil special additional duty of customs.
K. GOLD REFINING
Gold ore and concentrate are being fully exempted from basic customs duty and special additional duty of customs. They will, however, be chargeable to CVD @ Rs.140 per 10 gram of gold content. This duty structure is subject to actual user condition.
L. EXPORT PROMOTION
1) Basic customs duty on Rhodium is being reduced from 10% to 2%.
2) The current limit of Rs. 1 lakh per annum for duty free import of samples is being enhanced to Rs. 3 lakh per annum
3) At present specified components, raw materials and accessories for the manufacture of sports goods are exempt from basic customs duty. Some additional items are being added to the list of exemption.
M. ELECTRICAL ENERGY
At present, Electrical energy is fully exempt from customs duty. Electrical energy supplied from a Special Economic Zone to the Domestic Tariff Area and non – processing areas of SEZ would now attract duty of 16% ad valorem + Nil Special CVD. This change is being made retrospectively w.e.f. 26th June, 2009. Exemption on supplies or imports of electrical energy, other than the above, would continue.
N. AMENDMENTS IN CUSTOMS ACT, 1962
Section 127 dealing with Settlement Commission is being amended so as to restore certain provisions as they obtained prior to the enactment of the Finance Bill, 2007. Accordingly, the prohibition on filing of applications for the settlement of cases where an assessee admits short-levy in respect of goods not included in the entry made under the said Act. (i.e. cases of misdeclaration, suppression etc.) is being removed. Similarly, the restriction that an assessee may seek only one-time settlement is also being relaxed. The Commission is being empowered to extend the time limit of nine months for disposal of applications by another three months, for reasons to be recorded in writing.
O. AMENDMENTS IN CUSTOMS TARIFF ACT, 1975
1) Section 3 of the Customs Tariff Act is being amended to provide that the value of the imported goods for the purpose of charging CVD in respect of goods chargeable to excise duty on the basis of Maximum Retail Sale Price under Medicinal and Toilet Preparations (Excise Duties) Act, 1955 shall be the retail sale price declared on such imported goods less the amount of abatement, if any. This change will come into effect on enactment of the Finance Bill.
2) Consequent upon insertion of a new tariff item covering filter cigarettes of length not exceeding 60 mm and other changes in the schedule to the Central Excise Tariff Act, similar change is being carried out in heading 2402 with the new tariff item attracting customs duty of 30% ad valorem.
3) In Chapter 27, sub-heading 2712 20 and the tariff items 2712 20 10 and 2712 20 90 are being substituted by 2712 2000 covering ‘Paraffin Wax containing by weight less than 0.75% of oil’. Further, tariff item 2712 90 40 covering ‘Paraffin wax containing by weight 0.75% and more of oil’ is being inserted.


Read more: http://www.taxguru.in/budget-2010/budget-2010-11-summary-of-major-amendment-in-custom-duty-laws.html#ixzz0oP2gjxGT

Monday, May 3, 2010

Material Science -Crystallography

Material Science- Hot working

Hot working


In materials science, hot working refers to processes wheremetals are plastically deformed above their recrystallizationtemperature. Being above the recrystallization temperature allows the material to recrystallize during deformation. This is important because recrystallization keeps the materials fromstrain hardening, which ultimately keeps the yield strengthand hardness low and ductility high.[1] This contrasts withcold working.

Contents

[hide]

[edit]Temperature

The lower limit of the hot working temperature is determined by its recrystallization temperature. As a guideline, the lower limit of the hot working temperature of a material is 0.6 times its melting temperature(on an absolute temperature scale). The upper limit for hot working is determined by various factors, such as: excessive oxidation, grain growth, or an undesirable phase transformation. In practice materials are usually heated to the upper limit first to keep forming forces as low as possible and to maximize the amount of time available to hot work the workpiece.[1]

The most important aspect of any hot working process is controlling the temperature of the workpiece. Of 90% of the energy imparted into the workpiece is converted into heat. Therefore, if the deformation process is quick enough the temperature of the workpiece should rise, however, this does not usually happen in practice. Most of the heat is lost through the surface of the workpiece into the cooler tooling. This causes temperature gradients in the workpiece, usually due to non-uniform cross-sections where the thinner sections are cooler than the thicker sections. Ultimately, this can lead to cracking in the cooler, less ductile surfaces. One way to minimize the problem is to heat the tooling. The hotter the tooling the less heat lost to it, but as the tooling temperature rises, the tool life decreases. Therefore the tooling temperature must be compromised; commonly, hot working tooling is heated to 500–850 °F (325–450 °C).[2]

Lower limit hot working temperature for various metals[1]
MetalTemperature
TinRoom temperature
Steel2,000 °F (1,090 °C)
Tungsten4,000 °F (2,200 °C)

[edit]Advantages & disadvantages

The advantages are:[1]

  • Decrease in yield strength, therefore it is easier to work and uses less energy or force
  • Increase in ductility
  • Elevated temperatures increase diffusion which can remove or reduce chemical inhomogeneities
  • Pores may reduce in size or close completely during deformation
  • In steel, the weak, ductile, face-centered-cubic austenite microstructure is deformed instead of the strong body-centered-cubic ferrite microstructure found at lower temperatures

