304 Stainless Steel Coil

304 Stainless Steel Coil

304 stainless steel coil is a low carbon, molybdenum bearing, austenitic stainless steel coil. Its chemistry features a minimum of 18% chromium and 8% nickel.

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These grade stainless steel coils are used for its corrosion resistance to many chemical corrodents, in addition to having good mechanical properties. The corrosion resistance of grade 304 stainless steel makes it ideal for food processing equipment and surgical instruments. It has superior formability and weld ability when compared to other grades of stainless steel.

304 Stainless Steel Coil Specifications

Product Name304 stainless steel coilGrades304/EN 1./SUS304HardnessSoft, Hard, Half Hard, Quarter Hard, Spring Hard as customer’s requirementsThickness0.02mm-6.0mmWidth1.0mm-mmEdgeSlit/MillQuantity Tolerance±10%Paper Core Internal DiameterØ500mm paper core, special internal diameter core and without paper core on customer requestSurface FinishNO.1/2B/2D/BA/HL/Brushed/6K/8K Mirror,etcPackagingWooden Pallet/Wooden CasePayment Terms30% TT deposit and 70% balance before shipment, 100% LC at sightDelivery Time5-7 working daysMOQ200KgsShipping PortShanghai/Ningbo portSampleThe sample of 304 stainless steel coil is available

304 Stainless Steel Coil Chemical Compositions

The chemical components of grade 304 stainless steel coil is summarized in the following table:

GradeStandardCSiMnPSCrNiMo304ASTM A240≤0.07≤0.75≤2.00≤0.045≤0..00-20.008.00-11.00–

304 Stainless Steel Coil Mechanical Properties

GradeEN GradeYield Strength Rp0.2(N/mm²)Tensile Strength Rm(N/mm²)HardnessVickers Hardness(HV)Elongation A50%.≥205≥520Annealed≥150≥40

How About 304 Stainless Steel Coil Production Process?

Most people don’t know how the 304 stainless steel coils are made, instead, they always see a lot of stainless steel coils in steel plants or industrial fields, but the truth is making 304 stainless steel coils is not easy than you imagined.

Basically, there are following steps for 304 stainless steel coils production.

304 Stainless Steel Coil: The Ultimate Guide

304 stainless steel coil is also used for components that are exposed to high temperatures or aggressive corrosive environments such as condensers, heat exchangers and furnace parts where oxidation resistance is required.

So enjoy the read...

What are 304 stainless steel coils?

304 stainless steel coil is a type of austenitic stainless steel with a minimum of 18% chromium, 8% nickel, and a maximum of 0.08% carbon.

It has excellent corrosion resistance in many environments, including fresh water, seawater, wastewater, acids and alkalies. It can be used for food processing and handling equipment such as tanks and heat exchangers.

These coils are made from annealed and pickled sheet, which gives them their ability to be shaped into any number of products. 304 stainless steel is an excellent choice for use in harsh environments where corrosion resistance is needed. This type of steel has a high resistance to rusting and oxidation, making it perfect for outdoor applications such as fencing or railings. It also has good resistance to pitting and crevice corrosion, which makes it a strong choice for marine environments.

304 stainless steel is often used in the medical industry because of its resistance to many different chemicals and its durability under high levels of heat. This makes it ideal for use in surgical instruments and other items that come into contact with human blood or bodily fluids. It can also be used in food processing equipment because it does not leach ions into food products as some other metals do.

What are the applications that 304 stainless steel coils can be used?

304 stainless steel coils can be used in a wide range of applications, including:

1.Food and beverage processing
The food industry uses 304 stainless steel coils to manufacture equipment like water heaters, boilers and tanks.

2.Healthcare equipment
Hospitals use 304 stainless steel coils to make a variety of medical equipment, including surgical tables, bedpans and incubators for newborns.

3.Industrial machinery
Manufacturers of industrial machinery rely on 304 stainless steel coils for parts such as valves and pumps in their products.

4.Construction equipment
Building contractors use 304 stainless steel coils to make weatherproofing materials that protect buildings from rain and snow while they are under construction or renovation.

