Which is more suitable for stainless steel heat exchange tubes: 304 or 304L stainless steel?

Stainless steel heat exchange tubes are an integral part of heat exchangers, used for heat exchange between two media, and are widely used in our daily lives.

However, many people still lack understanding of stainless steel heat exchange tubes, including their specifications and materials. Let's learn more about heat exchanger tubes.

 

 

1. Specifications of Stainless Steel Heat Exchange Tubes

 

Common heat exchange tubes are available in sizes ranging from 10mm to 114mm, with thicknesses from 0.6mm to 3.0mm. Lengths can be customized according to specific needs. Small diameter tubes have high fluid resistance, making them difficult to clean and prone to clogging. However, large-diameter stainless steel tubes offer a different approach. Their resistance is not as high as that of small-diameter tubes, making them easier to clean. Therefore, small diameter tubes are used for cleaner fluids, while large diameter tubes are used for viscous or dirty fluids.

 

2. Materials of Stainless Steel Heat Exchange Tubes

 

Both 304 and 304L stainless steel, two widely used austenitic stainless steels, are used in stainless steel heat exchange tubes. As for which 304 or 304L stainless steel is more suitable, it depends on their performance and production process.

Let's first look at basic performance. The core function of a heat exchange tube is to conduct heat generated by the gas. The better the thermal conductivity, the better the heat transfer. 304 and 304L stainless steel have the same thermal conductivity.

From a production perspective, stainless steel heat exchange tubes are very difficult to process, requiring very high requirements for internal structure and welding techniques. Any carelessness during the manufacturing process can affect the quality of the entire unit and pose risks to the manufacturing process. 304 and 304L stainless steel can be used for hot processing such as stamping and bending, and do not undergo heat hardening. As can be

 

3. The performance of these two stainless steels is similar in general use.

 

However, compared to 304 stainless steel, 304L stainless steel has better weldability. After welding or stress relief, it can maintain excellent resistance to intergranular corrosion, and its thermal shock resistance is higher than that of 304 stainless steel, making the entire machine more stable and reliable.