Kinnari Steel

Kinnari Steel Corporation are exporters, stockiest & suppliers of Stainless Steel 321 Fasteners. They have special quality finishing and duress for long life, high pressure and zero defects.

Contact Us For Your Requirement of Stainless Steel 321 Fasteners

Stainless Steel 321 Fasteners

The product differentiation is based on the premier finish with the minimum burr at the edge . The v shape formation for perfect welding and fabrication of the fittings in mega projects in oil and gas industry for the long life of the product.

Orders at Kinnari Steel are guaranteed fast delivery in the country. The main reason being we have an excellent warehousing and storage facilities for both finished and semi-finished goods.They are made ready as per the urgent requirements of the customers. They are manufactured to sustain very high pressure and product warranty.

Lot of emphasis is placed on the packing and packaging . The Stainless Steel 321 Fasteners are packed in wooden corrugated boxes foiled in plastic wraps and bubble wraps.

BACKGROUND

Grades 321 and 347 are the basic austenitic 18/8 steel (Grade 304) stabilised by Titanium (321) or Niobium (347) additions. These grades are used because they are not sensitive to intergranular corrosion after heating within the carbide precipitation range of 425-850°C. Grade 321 is the grade of choice for applications in the temperature range of up to about 900°C, combining high strength, resistance to scaling and phase stability with resistance to subsequent aqueous corrosion.

Grade 321H is a modification of 321 with a higher carbon content, to provide improved high temperature strength.A limitation with 321 is that titanium does not transfer well across a high temperature arc, so is not recommended as a welding consumable. In this case grade 347 is preferred – the niobium performs the same carbide stabilisation task but can be transferred across a welding arc. Grade 347 is therefore the standard consumable for welding 321. Grade 347 is only occasionally used as parent plate material.

Like other austenitic grades, 321 and 347 have excellent forming and welding characteristics, are readily brake or roll formed and have outstanding welding characteristics. Post-weld annealing is not required. They also have excellent toughness, even down to cryogenic temperatures. Grade 321 does not polish well, so is not recommended for decorative applications.

Grade 304L is more readily available in most product forms, and so is generally used in preference to 321 if the requirement is simply for resistance to intergranular corrosion after welding. However 304L has lower hot strength than 321 and so is not the best choice if the requirement is resistance to an operating environment over about 500°C.

Specification

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.

Physical Properties

Typical physical properties for annealed grade 321 stainless steels are given in the table

Physical properties of 321 grade stainless steel in the annealed condition

Mechanical Properties

Typical mechanical properties for grade 321 stainless steels are given in the table .
Mechanical properties of 321 grade stainless steel

Corrosion Resistance

Equivalent to Grade 304 in the annealed condition, and superior if a weldment in these grades has not been post-weld annealed or if the application involves service in the 425-900°C range. Subject to pitting and crevice corrosion in warm chloride environments, and to stress corrosion cracking above about 60°C.Considered resistant to potable water with up to about 200mg/L chlorides at ambient temperatures, reducing to about 150mg/L at 60°C.

Heat Resistance

Good oxidation resistance in intermittent service to 900°C and in continuous service to 925°C. These grades perform well in the 425-900°C range, and particularly where subsequent aqueous corrosive conditions are present. 321H has higher hot strength, and is particularly suitable for high temperature structural applications.

Heat Treatment

Solution Treatment (Annealing) – heat to 950-1120°C and cool rapidly for maximum corrosion resistance.Stabilising – heat to 870-900°C for 1 hour per 25mm of thickness and air cool. Stabilisation is recommended for most severe service conditions (above 425°C) and particularly for material annealed at the upper side of the annealing temperature range.

Stress Relief – Heat to 700°C for 1 to 2 hours and air cool.

These grades cannot be hardened by thermal treatment.

Welding

Excellent weldability by all standard fusion methods, both with and without filler metals. AS 1554.6 pre-qualifies welding of 321 and 347 with Grade 347 rods or electrodes; high silicon version of 347 is also pre-qualified for welding of 321.

APPLICATIONS

• Aircraft exhaust manifolds
• Expansion Joints
• Bellows
• Furnace Parts
• Heating element tubing
• Heat Exchangers
• Woven or welded screens for high temperature mineral processing
• Spiral welded tube for burner pipes and flues.

Problems that customers face when they buy from other companies:

• Poor after sales service
• Supply of wrong grades
• Material inconsistent with ASTM Standards
• Very hard material for use
• Dubious Practices
• Lack of knowledge
• Product fails under high pressure
• High pricing of the goods due to supplier commission
• No inspection of the goods

Benefits that our company offers:

All Stainless Steel 321 Fasteners are offered with an NACE 3.1 Certification, Mill Test Certification and ISO 17025 Standards by a Government of India approved Laboratory. Positive Material Identification is done on all raw material procured at Kinnari Steel Corporation.

We have exported to over 45 countries including UAE, UK, Iran, Iraq, Qatar, Bahrain, Oman, Yemen, Lebanon, Jordan, Saudi Arabia, Malaysia, Indonesia, Singapore, Australia, New Zealand, USA, Canada, Mexico, Brazi, Netherlands, Germany, Italy, Spain, Serbia, Kuwait, Peru, Nigeria, Poland, South Africa, Denmark, Turkey, Egypt, Venezuela, Kuwait, Madagascar, Angloa & Srilanka.

The Stainless Steel 321 Fasteners are used in Hardware , Petro-Chemical Industry, Oil and Gas Industry , Nuclear Industry, Pulp & Paper Indusry, Research & Development , Mega Projects &Defense& Development Industries. In fact wing to the special grade of steel, Stainless Steel 321 Fasteners are used for all critical applications.

• World class buying experience
• Very quick delivery/ fastest delivery
• Mill test report/ Digital Mill
• 3rd Party inspection
• High pressure sustainability
• Impeccable surface finish
• Product replacement warranty
• After sales support and service
• High quality packaging/ Premium Packaging and Packing for sea and Air transport
• Government and Private Laboratory Testing
• Test certificate from ISO 17025 Standards Laboratory
• Same day shipping of the goods.

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