Features of 304 stainless steel coils

304 stainless steel coils features:

1. 304 stainless steel coils is high strength, good toughness and wear resistance, corrosion resistance and thermal conductivity;

2. 304 stainless steel coils has a high temperature resistance (up to 870 degrees);

3. 304 stainless steel coils has good anti-oxidation ability and can be used in many occasions;

4. 304 stainless steel coils is widely used in all kinds of industries such as food, chemical industry and metallurgy, etc;

5. The price of 304 stainless steel coils is not expensive than other grades, but the price will rise rapidly when the demand for it increases.

What are 304 stainless steel coils surface finish?

Through different processing methods of cold rolling and surface reprocessing after rolling, the surface finish of 304 stainless steel coils can have different types.

The surface processing of stainless steel coils have NO.1, 2B, No. 4, HL, No. 6, No. 8, BA, TR hard, Rerolled bright 2H, polishing bright and other surface finishes, etc.

• NO.1: No. 1 surface refers to the surface obtained by heat treatment and pickling after hot rolling of the stainless steel strip. It is to remove the black oxide scale produced during hot rolling and heat treatment by pickling or similar treatment methods. This is No. 1 surface processing. The No.1 surface is silvery white and matt. Mainly used in heat-resistant and corrosion-resistant industries that do not require surface gloss, such as alcohol industry, chemical industry and large containers.
• 2B: The surface of 2B is different from the 2D surface in that it is smoothed with a smooth roller, so it is brighter than the 2D surface. The surface roughness Ra value measured by the instrument is 0.1～0.5μm, which is the most common processing type. This kind of stainless steel strip surface is the most versatile, suitable for general purposes, which is widely used in the chemical, paper, petroleum, medical and other industries, and can also be used as a building curtain wall.
• TR Hard Finish: TR stainless steel is also called hard steel. Its representative steel grades are 304 and 301, they are used for products that require high strength and hardness, such as railway vehicles, conveyor belts, springs and gaskets. The principle is to use the work hardening characteristics of austenitic stainless steel to increase the strength and hardness of the steel plate by cold working methods such as rolling. The hard material uses a few percent to several tens of percent of the mild rolling to replace the mild flatness of the 2B base surface, and no annealing is carried out after rolling. Therefore, the TR hard surface of the hard material is the rolled after cold rolling surface.
• Rerolled Bright 2H: After the rolling process. the stainless steel strips will be processed bright annealing. The strip can be fast cooled by the the continuous annealing line. The traveling speed of the stainless steel strip on the line is around 60m~80m/min. After this step, the surface finish will be 2H rerolled bright.
• No.4: The surface of No. 4 is a fine polished surface finish that is brighter than the surface of No. 3. It is also obtained by polishing the stainless steel cold-rolled stainless steel plate with 2 D or 2 B surface as the base and polishing with abrasive belt with a grain size of 150-180# Machined surface. The surface roughness Ra value measured by the instrument is 0.2～1.5μm. NO.4 surface is widely used in restaurant and kitchen equipment, medical equipment, architectural decoration, containers, etc.
• HL: HL surface is commonly called hairline finish. Japanese JIS standard stipulates that 150-240# abrasive belt is used to polish the continuous hairline-like abrasive surface obtained. In China’s GB standard, the regulations are rather vague. HL surface finish is mostly used for building decoration such as elevators, escalators, and facades.
• No.6: The surface of No. 6 is based on the surface of No. 4 and is further polished with a Tampico brush or abrasive material with a particle size of W63 specified by GB standard. This surface has a good metallic luster and soft performance. The reflection is weak and does not reflect the image. Due to this good property, it is very suitable for making building curtain walls and building fringe decorations, and also widely used as kitchen utensils.
• BA: BA is the surface obtained by bright heat treatment after cold rolling. Bright heat treatment is annealing under a protective atmosphere that guarantees that the surface is not oxidized to preserve the gloss of the cold-rolled surface, and then use a high-precision smoothing roll for light leveling to improve the surface brightness. This surface is close to a mirror finish, and the surface roughness Ra value measured by the instrument is 0.05-0.1μm. BA surface has a wide range of uses and can be used as kitchen utensils, household appliances, medical equipment, auto parts and decorations.
• No.8: No.8 is a mirror-finished surface with the highest reflectivity without abrasive grains. The stainless steel deep processing industry also calls as 8K plates. Generally, BA materials are used as raw materials for mirror finishing only through grinding and polishing. After mirror finishing, the surface is artistic, so it is mostly used in building entrance decoration and interior decoration.

