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www.nipponsteel.com Steel Sheet Steel Sheets for Vitreous Enameling SteelSteel Sheets Sheets for for Vitreous Vitreous Enameling Enameling 2-6-1 Marunouchi, Chiyoda-ku,Tokyo 100-8071 Japan U046en_02_202004pU046en_02_202004f Tel: +81-3-6867-4111 © 2019, 2020 NIPPON STEEL CORPORATION NIPPON STEEL's Introduction Steel Sheets for Vitreous Enameling Manufacturing Processes Vitreous enamel is made by coating metal surface with glass. The compound material com- Table of Contents bines the properties of metal, such as high strength and excellent workability, with the char- Introduction acteristics of glass, such as corrosion resistance, chemical resistance, wear resistance, and Manufacturing Processes 1 visual appeal. Vitreous enamel has a long history, and the origin of industrial vitreous enamel- In addition to the high strength and excellent workability of cold-rolled steel sheets, steel sheets for vitreous enameling need to satisfy addi- ing is said to date back to the 17th century. Features 2 tional customer requirements such as higher adhesion strength of vitreous enamel, higher fishscaling resistance, and better enamel finish. Vitreous enamel is applied to not only kitchen utensils like pots, kettles and bathtubs but all- Product Performance 3 For this reason, in manufacturing steel sheets for vitreous enameling, the composition of the molten metal is controlled to an optimum level so containers used in the chemical and medical fields, sanitary wares, chemical machineries, and decarburized in the secondary refining process, and the temperature of the steel strip is precisely controlled in the hot rolling process Examples of Applications 4 building materials, and various components used in the energy field (such as heat exchanger and the continuous annealing process. Standards (Excerpted) 6 elements installed at electric power plants). Among relatively recent applications are cooking range housings and trays. Product Size Range 8 Since 1965, NIPPON STEEL has been manufacturing steel sheets for vitreous enameling, Precautions 10 which will be processed into vitreous enameled products downstream. Packaging and Labeling 12 ■ Our Steel Sheets for Vitreous Enameling Manufacturing Processes In order to not only improve the level of our quality that satisfies customers, but also to pro- Limestone pose additional values to them, NIPPON STEEL has been continuously improving the quality of our existing products and developing new products. One of our long-term research and Iron Ore Sintering Plant development themes was to make steel sheets with workability and enamelability at the Pig Iron Converter same time. We are pleased to share with you that NIPPON STEEL has successfully devel- oped the steel sheets for vitreous enameling that meet these two conflicting requirements. Blast Furnace Continuous Casting Coal Coking Plant These steel sheets are currently tested and used by an increasing number of customers. Secondary Refining Since we are confident that our steel sheets for vitreous enameling will live up to your expec- tations, we would like you to try the new products. Reheating Furnace Hot Rolling Mill Pickling Line Home-Use Vitreous Enameled Products (Gas Ovens and Microwave Ovens) Design Cleanliness Notice: While every effort has been made to ensure the Cold Rolling Mill Continuous Annealing Line Cold-Rolled Coil Stain accuracy of the information contained within Excellent Visual Appeal this publication, the use of the information is at Workability Resistance the reader’s risk and no warranty is implied or expressed by NIPPON STEEL CORPORATION with respect to the use of the information con- tained herein. The information in this publication Weather is subject to change or modification without Scratch Resistance ~Features of Vitreous Resistance notice. Please contact the NIPPON STEEL Enameled Products~ CORPORATION office for the latest information. Please refrain from unauthorized reproduction Heat Chemical or copying of the contents of this publication. Resistance Resistance The names of our products and services shown in this publication are trademarks or registered Wear Resistance Resistance to trademarks of NIPPON STEEL CORPORA- Seasonings TION, affiliated companies, or third parties Corrosion Resistance granting rights to NIPPON STEEL CORPORA- Sulfuric Acid Resistance, TION or affiliated companies. Other productor Hydrochloric Acid Resistance, service names shown may be trademarks or Alkali Resistance registered trademarks of their respective own- ers. Heat Exchangers and Other Equipment Converter Hot Rolling 1 NIPPON STEEL's NIPPON STEEL's Steel Sheets for Vitreous Enameling Features Steel Sheets for Vitreous Enameling Product Performance mprehensive Technic L's Co al Cap STEE abil N ities 1 Excellent Fishscaling