JIS G3463-1994 Stainless Steel Tubes for Boiler and Heat Exchanger
JIS G3463-1994 is a Japanese Industrial Standard that defines the mechanical properties of stainless steel tubes used for boilers and heat exchangers. The standard covers the requirements for three grade series, including grade SUS304T, SUS316T and SUS444T. This standard applies to stainless steel tubes with an outer diameter of 12.7 mm or more for high pressure boilers, and to stainless steel tubes with an outer diameter of 8.0 mm or more for low pressure boilers and heat exchangers.
The mechanical properties of the three grades defined by JIS G3463-1994 follow the values defined in the Japanese Industrial Standard JIS G3448-1994. The mechanical properties of JIS G3448-1994 are defined as follows: tensile strength (N/mm2), yield stress/proof stress (N/mm2), elongation (% in 50mm length) and hardness (HB).
The mechanical properties given in the JIS G3463-1994 standard not only apply to seamless tubes but also to welded and welded-and-drawn (cold finished) tubes. The material covered by this standard is austenitic stainless steel, which does not cover ferritic stainless steel, martensitic stainless steel, precipitation hardening stainless steel, or other non-austenitic stainless steels.
For grades SUS304T, SUS316T and SUS444T, the mechanically tested parts shall be prepared from full length tubes. The test samples shall be taken from the center of the test part in the direction of the axis of the tube and shall not be more than 50 mm in length. The tests shall be conducted at room temperature, and at temperatures up to 600°C, where applicable, for corrosion-resistant stainless steels.
JIS G3463-1994 includes requirements for tolerance, allowable deviations and straightness of stainless steel tubes. The allowable outer diameter and wall thickness deviations shall not exceed ± 5% of the specified dimensions. The tolerance of the length of the components shall not exceed ± 2.5 mm, and the allowance of the out-of-straightness shall not exceed ± 0.3% of the length.
In conclusion, JIS G3463-1994 is a Japanese industrial standard that defines the mechanical properties of austenitic stainless steel tubes for boilers, heat exchangers and pressure vessels. This standard specifies the requirements for three grade series, SUS304T, SUS316T and SUS444T. The mechanical properties defined in the standard apply to seamless, welded and welded-and-drawn (cold finished) tubes. It also defines the allowable deviations in the outer diameter and wall thickness, as well as the tolerance and straightness of the stainless steel tubes.