What are 304 stainless steel coils edges?

Mill edge is a non-trimmed edge appearance after hot or cold rolling and annealing/pickling process. It usually leaved an irregular pinhole line on the edge side around 10mm to 15mm.

Slit/slitting edge means we will trim irregular pinhole line on our slitting machine.

For more information, please visit 304 stainless steel coil for architectural use.

How to buy 304 stainless steel coil from China?

Stainless steel coil is widely used in the field of industry and construction, and it has a bright future in the market.

As we know, stainless steel coil is made by rolling and drawing the steel strip so that it will become a coil with a circular cross section and different diameter.

There are many factors influencing the quality of stainless steel coils, such as production process, material selection and processing technology.

Therefore, if you want to buy stainless steel coils at lower price with high quality and good service from China suppliers, you need to know how to buy stainless steel coils from China firstly.

First of all, you should choose a reliable supplier who can provide good quality 304 stainless steel coils products at competitive prices. Then you can negotiate with them on price and other terms until reaching an agreement.

Secondly, you need to check whether they have advanced production equipment or not because if they do not have advanced equipment for producing various kinds of coils including stainless steel coils or if their production capacity is limited then it would be difficult for them to supply high quality products at competitive prices all year round.

Thirdly, it is better to visit their factory by yourself and check the production line and warehouse by yourself. It will be great if you can check their production process and production equipment. Because it is very important for you to know how they control the quality from process till delivery.

What is the standard sea packaging of 304 stainless steel coil?

• Standard export sea packaging:
  Waterproof Paper Winding+PVC Film+Strap Banding+Wooden Pallet or Wooden Case;
• Customized packaging as your request (Logo or other contents accepted to be printed on the packaging);
• Other special packaging will be designed as customer’s request;
  Eye to wall and eye to sky are both available;
• By International Express: DHL/UPS/FEDEX/EMS and our own express line;
• By air or By sea;
• Shipping port: Shanghai, Ningbo or as your request.

Grade 304 is a standard "18/8" stainless. It is the most versatile and most widely used stainless steel available, even though a wide range of alternatives are available; and has excellent forming and welding characteristics. The balanced austenitic structure of Grade 304 enables it to be severely deep drawn without intermediate annealing. This means that this grade steel is dominant in the manufacture of drawn stainless parts such as sinks, hollow-ware and saucepans. For these applications, it is common to use special "304DDQ" (Deep Drawing Quality) variants. Grade 304 can be readily braked or roll-formed into a variety of components for applications in the industrial, architectural, and transportation fields. It also has outstanding welding characteristics. Post-weld annealing is not required when welding thin sections.

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Grade 304L, the low carbon version of 304, does not require post-weld annealing and is therefore extensively used in heavy gauge components (over about 6mm). Grade 304H with its higher carbon content is used in applications at elevated temperatures. The austenitic structure also gives these grades excellent toughness, even down to cryogenic temperatures.

Key Properties

These properties are specified for flat rolled product (plate, sheet, and coil) in ASTM A240/A240M. Similar but not necessarily identical properties are specified for other products such as pipe and bar in their respective specifications.

Composition

Table 1. Typical composition ranges for 304-grade stainless steel

Grade C Mn Si P S Cr Mo Ni N 304 min.
max. -
0.08 -
2.0 -
0.75 -
0.045 -
0.030 18.0
20.0 - 8.0
10.5 -
0.10 304L min.
max. -
0.030 -
2.0 -
0.75 -
0.045 -
0.030 18.0
20.0 - 8.0
12.0 -
0.10 304H min.
max. 0.04
0.10 -
2.0 -
0.75 -0.045 -
0.030 18.0
20.0 - 8.0
10.5 -

Mechanical Properties

Table 2. Typical mechanical properties of 304-grade stainless steel

Grade Tensile Strength (MPa) min Yield Strength 0.2% Proof (MPa) min Elongation (% in 50 mm) min Hardness Rockwell B (HR B) max Brinell (HB) max 304 515 205 40 92 201 304L 485 170 40 92 201 304H 515 205 40 92 201

304H also requires a grain size of ASTM No 7 or coarser.

