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
Stainless steel grade 317L is a low carbon version of grade 317 stainless steel. It has the same high strength and corrosion resistance as 317 steel but can produce stronger welds due to the low carbon content.
Corrosion Resistance
317L has excellent corrosion resistance in a wide range of chemicals, especially in acidic chloride environments such as those encountered in pulp and paper mills. Increased levels of chromium, nickel and molybdenum compared to 316L stainless steel improve resistance to chloride pitting and general corrosion. Resistance increases with molybdenum alloy content. 317L is resistant to sulfuric acid concentrations up to 5 percent at temperatures as high as 120°F (49°C). At temperatures under 100°F (38°C) this alloy has excellent resistance to solutions of higher concentration. However, service tests are recommended to account for the affects of specific operating conditions that may affect corrosion behavior. In processes where condensation of sulfur-bearing gases occurs, 317L is much more resistant to attack at the point of condensation than conventional alloy 316. The acid concentration has a marked influence on the rate of attack in such environments and should be carefully determined by service tests.
Chemical Composition
The chemical composition of grade 317L stainless steel is outlined in the following table.
Ni | Cr | Mo | Mn | Si | C | N | S | P | Fe |
11.0 - 15.0 | 18.0 - 20.0 | 3.0 - 4.0 | 2.0 Max | .75 Max | 0.03 Max | 0.1 Max | 0.03 Max | 0.045 Max | Balance |
Mechanical Properties
The mechanical properties of grade 317L stainless steel are displayed in the following table.Properties | Metric | Imperial |
Tensile strength | 595 MPa | 86300 psi |
Yield strength | 260 MPa | 37700 psi |
Modulus of elasticity | 200 GPa | 29000 ksi |
Poisson's ratio | 0.27-0.30 | 0.27-0.30 |
Elongation at break (in 50 mm) | 55% | 55% |
Hardness, Rockwell B | 85 | 85 |
Manufacturing Process
Machining stainless steel grade 317L requires low speeds and constant feeds to reduce its tendency to work harden. This steel is tougher than grade 304 stainless steel with a long stringy chip; however, using chip breakers is recommended. Welding can be performed using most of the conventional fusion and resistance methods. Oxyacetylene welding should be avoided. AWS E/ER 317L filler metal is recommended.
Conventional hot working processes can be performed. The material should be heated to 1149-1260°C (2100-2300°F); however, it should not be heated below 927°C (1700°F). To optimize corrosion resistance, a post-work annealing is recommended.
Shearing, stamping, heading and drawing are possible with grade 317L stainless steel, and post-work annealing is recommended to eliminate internal stresses. Annealing is performed at 1010-1121°C (1850-2050°F), which should be followed by rapid cooling.
Grade 317L stainless steel does not respond to heat treatment.
Applications
Grade 317L stainless steel is widely used in the following applications:- Condensers in fossil
- Pulp and paper manufacturing
- Nuclear fueled power generation stations
- Chemical and petrochemical process equipment.
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.