Basic Info.
Standard
ANSI, DIN, GOST, En1092-1
Manufacturing Way
Forging
Ndividual Drawing
Welcome
Transport Package
Pallet/Wooden Case
Product Description
Austenitic Stainless Steel
Austenitic steels are the most popular grades of stainless steels because of their ductility, ease of working and good corrosion resistance and are very commonly used in manufacture of piping components. Austenitic steels are non-magnetic and non-hardenable by heat treatment, however they can be hardened by cold working. The most commonly used stainless steel grades are Type 304, Type 316 and Type 321.
Stainless steel grades with suffix L have low carbon content. The low carbon content provides good weldability and good corrosion resistance after welding, however they have lower strength than the grades with higher carbon content. The dual certified grades of stainless steel are commonly used in the industry such as SS 304/304L or SS 316/316L. For e.g. the SS 304/304L dual certified grade has lower carbon content similar to SS 304L grade but higher mechanical strength of SS 304 grade.
Type 304 grade contains approximately 18% Chromium and 8% Nickel.
Effect of carbon on corrosion resistance
The lower carbon variants (316L) were established as alternatives to the standards (316) carbon range grade to overcome the risk of intercrystalline corrosion (weld decay), which was identified as a problem in the early days of the application of these steels. This can result if the steel is held in a temperature range 450 to 850°C for periods of several minutes, depending on the temperature and subsequently exposed to aggressive corrosive environments. Corrosion then takes place next to grain boundaries.
If the carbon level is below 0.030% then this intercrystalline corrosion does not take place following exposure to these temperatures, especially for the sort of times normally experienced in the heat affected zone of welds in thick sections of steel.
Effect of carbon level on weldability
There is a view that the low carbon types are easier to weld than the standard carbon types.
There does not seem to be a clear reason for this and the differences are probably associated with the lower strength of the low carbon type. The low carbon type may be easier to shape and form, which in turn may also affect the levels of residual stress left the steel after is forming and fitting up for welding. This may result in the standard carbon types needing more force to hold them in position once fitted-up for welding, with more of a tendency to spring-back if not properly held in place.
The welding consumables for both types are based on a low carbon composition, to avoid intercrystalline corrosion risk in the solidified weld nugget or from the diffusion of carbon into the parent (surrounding) metal.
Dual-certification of low carbon composition steels
Commercially produced steels, using current steelmaking methods, are often produced as the low carbon type as a matter of course due to the improved control in modern steelmaking. Consequently finished steel products are often offered to the market dual certified to both grade designations as they can then be used for fabrications specifying either grade, within a particular standard.
Raw Material Specification
Introduction
Material to F44 Super Austenitic Stainless Steel is described as a 6% Mo super austenitic stainless
steel. The steel combines moderate mechanical strength (typically over 300 MPa yield strength) and high ductility with excellent corrosion resistance in seawater and a variety of industrial environments. Typically the alloy has a PREn(Pitting Resistance Equivalent) of 42-44 which ensures that the resistance to pitting corrosion is high. In addition, the steel provides good resistance to crevice corrosion.
Ambient and subzero temperature notch ductility is very good. These attributes mean that this high molybdenum stainless steel can be used successfully as an alternative to 300 series austenitic stainless steels (such as type 316) in applications where higher mechanical strength and/or
enhanced resistance to pitting and crevice corrosion is required. This alloy possesses a lower yield strength than that of duplex stainless steel (and much lower than that of super duplex steel) and pitting resistance which is comparable to super duplex stainless steel (such as UNS S32760 / S32750).
Corrosion Resistance
F44 Super Austenitic Stainless Steel offers higher resistance to abrasion, erosion and cavitation erosion than other austenitic stainless grades such as 316. F44 Super Austenitic Stainless Steel has excellent resistance to corrosion in sea water and concentrated halide environments, with good resistance to crevice corrosion in seawater.
The following sections will discuss in detail about stainless steel grade F44.
