Reasons for cracking of cold drawn seamless tubing

The reasons for cracking of cold drawn seamless tubing may include the following aspects:

1. Material problem.
The quality of the raw materials is not up to standard. For example, the hardness, strength, toughness and other properties of the material do not meet the usage requirements, or there are defects such as inclusions and bubbles in the material. These will affect the performance of the material and cause the steel pipe to crack.

a. Inclusion problem: Inclusions are a form of impurities in cold-drawn seamless tubes. When the volume of inclusions is too large, it will affect the strength and plasticity of the steel pipe, leading to cracks.

b. Bubble problem: Bubbles are formed during the manufacturing process. The presence of bubbles will reduce the strength and stiffness of the material, leading to cracks.

2. Manufacturing process problems.
a. Problem of excessive cold drawing: When cold drawing is excessive, it will cause the steel pipe to crack. This is because excessive cold drawing causes excessive stress inside the steel pipe, which leads to cracking.
b. Improper control of the steel pipe stretching process: Improper control during the steel pipe stretching process will lead to stress concentration, which may lead to cracks.
c. Production process problems: There are unreasonable aspects in the production process, such as traditional methods such as mold aging, which can also cause steel pipes to crack.

3. Processing issues.
Such as uneven stretching, processing speed, pressure, improper use of coolant, etc., these may cause uneven stress inside the steel pipe, thereby forming cracks.

4. Equipment problems. 

Wear and design defects of processing equipment may also cause steel pipes to be unevenly stretched or squeezed during processing, causing stress concentration and leading to cracks.

5. External factors.
If the processing environment conditions are harsh (such as excessive temperature, humidity) or wear and tear, these may cause the cold-drawn steel pipe to crack.

To sum up, there are many reasons for the cracking of cold-drawn seamless tubes, including materials, manufacturing processes, processes, equipment, and external factors. These factors need to be strictly controlled during the processing process to reduce or avoid the occurrence of such defects. 

Tips: ASTM A106 seamless pressure pipe (also known as ASME SA106 pipe) is commonly used in the construction of oil and gas refineries, power plants, petrochemical plants, boilers, and ships where the piping must transport fluids and gases that exhibit higher temperatures and pressure levels.