Austempering is a quenching technique. Line pipe manufacturers use this technique to decrease the twisting and splitting of seamless steel pipes. However, manufacturers must base their strategies on the size, hardness, material, and toughness of the seamless tubes. Considering these factors allows pipe fabricators to successfully and effectively utilize the austempering method.  

In addition to the abovementioned factors, manufacturers should also focus on the conditions and deformation requisites. Manufacturers must note the accompanying issues during austempering to strategize the process.  

We have jotted down what pipe producers keep in mind when they choose the austempering technique as one of the heat treatments.  

Context of the temperature and time: 

Manufacturers must choose the temperature and time for austempering the seamless tubes and pipes based on the C-bend of the pipes. They must change all austenite to start the process. They must alter them to lower bainite. At the same time, pipe fabricators should arrange a medium salt bath for the austempered tubes and pipes. The salt bath is the cooling medium in the austempering technique.  

Pipe producers must add a cooling gadget to the medium. Thus, they can keep the temperature from increasing. They can also guarantee the stability of the temperature. Keeping a cooling gadget can influence the quenching quality, affecting the quality of the final product. It is necessary for manufacturers to maintain the temperature of the quenching medium at all times.  

In addition, seamless pipe suppliers must locate and compare the length of the isothermal time during the structural transformation of the seamless conduits. Most likely, the longer it takes, the more diminishing the temperature can be. It means that if engineers fail to cool down the pipes and tubes in time, they may reduce the effectiveness of the same.  

Manufacturers must suitably raise the quenching heating temperature to austemper steel pipes with low hardenability. It helps build the resilience of austenite pipes and tubes. At the same time, it keeps away high temperatures during isothermal procedures.  

Considering the size of seamless conduits:  

Manufacturers must consider the size of the seamless tubes and pipes while austempering them. They should also consider the steel grade constraints. There is one rule that engineers must remember while austempering. They must guarantee that the steel conduits do not experience rapid temperature change during the cooling procedure.  

Rapidly changing the temperature can hamper the grade and the size of the steel pipes. It can also directly affect the character of the isothermal quenching. The viable thickness of the pipes must be around 5mm. The density of the seamless pipes should be below 30mm. Manufacturers should not choose the austempering technique for carbon steel with a concentration of 0.4 to 0.6 percent. Such alloys are unstable for austempering. However, it is totally safe to austemper steel pipes that have more than 0.6% carbon content. 

Some seamless pipe suppliers expose seamless conduits to austempering without tempering them. It allows them to create a piping solution with a relatively thinner wall.  

However, engineers must remember that the interior austenite can change when they retain the pipes. The austenite can turn into martensite for some of the pipe pieces during the air-cooling process. They must temper the metal pipes to eliminate brittleness and increase the stability of the seamless steel tubes. They must lower the tempering temperature in comparison with the isothermal temperature. 

The final thoughts: 

Austempering is one of the complex quenching techniques. However, manufacturers can easily carry out the technique if they follow the proper process. Seamless tube manufacturers choose to austemper to eliminate twisting and splitting of seamless conduits.  

However, it is often not possible for the users to know whether manufacturers perform quenching techniques. They should contact established seamless pipe fabricators. Established manufacturers not only have experience but also know the processes well. Hence, they can ensure whether the users need austempered pipes or not. 

If you are unsure which type of pipes you need, you can discuss it with the manufacturers. They can guide you about which seamless tubes you can choose. It will give you a better idea about which pipes to choose or refrain from when purchasing your seamless tubes.