ASTM A335/A335M-95a Standard Specification for Seamless Ferritic Alloy Steel Pipe for High-Temperature Service
This specification covers seamless ferritic alloy-steel pipe for high-temperature service. The pipe shall be suitable for bending, flanging (vanstoning), and similar forming operations, and for fusion welding. Heat treatment may be required to produce the desired mechanical properties without adversely affecting the steels metallurgical characteristics. Grade Nominal Composition C Mn P S Si Cr Mo V Max P1/P1A 0.15 0.30- 0.61 0.025 0.025 0.50 0.80-1.25 0.44-0.65 0.20-0.30 P2/P2A 0.15 0.30- 0.61 0.020 0.010 0.50 1.00-1.50 0.44-0.65 0.20-0.30 Grade Nominal Composition Blank 0.04-0.08 0.25- 0.50 0.025 0.025 0.90 2.00- 2.50 0.75-1.05 0.03 P5/P5A 0.15 max 0.30- 0.60 0.025 0.025 0.50 4.00-6.00 0.45-0.65 0.05-0.15 P11/P11A 0.05- 0.15 0.30- 0.60 0.025 0.025 0.50 0.85-1.25 0.44-0.65 0.20-0.30 P12/P12A 0.05- 0.15 0.30- 0.60 0.025 0.020 0.50 1.90-2.60 0.80-1.25 0.25-0.35
P22/P22A 0.05- 0.15 0.30- 0.61 0.025 0.020 0.50 2.00-2.50 0.87-1.13 0.20-0.30 P91/P91A 0.08- 0.12 0.30- 0.60 0.020 0.010 0.20 8.00-9.50 0.85-1.05 0.15-0.25 Specific alloy and temper is designated by the suffix A.
Pipes shall be furnished in the normalized and tempered or quench and tempered condition. The ferritic grade and the corresponding ASTM Designation shall consist of the following, except when electrical welding from billet or from other manufacturing process is applied:
1. P1 or P1A or P12 or P12A as defined in ASTM A335/A335M. 2. P2 or P2A as defined in ASTM A335/A335M. 3. P5, P11, P22, and P91 as defined in ASTM A335/A335M, provided they exhibit referred properties in these grades of ferritic alloy-steel pipe.
The test
shall be conducted in accordance with the requirements of ASTM A530/A530M. The following tests shall be made to determine the mechanical properties of the pipes:
1. Tensile test
2. Bend Test
3. Charpy Test
4. Reverse Bend Test
5. Impact Test
6. Low Temperature Impact Test
7. Micrographic Examination
8. Ferrite Examination
9. Hardness Test
The annealing treatment after cold working for ferritic grade is mandatory. The minimum amount of cold working shall be capable of producing the desired mechanical properties to insure uniformity.
All AsTM Nos. for chemical and mechanical requirements specified in section 4 of ASTM A 530/A 530M shall apply.
The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other.
The materials shall conform to the above chemical composition and shall show satisfactory results of mechanical tests as required by ASTM A 335/A 335M.
The steel pipe shall have been melted by either electric furnace, open hearth furnace, or basic oxygen process. The steel shall be made by one or more of the following processes:
1. Open-hearth furnace
2. Electric-arc furnace
3. Electric-resistance furnace
4. Vacuum arc melting
The steel pipe shall have been manufactured by seamless or electric fusion welding or electric-resistance welding processes. Tensile testing, bend testing, and hydrostatic testing require only samples from each steel grade-size of pipe to be teated. The number of tests from the various yield strengths is detailed in the specification.
The hydrostatic test pressure for each size, nominal diameter, and wall thickness shall not be less than three times the design pressure revealed by the results of tensile tests of samples of each pipe size and of each steel grade-size combination. The design pressure for a size, nominal diameter, and wall thickness, revealed by the results of the tensile tests, shall be that specified in the design standard of a specification prepared by the user and agreed to by the producer.
The surface of the pipes by visual inspection shows that the pipes have been procured and manufactured under the specified standard. The ends of ferritic alloy-steel pipe shall be bevelled or threaded, and threaded ends shall meet ANSI/ASME B1.20.1, when agreed upon between purchaser and producer.
The pipes shall be marked with the name of the manufacturer, heat number and the ASTM A335/A335M Number.
