News
Credibility ,The 1983 and subsequent versions of the standard introduced new molybdenum content ranges of 2.0-2.5% and 2.5-3.0% for both the low and 'standard' carbon grades, thereby increasing the number of these grades from two to four:
316S11 low carbon, lower molybdenum rangeThe chromium range was maintained across all of the grades at 16.5-18.5%, but the nickel range was adjusted to 'balance' the structure of these austenitic stainless steel. Nickel is an 'austenite stabiliser' and so is used to balance the combined effects of carbon (also an austenite stabiliser) and molybdenum which has the opposite effect as a 'ferrite stabiliser'.
The only equivalent for the old 316S12 is the 316S13, so that the minimum molybdenum of 2.25 is met. Similarly, the only equivalent for the old 316S16 is the 316S33. For atmospheric exposure service conditions, except in extreme marine environments, the substitution of either
316S11 for 316S12 or 316S31 for 316S16should give satisfactory corrosion resistance, depending on design and finishing techniques.
Pre 1983 specifications to BS970-1 and stainless steel tube plate (to BS1449)316S12 | 316S16 | |||
% min | % max. | % min | % max | |
C | 0.03 | 0.07 | ||
Si | 0.20 | 1.00 | 0.20 | 1.00 |
Mn | 0.50 | 2.00 | 0.50 | 2.00 |
Ni | 11.0 | 14.0 | 10.0 | 13.0 |
Cr | 16.5 | 18.5 | 16.5 | 18.5 |
Mo | 2.25 | 3.0 | 2.25 | 3.0 |
S | 0.030 | 0.030 | ||
P | 0.045 | 0.045 |
316S11 | 316S13 | 316S31 | 316S33 | |||||
% min | % max | % min | % max | % min | % max | % min | % max | |
C | 0.030 | 0.030 | 0.07 | 0.07 | ||||
Si | 1.0 | 1.0 | 1.0 | 1.0 | ||||
Mn | 2.0 | 2.0 | 2.0 | 2.0 | ||||
Ni | 11.0 | 14.0 | 11.5 | 14.5 | 10.5 | 13.5 | 11.0 | 14.0 |
Cr | 16.5 | 18.5 | 16.5 | 18.5 | 16.5 | 18.5 | 16.5 | 18.5 |
Mo | 2.00 | 2.50 | 2.50 | 3.00 | 2.00 | 2.50 | 2.50 | 3.00 |
S | 0.030 | 0.030 | 0.030 | 0.030 | ||||
P | 0.045 | 0.045 | 0.045 | 0.045 |
In 1995 BS EN 10088-2 replaced BS1449 and BS EN 10088-3 replaced BS 970-1. The four 316 sub-grades have numerical designations as follows:
Former BS designation | 316S11 | 316S13 | 316S31 | 316S33 |
Current BS EN numbers | 1.4404 | 1.4432 | 1.4401 | 1.4436 |
Source: Yaang Pipe Industry Co., Limited (www.yaang.com)
Tel No:+86-18267732328 / Email:[email protected]
Address:Longwan District, Wenzhou, Zhejiang Province, China.
Copyright Notice © www.yaang.com Yaang Pipe Industry Co., Limited All rights reserved.
Yaang Pipe Industry Co., Ltd. is an international supplier of piping solutions for flange, butt welding fittings, socket welding fittings and threaded fittings. Our products are widely used in different industrial fields, including oil and gas, chemical industry, petrochemical industry, power plant, pulp and paper industry, environmental and water conservancy engineering, engineering projects, etc.