Analysis | Mechanical_Properties | Applications | Machineability_and_Weldability | Heat_Treating | Tolerances | Speedy Metals items |
304/304L stainless steel pipe is a very low carbon "18-8" austenitic chromium-nickel steel with good corrosion resistance and superior resistance to intergranular corrosion following welding or stress relieving. The low carbon content limits the formation of harmful carbides to such an extent that this grade may be safely used for most operations of welded construction, and where the service temperature is limited to 800° F. It is non-magnetic in the annealed condition and not hardenable by heat treatment. Both hardness and tensile strength can be increased by cold working, which may cause slight magnetism. Available in limited sizes of rounds, squares, and rectangles and 304 Stainless Pipe.
304/304L stainless tube conforms to : Welded: ASTM A249, ASTM A269, ASME A249, ASME SA269, Seamless: ASTM A269, ASTM A514, ASTM A511, ASME SA 269 Cold Drawn and Seamless: ASTM A213, ASME SA 213 Square and Rectangle Tube: ASTM 554 Stainless Steel Pipe: ASTM A312 (seamless), A312 (welded), A376 (welded)
The above values are average and may be considered as representative of 304/304L stainless structural tubes
304/304L is used almost exclusively for parts requiring machining, welding, grinding, or polishing where good corrosion resistance is also required. It is a good general all-purpose stainless grade. Good in corrosive environments as in paper and chemical industries and cryogenic services. Used where corrosion resistance and good mechanical properties are primary requirements. 304/304L is widely accepted in such industries as dairy, beverage, and other food industries where the highest degree of sanitation and cleanliness is of prime importance. Parts for handling acetic, nitric, and citric acids, organic and inorganic chemicals, dyestuffs, crude and refined oils, etc., are fabricated from this material. Because of its lack of magnetism it is highly desirable for instruments. It is also widely used for architectural trim. 304/304L is used in applications where corrosion resistance is required, but elevated temperatures are not involved. 304/304L finds particular use in applications requiring welding. 304/304L has good drawing, forming, and stamping properties.
SIZE CONVERSION Schedule 40
Pipe Size | O.D. (in) | Wall (in) | Pipe Size | O.D. (in) | Wall (in) |
1/4 | .540 | .088 | 2-1/2 | 2.875 | .203 |
3/8 | .675 | .091 | 3 | 3.500 | .216 |
1/2 | .840 | .109 | 3-1/2 | 4.000 | .226 |
3/4 | 1.050 | .113 | 4 | 4.500 | .237 |
1 | 1.315 | .133 | 5 | 5.563 | .258 |
1-1/4 | 1.660 | .140 | 6 | 6.625 | .280 |
1-1/2 | 1.900 | .145 | 8 | 8.625 | .322 |
2 | 2.375 | .154 | 10 | 10.750 | .365 |
Machinability is rated at 45% of B1112. Average cutting speed 75 ft/min. Easily welded by all commercial processes except forge or hammer welding. The resultant weld has good toughness and ductility. Annealing is recommended after forging to maintain maximum corrosion resistance. 304/304L can be forged between 2100°-2350° F. Do not forge below 1700° F.
304/304L is not hardenable by heat treatment. Cold working increases tensile strength and hardness. Annealing range is between 1850° and 2050°F. Cool rapidly. Water should be used for heavier sections; air for lighter sections. The stress relieving range is between 400° and 750°F
OD (inches) | Wall Thickness | OD Tolerance (+/-) |
½ to 1 | .025 to .065 | .005 |
½ to 1 | Over .065 to .120 | .010 |
Over 1 to 1-1/2 | .025 to .065 | .008 |
Over 1 to 1-1/2 | Over .065 to .120 | .010 |
Over 1-1/2 to 2 | .025 to .049 | .010 |
Over 1-1/2 to 2 | Over .049 to .083 | .011 |
Over 1-1/2 to 2 | Over .083 to .148 | .012 |
Over 2 to 2-1/2 | .035 to .065 | .012 |
Over 2 to 2-1/2 | Over .065 to .109 | .013 |
Over 2 to 2-1/2 | Over .109 | .014 |
Over 2-1/2 to 3-1/2 | .065 to .165 | .020 |
Over 2-1/2 to 3-1/2 | Over .165 to .220 | .025 |
Over 3-1/2 to 5 | .083 to .165 | .020 |
Over 3-1/2 to 5 | Over .165 to .220 | .025 |
Nominal Pipe Size | Welded A312 |
1/4 to 1-1/2 IPS | +.015/-.031 |
2 to 4 IPS | +.031/-.031 |
5 to 8 IPS | +.093/-.031 |