Chemical Composition(%)
Steel Grade | C | Si | Mn | P | S | Cr | Ni | Mo | Cu | N |
F44 | 0.02 max | 0.8 max | 1.0 max | 0.030 max | 0.010 max | 19.5-20.5 | 17.5-18.5 | 6.0-6.5 | 0.50-1.00 | 0.18-0.22 |
1.4547 | 0.02 max | 0.7 max | 1.0 max | 0.030 max | 0.010 max | 19.5-20.5 | 17.50-18.50 | 6.0-7.0 | 0.50-1.00 | 0.18-0.25 |
Mechanical Properties (Annealed)Hardness (HB) | Tensile Strength (Mpa) | Yield Strength (Mpa) | Elongation (%) (Long.) | Impact Value (J) (Long.) |
260 max | 650-850 | 300-340 | 35 min | 100 min |
Fabrication and Heat Treatment
Machinability
Stainless steel grade F44 is quite tough to machine due to the extremely high work hardening rate and lack of sulfur content; however using sharp tools, overpowered machine tools, positive feeds, good amount of lubrication, and slow speeds tend to provide good machining results.
Welding
Welding of stainless steel grade F44 requires filler material without which it results in poor strength properties. Filler metals such as AWS A5.14 ERNiCrMo-3, and alloy 625 are recommended. Electrodes used in the process, have to match with AWS A5.11 ENiCrMo-12.
Annealing
Annealing of this material should be performed at 1149-1204°C (2100-2200°F), which should be followed by a water quench.
Hot Working
Forging, upsetting and other operations relating to this material can be performed at 982 - 1149°C (1800 - 2100°F). It is recommended that temperatures do not exceed this range as it would result in scaling and reduction in the workability of the material. To re-attain maximum corrosion resistant properties, it is advisable to perform post-process annealing.
Cold Working
Cold working can be carried out using all the traditional methods; however the process would be tough due to its high work hardening rate. The result will provide the material with increased strength and toughness.
Hardening
Stainless steel grade F44 does not respond to heat treatment. Hardening is possible only through cold reduction.
Applications
Stainless steel grade F44 is used in the following areas:- Saltwater handling
- Tall oil distillation columns
- Flue gas desulfurization scrubbers
- Components used in petroleum production
- Food processing equipment
- Process equipment in chemical industry
- Bleaching equipment in the pulp and paper industry
- Flue-gas cleaning
- Desalination
- Heat exchangers
Shipped Flange Photos
Production Range
DN15-DN3000
Maximum weight 6tons
25,000tons production annual year
Manufacturing Standard
ANSI B16.5,ANSI B16.47 Series A&B,ANSI B16.48,ANSI B16.36
API 605,API 16D,API 17D
BS4504,BS3293
DIN
AS
EN1092-1
GOST
EEMUA145
Inspection Certificate
EN10204-3.1
EN10204-3.2 byTUV,BV,Lloyds,GL,DNV,SGS,ABS,RINA,Moody or other third parties
Address:
Building 9, No. 1558, Kangqiao Rd., Pudong, Shanghai, China
Business Type:
Manufacturer/Factory, Trading Company
Business Range:
Chemicals, Construction & Decoration, Industrial Equipment & Components, Manufacturing & Processing Machinery, Metallurgy, Mineral & Energy, Tools & Hardware
Management System Certification:
ISO 9001, ISO 14001, ASME
Company Introduction:
Dingxiang CHN Flange Forging Co., Ltd. is located in the State Dingxiang named"hometown of forging", founded in 2006 invested by TianYuan(HK) International Limited be specialized in manufacturing various kinds of high quality flange and other forging.
Being a designer and manufacturer of flange and forgings in the industry. We provide both standard and customized designs in a large range of different pipeline system. Our main products include Welding Neck, Slip-on, SocketWelding, Threaded, Binld according to ANSI, DIN, JIS, EN, made of ASTM A105, A350, A694, A182, ect. Our engineers are able to design the right products to fit your application and the best solution for your requirements. The products have been wildely used in the industries of petroleum, chemical, foodstuff, metallurgy, construction, electric power and so on.
We have a 4, 000tons Hydraulic Machine and 6300 Ring Rolling Machine operating flange&ring production, the maximum outside diameter is up to 6000mm, maximum gross weight up to 6tons. Our annual production capacity of Flange is 25000tons;
We do a whole set of chemical and mechanical performance test, metallurgical structure, hardness test, NDE test, salt-fog test, film thickness test, roughness test, and the lowest temperature of impact test can be -196 degree C.
We treat Quality, Customer, Market, Upgrade as the most important.