Resistance PPO NI Our steel sheets have higher hydrogen storage capacity, preventing fishscaling from occurring in the vitreous enamel ■ Comparison of Fishscaling Resistance ● “Metallurgical Technology and Product Development Capacity” coating layer. The steel sheets coated on both sides with vitreous enamel Fishscaling H The effect of hydrogen ● “Process Development Solutions and Technologies” H 100 produce a similar effect. H Better absorption sites in the steel sheet doubled ● “Proposals for Application and Processing Technologies” → 80 shscaling resistance. Vitreous H Enamel Hydrogen Layer Accumulation 60 el Sh H H 40 EL's Ste eets for H Hydrogen H STE Vit Steel ON re Fishscaling Resistance PP ou Sheet H 20 f NI s E H o n H H H ← s am Worse re e 0 tu li a ng Our Material Ti-containing Steel Fe Our Steel Sheets for Figure 1: Fishscaling Resistance (Internal Data) Better Other Raw Material Vitreous Enameling → (Continuous-annealed (NSCSPP, NSCSPF, Ti-containing Steel) NSCSPN) 2 Other Raw Materials Excellent Durability Workability ■ Durability Comparison (Open-coil Annealed When applied to heat exchanger elements that are exposed to corrosive Market Needs Low-carbon Steel) ← environments, these steel sheets exhibit excellent durability. Better Poorer → Poorer← Enamelability →Better One of the features of our steel sheets for vitreous enameling is excellence in both workability and enamelability (excellent shscaling resistance, fewer defects in vitreous enamel coating layers, such as air bubbles, black Durability spots, and blisters, and excellent coating adhesion). Worse← Our Material Ti-containing Steel Vitreous Enameled Elements Proposals to Our Customers Figure 2: Durability Comparison (Internal Data) ● Streamlined ● Cost Reductions ● High Quality & High ● Manufacturing Processes Performance Reduced thicknesses of vitreous enamel layers ● Improved productivity ● Improved visual attractiveness ● Use of inexpensive frits ● Elimination of some existing ● Improved design exibility ● Improved yields processes 3 Low Earing Characteristics ■ Comparison of Earing Characteristics Our materials are made from ultra low carbon steel, exhibiting 0.6 sufficiently low earing characteristics. Worse RL + RC △R= -R45 ！ → 0.5 2 TIPS Why are steel sheets used as the base material for vitreous enameled products? 0.4 ） - 0.3 （ R The metals that can be used as the base material for vitreous enameled products are steel, cast iron, stainless steel, aluminum, copper, gold, △ and silver. Of these metals, steel is most commonly used for vitreous enameled products. One of the reasons is that steel sheets are excellent 0.2 in workability while having a moderate level of strength at the same time. In addition, the base metal used for vitreous enameled products should satisfy the following requirements. ← 0.1 1) The temperature suited for vitreous enameling should be lower than the melting point of the base metal. Better 2) The base metal must not deform significantly at the temperature suited for vitreous enameling. 0 3) The base metal must not generate large quantities of gas at the temperature suited for vitreous enameling. Our Material Ti-containing Steel 4) At the temperature suited for vitreous enameling, the base metal should get oxidized moderately so that the metal and the enamel tightly adhere to each other. Figure 3: Earing Characteristics (Internal Data) Our NSCSPF Ti-containing Steel Iron (steel sheet) was the metal that satisfied all of these requirements. 2 3 NIPPON STEEL's Steel Sheets for Vitreous Enameling Examples of Applications ■ Guidelines for Material Grade Selection by Application Major Applications JIS Designation NIPPON STEEL Standards Type of Forming Equipment Name Part Name Boards and the like White boards, sign boards, billboards, traffic signs SPPC,SPPD,SPPE NSCSPP1 General forming Building materials Building panels Heat exchangers Vitreous enameled elements Heating devices Top board of stove heaters and the like NSCSPP2 Stretch forming Ovens Cooktops NSCSPP3 Gas ranges Manifolds, side panels ■ Household Appliances Microwave ovens Trays NSCSPP4 Extra stretch forming This grade is recommended when you find it extremely difficult to form one of the above-mentioned products NSCSPN1·2 Drawing Heat exchangers Vitreous enameled elements No applicable NSCSPF1 Deep drawing Washing machines Dewatering bins JIS standards Water heaters Water heater tanks Toilet equipment Sanitary wares Ovens Oven side and inner cavity panels, bottom doors NSCSPF2 Cooking equipment Fryers Extra deep drawing NSCSPF3 Bathtubs Bathtubs Washing stands Sink bowls Drum-type washing machines, washing & drying machines Top boards Kitchen utensils Pots and kettles Bathtubs, Building Panels *The information contained in this table only provides guidelines
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