Physical Properties

Table 3. Typical physical properties of 304-grade stainless steel in the annealed condition

Grade Density (kg/m3) Elastic Modulus (GPa) Mean Coefficient of Thermal Expansion (μm/m/°C) Thermal Conductivity (W/m.K) Specific Heat 0-100 °C (J/kg.K) Electrical Resistivity (nΩ.m) 0-100 °C 0-315 °C 0-538 °C at 100 °C at 500 °C 304/L/H 193 17.2 17.8 18.4 16.2 21.5 500 720

Grade Specification Comparison

Table 4. Approximate Grade specifications for 304-grade stainless steel

Grade UNS No Old British Euronorm Swedish SS Japanese JIS BS En No Name 304 S 304S31 58E 1. X5CrNi18-10 SUS 304 304L S 304S11 - 1. X2CrNi19-11 SUS 304L 304H S 304S51 - 1. X6CrNi18-11 - -

These comparisons are approximate only. The list is intended as a comparison of functionally similar materials, not as a schedule of contractual equivalents. If exact equivalents are needed original specifications must be consulted.

Possible Alternative Grades

Table 5. Possible alternative grades to 304-grade stainless steel

Grade Why it might be chosen instead of 304 301L A higher work hardening rate grade is required for certain roll-formed or stretch formed components. 302HQ Lower work hardening rate is needed for cold forging of screws, bolts, and rivets. 303 Higher machinability needed, and the lower corrosion resistance, formability, and weldability are acceptable. 316 Higher resistance to pitting and crevice corrosion is required, in chloride environments 321 Better resistance to temperatures of around 600-900 °C is needed…321 has higher hot strength. 3CR12 A lower cost is required, and the reduced corrosion resistance and resulting discoloration are acceptable. 430 A lower cost is required, and the reduced corrosion resistance and fabrication characteristics are acceptable.

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Corrosion Resistance

Grade 304 stainless steel is excellent in a wide range of atmospheric environments and many corrosive media. It is subject to pitting and crevice corrosion in warm chloride environments, and to stress corrosion cracking above 60 °C (approximate). Grade 304 is considered to be resistant to potable water up to approximately 200 mg/L chlorides at ambient temperatures, reducing to approximately150 mg/L at 60 °C.

Heat Resistance

Grade 304 has good oxidation resistance in intermittent service to 870 °C, and in continuous service to 925 °C. Continuous use of 304 in the 425-860 °C range is not recommended if subsequent aqueous corrosion resistance is important. Grade 304L is more resistant to carbide precipitation and can be heated into this temperature range.

Grade 304H has higher strength at elevated temperatures so is often used for structural and pressure-containing applications at temperatures above 500 °C up to about 800 °C (approximate). 304H will become sensitized in the temperature range of 425-860 °C. Whilst this is not a problem for high-temperature applications, it will result in reduced aqueous corrosion resistance.

Heat Treatment

During Solution Treatment (Annealing) Grade 304 can be heated to - °C and is then cooled rapidly. These grades cannot be hardened by thermal treatment.

Welding

Grade 304 has excellent weldability by all standard fusion methods, both with and without filler metals. AS .6 pre-qualifies welding of 304 with Grade 308 and 304L with 308L rods or electrodes (and with their high silicon equivalents). Heavy welded sections in Grade 304 may require post-weld annealing for maximum corrosion resistance. This is not required for Grade 304L. Grade 321 may also be used as an alternative to 304 if heavy section welding is required and post-weld heat treatment is not possible.

Machining

A "Ugima" improved machinability version of grade 304 is available in bar products. "Ugima" machines significantly better than standard 304 or 304L, giving higher machining rates and lower tool wear in many operations.

Dual Certification

It is common for 304 and 304L to be stocked in "Dual Certified" form, particularly in plate and pipe. These items have chemical and mechanical properties complying with both 304 and 304L specifications. Such dual certified product does not meet 304H specifications and may be unacceptable for high-temperature applications.

The company is the world’s best 304 stainless steel coil for kitchen appliances supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

Typical Applications

• Food processing equipment, particularly in beer brewing, milk processing & winemaking
• Kitchen benches, sinks, troughs, equipment and appliances
• Architectural paneling, railings & trim
• Chemical containers, including for transport
• Heat Exchangers
• Woven or welded screens for mining, quarrying & water filtration
• Threaded fasteners
• Springs