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What is the difference between a slotted stainless steel tube and a seamless stainless steel tube (2)?
- Sep 16, 2018 -

5, corrosion resistance

     Corrosion resistance also depends on the composition of the alloy. The corrosion resistance of the seamless stainless steel tube with the same chemical composition and the completely heat treated slotted stainless steel tube is consistent. Supplemental testing provided by ASTM demonstrates that the corrosion resistance of the weld is equivalent or better than the metal being welded. In the case of acid chloride, the corrosion of the welded joint of the incompletely heat treated seamed steel pipe will accelerate, but this is only the need of corrosion test, and the actual environment is not so bad.

6, bending and extensibility

   The extensibility of the weld can be verified by the following test specified by ASTM: bending 45°, then bending to 90°, and then flattening along the weld; then turning the stainless steel with the seam pipe to repeat the above steps to make the weld bend inner diameter reach 180° . The standard for the pass quality of welds is that tearing or intergranular separation is not allowed at 40x magnification. The bending radius of the pipe is controlled by the composition of the alloy, and the minimum bending radius is generally 2d. The ideal welding condition is that the weld is in a neutral or pressurized state. Moreover, the pipe should be annealed to reduce its hardness, thereby improving the bending performance.

7, the price

     The price of a slotted stainless steel tube is usually only half that of a stainless steel seamless tube.

8, wall thickness / diameter

     Thin-walled stainless steel pipes of small thickness/diameter value are preferably produced by welding; thick-walled pipes of large thickness/diameter value are preferably formed by stamping.

9, comprehensive quality

     In general, the quality of a slotted stainless steel tube is superior to that of a seamless stainless steel tube because the slotted stainless steel tube is made of a precision cold rolled sheet that has been inspected and passed, so that any defects are limited to the weld. The seamless tube is stamped from a stainless steel billet, resulting in many tearing in the extruded tube wall. The eddy current test shows that the defective rate of the slotted stainless steel tube is usually lower than the defective rate of the seamless stainless steel tube. With ultrasonic testing, the background noise of seamless stainless steel tubes is so large that it is difficult to find defects. The background noise of the slotted stainless steel tube is very low, and it is easy to find the defect.