In order to minimize the problem of autobody corrosion, steel sheets for automotive body panels have undergone enormous changes from the conventional cold rolled steel sheets to coated steel sheets.
As an answer to counter corrosion caused by road salt in countries of cold climate, various types of coated steel sheets were developed and used since the second half of 1970s.
Coated steel sheets which are used in automobiles must not only provide corrosion resistance but also satisfy to variety of other performance requirements like pres formability, weldability, phosphatibility and paintability.
For automotive skin panels the major car makers in North America and some in Europe use electro-galvanized (EG) sheets with comparatively heavy zinc coating. In contrast, car manufactures in Japan use mainly galvannealed (GA) steel sheets which have a zinc-iron alloy coating.
At present, the use of galvanized steel in automobile body in India is only around 7 percent while around 80 percent of cars manufactured for exports have galvanized sheet body. A survey reveals a good correlation between the defects in automotive body and the age of the vehicle. Body parts close to the road are most prone to defects such as blisters and surface rust. This survey also reasonably establishes that the conversion of car body panels manufactured in India from painted cold rolled steel to painted galvanized steel will significantly improve the corrosion performance. It is now a matter of time that increased use of GI/GA strips in car manufacturing in India becomes a reality.
Special features for an automotive CGL
These following equipment are required additionally by an automotive CGL over and above the other standard features like Double pass Payoff, Loopers, Welder, After Pot Cooling, Tension Leveling, Chemical Coater, Recoiling, etc. for a Conventional Galvanizing Line targeting construction & appliance markets:
1. Electrolytic Cleaning Section
2. Pickling Section after cleaning
3. Annealing Furnace with Heating, Soaking and Rapid Cooling Sections
Denne historien er fra August 2019-utgaven av Steel Insights.
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Denne historien er fra August 2019-utgaven av Steel Insights.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
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Steel's Net Zero mission
The country’s commitment to achieving Net Zero within a targeted timeframe will now propel its steel sector towards a sustainable future in line with global trends.
Fuel Price Hike, Supply Chain Disruption Hurt Festive Sales
Supply chain disruptions and fuel price hikes have hurt festive sales in a big way as most auto majors posted decline in sales in October.
Seaborne coking coal offers remain range-bound
Seaborne coking coal offers moved in a narrow range in October amid global supply tightness and healthy spot demand.
Global crude steel output down 8% in September
China manufactured 74 mt in September, fall of 21% y-o-y while India’s production went up by 7% to 10 mt.
MOIL embarks on expansion projects
“Even though our country is blessed with manganese ore reserves, we import 50% of the domestic requirement. We have to lower our import dependence and save precious foreign exchange.” Ram Chandra Prasad Singh, Steel Minister
Iron ore handled by major ports down 17% in H1
The 12 major Indian ports handled 27 mt of iron-ore during H1 of 2021, down by 17% from 33 mt recorded for the corresponding period of previous year.
Shrinking China output to boost India exports
“In the third quarter of 2021, the company actively responded to the pressure from external policies, such as production curtailment and dual control system on energy consumption and intensity, as well as coal resource shortage and surging prices.” Baoshan Iron and Steel Co Ltd
Indian Railways' iron-ore handling up 25% in H1
Indian Railways in April-September of 2021 (H1) transported 84 mt of iron ore, up by 25% over 67 mt during April-September 2020.
September crude steel production up 7.2% y-o-y
India’s crude steel production in September 2021 grew 7.2 percent to 9.547 million tons (mt) over September 2020 but was down by 3.2 percent from August 2021 output, provisional steel ministry data showed.
“Five enablers: way forward to sustainable cleaner steel”
Right and scalable technology, appropriate policy guidance by government, access to finance to fund transition, willingness of customers to pay for cleaner products and infrastructure for use of new technologies are the need of the hour for the sustainable and cleaner steel industry, according to Madhulika Sharma, Chief Corporate Sustainability, Tata Steel.
