Stainless Steels and Specialty Alloys for Modern Pulp and Paper Mills Reference Book Series No 11 025 The material presented in this publication has been prepared for the general information of the reader and should not be used or relied on for specific applications without first securing competent advice. The Nickel Development Institute, its members, staff and consultants do not represent or warrant its suitability for any general or specific use and assume no liability or responsibility of any kind in connection with the information herein. Prepared by a Task Force of the Metals Subcommittee of the Corrosion and Materials Engineering Committee of the Technical Association of the Pulp and Paper Industry and the Nickel Development Institute Senior Editor: Arthur H.Tuthill P.E. [...]... duplex stainless steels were found very useful in pumps and rolls in pulp and paper mills even before the AOD process of stainless steel made possible the addition of nitrogen.Today the duplex stainless steels are the principal and preferred alloys for suction rolls Cast duplex stainless steels, due to their better resistance to sand and grit abrasion and better corrosion resistance, have replaced and. .. lower carbon martensitic stainless steels, CB6 (J91804) and CA-6NM (J91540) like the low carbon ferritic, S41003, were developed for increased weldability.They have found applications where higher strength and abrasion resistance are needed Stainless Steels and Specialty Alloys for Pulp and Paper 18 3 CHARACTERISTICS 3.5 OF COMMON ALLOYS steel, clad and weld overlaid digesters for new construction Over... higher minimum N, Cr, and Mo S32205 is often preferred for procurement Fe + Cr *W is about half as effective as Mo in increasing corrosion resistance in acid-chloride environments Stainless Steels and Specialty Alloys for Pulp and Paper 10 Table 2-2 Common Mechanical Properties and Pitting Resistance Equivalent Number (PREN) of Wrought Corrosion Resistant Alloys for the Pulp and Paper Industry UNS EN... Increase Strength and Corrosion Resistance 304 (18-8) Add 2-3% Mo Add 3-4% Mo Add 4-5% Mo Add 6% Mo Add 7% Mo Add More Mo + Ni ➜ ➜ ➜ ➜ ➜ ➜ 316L 317L 904L 317LMN 6% Mo Family 7% Mo Family Ni Cr Mo Alloys Add Mo to Increase Corrosion Resistance 17 Stainless Steels and Specialty Alloys for Pulp and Paper 3 CHARACTERISTICS NOTES OF COMMON ALLOYS 3.3 FERRITIC STAINLESS STEELS Ferritic stainless steels are distinguished... conservation equal harsh process conditions,” Arhippainen, Gullichsen & Co., Helsinki, August 21, 2001 9 Stainless Steels and Specialty Alloys for Pulp and Paper 2 TABLES OF COMPOSITION AND PROPERTIES OF COMMON ALLOYS Table 2-1 Typical Composition of Wrought Corrosion Resistant Alloys for the Pulp and Paper Industry, in Weight Percent Typical Composition - % Common UNS EN(1) Cmax Cr S30300 S30400 S30403... pulp and paper industry,” in ASM Metals Handbook, 1987, pp 1186–1220 5 Jonsson, K.-J., Stainless steels in the pulp and paper industry,” Chap 43 in Handbook of Stainless Steels, McGraw Hill, 1977 6 Johnson, A P., et al., “Successfully producing elemental chlorine-free pulp in the Americas now and in the future,” TAPPI J., 79(7): 61–70 (1996) 7 Kouris, M “Mill Control and Control Systems: Quality and. .. because users have drawings and qualified procedures for these grades as nickel-base alloys Examples of grades that are now in the A-specifications are 904L (N08904), Alloy 20 (N08020), and two of the 6% Mo grades (N08367 and N08926) Stainless Steels and Specialty Alloys for Pulp and Paper 12 2 ALLOY COMPOSITION & PROPERTIES Table 2-4 Typical Composition, Mechanical Properties and Pitting Resistance Equivalent... precipitates as chromium carbide leaves a zone adjacent to the weld 15 Stainless Steels and Specialty Alloys for Pulp and Paper 3 CHARACTERISTICS NOTES OF COMMON ALLOYS Swedish designation for the 0.05% max C grade is 2347, and the EN/DIN is 1.4401.There are no UNS designations for the 0.05% max C grades In mixed stainless steel and carbon steel assemblies where the carbon steel must be stress relieved,... austenitic alloys. The strengthening effect of N has allowed warehouses to offer “dual certified grades.” Dual certified grades have the slightly higher strength of the 0.08% C grades and the low carbon of the “L” grades, which makes the dual certified grades suitable for welded fabrication The 6% Mo stainless steels, which have become so important for the Stainless Steels and Specialty Alloys for Pulp and Paper. .. to caustic SCC (in the impregnation zone) with stainless weld overlay bands has not been successful.The residual 31 Stainless Steels and Specialty Alloys for Pulp and Paper 4 DIGESTERS NOTES 4.3 ANCILLARY EQUIPMENT Stainless steels have been used as materials of construction for much of the equipment ancillary to digesters.This includes piping, valves, and pumps Some of the major ancillary equipment . August 21, 2001 Stainless Steels and Specialty Alloys for Pulp and Paper 9 2. TABLES OF COMPOSITION AND PROPERTIES OF COMMON ALLOYS Stainless Steels and Specialty Alloys for Pulp and Paper 10 Table. COMPOSITION & PROPERTIES Stainless Steels and Specialty Alloys for Pulp and Paper 12 Table 2-3 6% and 7% Mo Austenitic Stainless Steels for Use in the Pulp and Paper Industry Not applicable B675,. 6% and 7% Mo Austenitic Stainless Steels ASTM Specifications for 6% and 7% Mo Stainless Steel Pipe 2.ALLOY COMPOSITION & PROPERTIES Stainless Steels and Specialty Alloys for Pulp and Paper 13 Table