Usually the initial workpiece that is hot worked was originally cast. The microstructure of cast items does not optimize the engineering properties, from a microstructure standpoint. Hot working improve the engineering properties of the workpiece because it replaces the microstructure with one that has fine spherical shaped grains. These grains increase the strength, ductility, and toughness of the material.[2]

The engineering properties can also be improved by reorienting the inclusions (impurities). In the cast state the inclusions are randomly oriented, which, when intersecting the surface, can be a propagation point for cracks. When the material is hot worked the inclusions tend to flow with the contour of the surface, creating stringers. As a whole the strings create a flow structure, where the properties areanisotropic (different based on direction). With the stringers oriented parallel to the surface it strengthens the workpiece, especially with respect to fracturing. The stringers act as "crack-arrestors" because the crack will want to propagate through the stringer and not along it.[2]

The disadvantages are:[1]

  • Undesirable reactions between the metal and the surrounding atmosphere (scaling or rapid oxidation of the workpiece)
  • Less precise tolerances due to thermal contraction and warping from uneven cooling
  • Grain structure may vary throughout the metal for various reasons
  • Requires a heating unit of some kind such as a gas or diesel furnace or an induction heater, which can be very expensive

[edit]Processes

[edit]References

[edit]Notes

  1. ^ a b c d e Degarmo, p. 373.
  2. ^ a b c Degarmo, p. 374.

[edit]Bibliography

  • Degarmo, E. Paul; Black, J T.; Kohser, Ronald A. (2003), Materials and Processes in Manufacturing(9th ed.), Wiley, ISBN 0-471-65653-4.

Sunday, May 2, 2010

Absorption refrigerator

Absorption refrigerator


From Wikipedia, the free encyclopedia

The absorption refrigerator is a refrigerator that uses a heat source (e.g., solar, kerosene-fueled flame) to provide the energy needed to drive the cooling system. Absorption refrigerators are a popular alternative to regular compressor refrigerators where electricity is unreliable, costly, or unavailable, where noise from the compressor is problematic, or where surplus heat is available (e.g., from turbine exhausts or industrial processes). Absorption refrigerators powered by heat from the combustion of liquefied petroleum gas are often used for food storage in recreational vehicles.

Both absorption and compressor refrigerators use a refrigerant with a very low (less than 0 °F/−18 °C)boiling point. In both types, when this refrigerant evaporates or boils, it takes some heat away with it, providing the cooling effect. The main difference between the two types is the way the refrigerant is changed from a gas back into a liquid so that the cycle can repeat. A compressor refrigerator uses an electrically-powered compressor to increase the pressure on the gas, and then condenses the hot high pressure gas back to a liquid by heat exchange with a coolant (usually air). Once the high pressure gas has cooled, it passes through a pressure release valve which drops the refrigerant temperature to below freezing. An absorption refrigerator changes the gas back into a liquid using a different method that needs only heat, and has no moving parts. The other difference between the two types is the refrigerant used. Compressor refrigerators typically use an HCFC, while absorption refrigerators typically useammonia.

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[edit]Principles

Absorptive refrigeration uses a source of heat to provide the energy needed to drive the cooling process. The most common use is in commercial climate control and cooling of machinery. Absorptive refrigeration is also used to air-condition buildings using the waste heat from a gas turbine or water heater. The process is very efficient, since the gas turbine produces electricity, hot water and air-conditioning (see Trigeneration).

The basic thermodynamic process is not a conventional thermodynamic cooling process based onCharles' law. Instead, it is based on evaporation carrying heat, in the form of faster-moving (hotter)molecules, from one material to another material that preferentially absorbs hot molecules.

A familiar example is human sweating. The water in sweat evaporates and is "absorbed" into air, carrying away heat from the body. However, absorptive refrigerators differ in that they regenerate their coolants in a closed cycle, while people need to keep replacing their lost water (evaporated sweat) through drinking.

Labeled photo of a domestic absorption refrigerator.

The classic gas absorption refrigerator sends liquid ammoniainto a hydrogen gas. The liquid ammonia evaporates in the presence of hydrogen gas, providing the cooling. The now-gaseous ammonia is sent into a container holding water, which absorbs the ammonia. The water-ammonia solution is then directed past a heater, which boils ammonia gas out of the water-ammonia solution. The ammonia gas is then condensed into a liquid. The liquid ammonia is then sent back through the hydrogen gas, completing the cycle.

A similar system, common in large commercial plants, uses a solution of lithium bromide salt and water. Water under low pressure is evaporated from the coils that are being chilled. The water is absorbed by a lithium bromide/water solution. The water is driven off the lithium bromide solution using heat.

Adsorption chillers are a different approach to achieving air conditioning and process cooling. adsorption chillers are driven by hot water rather than from large amounts of electricity like conventional air conditioners. This hot water may come from any number of industrial sources. There are no CFCs or freons, no lithium bromide, and no ammonia. By replacing the corrosive salt desiccant with a benign silica gel, adsorption chillers significantly reduce maintenance and upkeep costs

Another variant uses air, water, and a salt water solution. As shown in the figure below, warm moist air is passed through a sprayed solution of salt water. The spray lowers the humidity. The less humid warm air is then passed through an evaporative cooler which cools and re-humidifies. Humidity is removed from the cooled air with another spray of salt solution. The salt solution is regenerated by heating it under low pressure, causing water to evaporate. The water evaporated from the salt solution is re-condensed, and rerouted back to the evaporative cooler.

