316L stainless steel pipe is a pipe material widely used in construction engineering. The shape of the tube is an oblong hollow steel tube. Mechanical equipment, petrochemical equipment, medical equipment, food and light industry transmission pipelines or mechanical parts will use 316L stainless steel pipes, but many friends will confuse 316L with 316. The following is a brief introduction to the difference between
316L stainless steel pipe and 316 stainless steel pipe:
1. Differences in production costs
The main difference between 316 and 316L is the carbon content. 316L is less than 0.03% and 316 is less than 0.08%. In the austenitic stainless steel series, carbon is an element that easily causes intergranular corrosion. The lower the carbon content, the less the tendency for intergranular corrosion. Therefore, the corrosion resistance of 316L is stronger than 316, and the price is more expensive than 316L.
2. Differences in the strength of stainless steel tubes
The tensile strength of 316 stainless steel pipe is higher than that of 316L stainless steel pipe. The tensile strength of 316 stainless steel pipe is higher than 520MPa ~ (316L) stainless steel pipe. The tensile strength of 316 stainless steel pipe is only greater than 480Mpa. This is because carbon is a strong austenite forming element, which can significantly increase the strength of stainless steel pipes.
3. Differences in practical applications
The cost difference between 316L stainless steel and 316 stainless steel is not big. The corrosion resistance and weldability of 316L stainless steel are obviously better than ordinary 316 stainless steel. From the manufacturer's perspective, stainless steel factories are reluctant to produce because the demand for ordinary 316 stainless steel is very low. Therefore, the actual circulation in the market is basically low-carbon 316 L stainless steel. Generally, 316 stainless steel is rarely sold unless there is a specific demand.
4. Differences in welding
Carbon has a negative effect on the corrosion resistance of stainless steel pipes. Especially for stainless steels that need to be welded, the corrosion resistance of low-carbon 316L stainless steel after welding is lower than that of 316 stainless steel. 316L has good corrosion resistance, and the welding section of 316 stainless steel needs to be solution annealed after welding. If 316L stainless steel is used, solution annealing after welding is not required.
5. Differences in corrosion resistance
316L stainless steel pipe has stronger corrosion resistance and is suitable for strong corrosion areas such as seaside. In addition, 316 stainless steel pipe is not recommended to consider the previous conditions.
6. Differences in the scope of use
In most cases, 304 stainless steel pipe is sufficient to meet the application requirements. Due to the high price of 316L stainless steel pipe, from the perspective of material cost, the use of 316L stainless steel pipe is about 1.5 times that of 304 stainless steel pipe, so the amount of 316L steel pipe should be customized.
How to choose stainless steel material?
1. Before purchasing stainless steel plate, it should be decided according to the use environment and purpose. If it is medical or kitchen, it is recommended to choose sanitary stainless steel. For decoration under pressure, it is recommended to choose 200 series thick-walled pipes. If it is used in an acid-alkaline environment, it is recommended to choose 316 stainless steel.
2. Secondly, when purchasing stainless steel materials, it also depends on whether the materials meet the standards. If you choose 304 material, it depends on whether there is a steel stamp on the pipe. Generally, the authentic 304 stainless steel material will not change color when it encounters acid for 30s. However, if purchasing in large quantities, some samples can be taken and sent to professional institutions for testing.
3. Then, when purchasing stainless steel pipe materials, it depends on whether the surface of the material is smooth, whether the thickness is uniform, whether the color is bright, etc. In particular, seamless steel pipes must be polished during cold drawing or hot rolling, otherwise it is prone to uneven thickness or cracks on the pipe surface. But if there is no requirement for the appearance, it will not affect the use.
4. Finally, when purchasing stainless steel materials, it is best to compare various aspects, or consult some friends who have purchased. Try to choose products with good reputation.
