Chemical Composition: 321 stainless steel contains the element of titanium (Ti), while 304 stainless steel does not contain titanium. The addition of titanium makes 321 stainless steel have better resistance to high temperatures.

Heat Resistance: Due to the inclusion of titanium, 321 stainless steel welded tubes have better heat resistance in high temperature environments and can withstand higher temperatures, while 304 stainless steel welded tubes have relatively low heat resistance.

Corrosion Resistance: 321 stainless steel welded tube is stronger than 304 stainless steel welded tube in terms of corrosion resistance. 321 stainless steel welded tube has good corrosion resistance to organic acids and oxidizing media at high temperatures, while 304 stainless steel welded tube has poor corrosion resistance.

Physical Properties: Due to the addition of titanium elements, the hardness and strength of 321 stainless steel welded tube is slightly higher than 304 stainless steel welded tube.

Chemical Composition: 321 stainless steel contains the element of titanium (Ti), while 316 stainless steel contains the element of molybdenum (Mo). The addition of these elements makes the two stainless steels have different characteristics and ranges of application.

Heat Resistance: Due to the inclusion of titanium elements, 321 stainless steel welded tubes have better heat resistance in high temperature environments and can withstand higher temperatures. And 316 stainless steel welded pipe in high temperature performance is relatively weak.

Corrosion Resistance: 316 stainless steel welded tube is better than 321 stainless steel welded tube in terms of corrosion resistance. 316 stainless steel welded tube has better corrosion resistance in chloride environment and is suitable for seawater and corrosive media applications.

Physical Properties: The corrosion resistance and strength of 316 stainless steel welded pipe is relatively high due to the addition of molybdenum, while the corrosion resistance and strength of 321 stainless steel welded pipe is slightly inferior to 316 stainless steel.

The service life of 321 stainless steel welded tube depends on a variety of factors, including the use environment, operating conditions and proper maintenance. In general, 321 stainless steel welded tube has a long service life.

Due to the excellent high temperature resistance and corrosion resistance of 321 stainless steel welded pipe, its performance in high temperature and corrosive environments is relatively stable. When properly selected, installed and used, the life of 321 stainless steel welded pipe can reach decades or even longer.

However, it should be noted that the service life is also affected by other factors, such as the design quality of the pipe, the operating temperature and pressure, the nature of the chemical medium, and the mechanical stress of the pipe. In addition, regular maintenance and inspection are also important factors to ensure the life of stainless steel welded pipes.

Therefore, to ensure the best service life of 321 stainless steel welded pipes, it is recommended to follow the guidelines and industry standards of stainless steel tube suppliers and to perform proper maintenance and overhaul.

Cleaning: Clean the surface of the stainless steel welded pipe regularly to remove dirt and buildup. Mild cleaners, soapy water, or non-abrasive cleaners can be used, avoiding chlorinated or acidic cleaners.

Avoid Scratching: Avoid using hard and abrasive materials to scratch the surface of the stainless steel welded pipe to prevent scratches and damage.

Corrosion Prevention: Avoid prolonged exposure to environments containing salt, acidic or alkaline substances, which may have a corrosive effect on the stainless steel welded pipe. If exposed to these substances, they should be cleaned immediately and dried thoroughly.

Regular Inspection: Check the welded tube regularly for cracks, corrosion, or other damage. If problems are found, take prompt measures to repair or replace them.

Use Appropriate Sealing Materials: When connecting or installing stainless steel welded tubes, use appropriate sealing materials to ensure that the connection points are sealed and corrosion-resistant.

Avoid Excessive Temperatures: Avoid exposing stainless steel welded tubes to excessive temperatures to prevent the deformation or annealing of the material.

Avoid Excessive Pressure: Avoid exposing stainless steel welded pipe to pressures that exceed its capacity to prevent rupture or deformation of the pipe.