Absorptive refrigeration.svg

[edit]Process

A single-pressure absorption refrigerator uses three substances: ammonia, hydrogen gas, and water, whereas large industrial units generally use only two: a refrigerant such as ammonia, and an absorbent such as water (with an expansion valve and pump, not described here). Normally, ammonia is a gas at room temperature (with a boiling point of -33 °C), but the system is pressurized to the point that the ammonia is a liquid at room temperature.

The cooling cycle starts at the evaporator, where liquefied anhydrous ammonia enters. ('Anhydrous' means there is no water in the ammonia, which is critical for exploiting its sub-zero boiling point.) The "evaporator" contains another gas (in this case, hydrogen), whose presence lowers the partial pressureof the ammonia in that part of the system. The total pressure in the system is still the same, but now not all of the pressure is being exerted by ammonia, as much of it is due to the pressure of the hydrogen. Ammonia doesn't react with hydrogen - the hydrogen is there solely to take up space - creating a void that still has the same pressure as the rest of the system, but not in the form of ammonia. Per Dalton's law, the ammonia behaves only in response to the proportion of the pressure represented by the ammonia, as if there was a vacuum and the hydrogen wasn't there. Because a substance's boiling point changes with pressure, the lowered partial pressure of ammonia changes the ammonia's boiling point, bringing it low enough that it can now boil below room temperature, as though it weren't under the pressure of the system in the first place. When it boils, it takes some heat away with it from the evaporator - which produces the "cold" desired in the refrigerator.

The next step is separating the gaseous ammonia-hydrogen mixture. Separation from the hydrogen is simple, and this is where the "absorber" comes in. Ammonia readily mixes with water, and hydrogen does not. The absorber is simply a downhill run of tubes in which the mixture of gases counterflows upwards in contact with water trickling down. At the top of the flow, with most of the ammonia gone into solution there, the gas is mainly hydrogen, free to return to the evaporator, while at the bottom of the flow, the dissolved AND gaseous ammonia concentrations are highest respectively, which is in accordance with the principle of a counterflow absorber, and now the solution is ready for entry to the boiler.

At this point in the cycle, the ammonia-water solution is not usable for refrigeration, as the mixture won't boil at a low enough temperature to be usable as a refrigerant. This is where the heat from the flame comes in. When the right amount of heat is applied to the mixture, the ammonia bubbles out. This phase is called the "generator" phase. The ammonia isn't quite dry yet - the bubbles contain gas but they're made of water, so the pipe twists and turns and contains a few minor obstacles that pop the bubbles so the gas can move on. The water that results from the bubbles isn't bad - it takes care of another need, and that is the circulation of water through the previous absorption step. Because that water has risen a bit while it was bubbling upwards, the flow of that water falling back down due to gravity can be used for this purpose. The maze that makes the ammonia gas go one way and the bubble water go the other is called the "separator".

The next step is the condenser. The condenser is a sort of heat sink or heat exchanger that cools the hot ammonia gas back down to room temperature. Because of the pressure and the purity of the gas (there is no hydrogen or water here), the ammonia condenses back into a liquid, and at that point, it's suitable as a refrigerant and the cycle starts over again.

[edit]History

Absorption cooling was invented by the French scientist Ferdinand Carré in 1858.[1] The original design used water and sulfuric acid.

In 1922 Baltzar von Platen and Carl Munters, while they were still students at the Royal Institute of Technology in Stockholm, Sweden, enhanced the principle with a 3 fluids configuration. This "Platen-Munters" design can operate without a pump.

Commercial production began in 1923 by the newly formed company AB Arctic, which was bought byElectrolux in 1925. In the 60s the absorption refrigeration sees a renaissance due to the substantial demand for refrigerators for caravans. AB Electrolux establishes a subsidiary in the U.S. – Dometic Sales Corporation. The company markets refrigerators for caravans and other recreation equipment under the Dometic brand. In 2001 Electrolux sells most of its Leisure Products product line to the venture-capital company EQT. The Dometic Group is created.

In 1926 Albert Einstein and his former student Leó Szilárd proposed an alternative design known asEinstein refrigerator[2].

In 2007, Adam Grosser presented his research of a new, very small, "intermittent absorption" refrigeration system for use in third world countries at the TED Conference. The refrigerator is a small unit placed over a campfire, that can later be used to cool 3 gallons of water to just above freezing for 24 hours in a 30 degree Celsius environment.[3]

[edit]See also

[edit]References

  1. ^ Eric Granryd & Björn Palm, Refrigerating engineering, Stockholm Royal Institute of Technology, 2005, see chap. 4-3
  2. ^ "US Patent 1781541".
  3. ^ "Adam Grosser and his sustainable fridge". TED. Retrieved 2010-04-18.

[edit]External links