What factors cause the failure of stainless steel heat exchange tubes?
By: mxgy,
Common faults of stainless steel heat exchange tubes, such as corrosion, scaling, material and manufacturing defects, etc., are mainly caused by multiple factors such as material defects, operating environment, and process operation.
1. Corrosion problems
Medium corrosion:
Acidic/alkaline media (such as acid and alkali solutions in chemical production) directly corrode the tube, causing thinning or perforation of the tube wall.
When the chloride ion concentration is ≥500ppm, austenitic stainless steels such as 316L are prone to pitting or intergranular corrosion, accelerating material failure.
Electrochemical corrosion:
Other metal dust (such as iron filings) or pollutants adhere to the tube wall, forming micro-batteries in a humid environment, causing local corrosion.
2. Scaling and clogging
Scale (calcium and magnesium salt deposition) or dirt (organic/particulate accumulation) adheres to the inner wall, reducing heat transfer efficiency and increasing the risk of local corrosion.
3. Material and manufacturing defects
Uneven tube wall:
Poor quality tubes or cutting corners result in wall thickness deviations of >5%, and weak areas are prone to rupture under high pressure/high temperature.
Welding/expansion process problems:
Incomplete welding, cold welding or mismatched expansion tube sizes cause stress concentration or sealing failure, leading to leakage.
4. Stress and operating environment factors
Thermal stress and mechanical stress:
Uneven distribution of the medium in the pipe (such as unreasonable gas distribution) causes temperature difference stress beyond the material tolerance range, causing cracks.
High pressure environment (50% over design pressure) causes pipe deformation or microcrack expansion.
High temperature degradation:
When the long-term operating temperature is greater than 500℃, the strength and corrosion resistance of materials such as 316L will decrease significantly, accelerating failure.
5. Inadequate surface treatment and maintenance
Foreign matter or corrosion products in the pipe are not cleaned in time, and the residue grinds the inner wall to cause damage.
After the surface passivation film is destroyed (such as mechanical scratches), the exposed base metal accelerates oxidation and rusting.
From these aspects of analysis, it is known that the failure of stainless steel heat exchange tubes should be systematically prevented from three aspects: material selection optimization, process control, and environmental monitoring to ensure the long-term stable operation of the equipment.
What factors cause the failure of stainless steel heat exchange tubes?
By: mxgy,
Common faults of stainless steel heat exchange tubes, such as corrosion, scaling, material and manufacturing defects, etc., are mainly caused by multiple factors such as material defects, operating environment, and process operation.
1. Corrosion problems
Medium corrosion:
Acidic/alkaline media (such as acid and alkali solutions in chemical production) directly corrode the tube, causing thinning or perforation of the tube wall.
When the chloride ion concentration is ≥500ppm, austenitic stainless steels such as 316L are prone to pitting or intergranular corrosion, accelerating material failure.
Electrochemical corrosion:
Other metal dust (such as iron filings) or pollutants adhere to the tube wall, forming micro-batteries in a humid environment, causing local corrosion.
2. Scaling and clogging
Scale (calcium and magnesium salt deposition) or dirt (organic/particulate accumulation) adheres to the inner wall, reducing heat transfer efficiency and increasing the risk of local corrosion.
3. Material and manufacturing defects
Uneven tube wall:
Poor quality tubes or cutting corners result in wall thickness deviations of >5%, and weak areas are prone to rupture under high pressure/high temperature.
Welding/expansion process problems:
Incomplete welding, cold welding or mismatched expansion tube sizes cause stress concentration or sealing failure, leading to leakage.
4. Stress and operating environment factors
Thermal stress and mechanical stress:
Uneven distribution of the medium in the pipe (such as unreasonable gas distribution) causes temperature difference stress beyond the material tolerance range, causing cracks.
High pressure environment (50% over design pressure) causes pipe deformation or microcrack expansion.
High temperature degradation:
When the long-term operating temperature is greater than 500℃, the strength and corrosion resistance of materials such as 316L will decrease significantly, accelerating failure.
5. Inadequate surface treatment and maintenance
Foreign matter or corrosion products in the pipe are not cleaned in time, and the residue grinds the inner wall to cause damage.
After the surface passivation film is destroyed (such as mechanical scratches), the exposed base metal accelerates oxidation and rusting.
From these aspects of analysis, it is known that the failure of stainless steel heat exchange tubes should be systematically prevented from three aspects: material selection optimization, process control, and environmental monitoring to ensure the long-term stable operation of the equipment.
