Stainless steel square tube is a name for stainless steel square tubes, that is, steel tubes with equal side lengths. It is made of strip steel after process treatment. Generally, the strip steel is unpacked, flattened, crimped, welded to form a round tube, and then rolled into a square tube from the round tube and then cut to the required length.
square tubes are formed by extruding seamless round tubes.
1. Performance index analysis of square pipe - plasticity
Plasticity refers to the ability of metal materials to produce plastic deformation (permanent deformation) without damage under load.
2. Performance Index Analysis of Square Tube - Hardness
Hardness is a pointer to measure the softness and hardness of metal materials. The most commonly used method of measuring hardness in production is the indentation hardness method, which uses a certain geometric shape of the indenter to press into the surface of the metal material to be tested under a certain load, and the hardness value is determined according to the degree of indentation.
Metals can react with oxygen in the atmosphere to form an oxide film on the surface, and the iron oxide formed on ordinary carbon steel will continue to oxidize, causing the rust to continue to expand and eventually form holes. This can use paint or oxidation-resistant metal plating to protect the surface of carbon steel, but this protective layer is only a thin film. If the protective layer is damaged, the steel below will start to rust again. Whether the stainless steel pipe is corroded is related to the chromium content in the steel. When the chromium content in the steel reaches 12%, in the atmosphere, a layer of passivated and dense chromium-rich oxide is formed on the surface of the stainless steel pipe to protect the surface and prevent corrosion. further reoxidation. This kind of oxide layer is extremely thin, and the natural luster of the steel surface can be seen through it, making the stainless steel have a unique surface. If the chromium film is damaged, the chromium in the steel and the oxygen in the atmosphere will regenerate a passivation film to continue to play a protective role. In some special environments, stainless steel will also fail due to some local corrosion, but unlike carbon steel, stainless steel will not fail due to uniform corrosion, so the corrosion allowance is meaningless for stainless steel pipes
Standard | Product Level | Steel Grade | Yield Strength (min), Mpa | Tensile Strength(MPa) |
API 5L GB/T9711.2 | PSL 1 | A or L210 | 210 | 335 |
B or L245 | 245 | 415 | ||
x42 or L290 | 290 | 415 | ||
X46 or L320 | 320 | 435 | ||
X52 or L360 | 360 | 460 | ||
X56 or L390 | 390 | 490 | ||
X60 or L415 | 415 | 520 | ||
X70 | 483 | 565 | ||
PSL 2 | BR or L245R | 245~450 | 415~760 | |
X42R or L290R | 290~495 | 415~760 | ||
BN or L245N | 245~450 | 415~760 | ||
X42N or L290N | 290~495 | 415~760 | ||
X46N or L320N | 320~525 | 435~760 | ||
X52N or L360N | 360~530 | 460~760 | ||
X56N or L390N | 390~545 | 490~760 | ||
X60N or L415N | 415~565 | 520~760 | ||
X65N or L450N | 425~566 | 525~760 | ||
X70 or L480 | 484~565 | 565~768 | ||
X80 | 552~690 | 621~827 |