The selection of equipment for the steel pipe heat treatment production line should be based on the product outline, that is to say, the appropriate equipment should be selected according to the type of steel pipe (seamless pipe or welded pipe), specification, output, etc.
1. The quenching furnace is also called a high-temperature furnace. It is used to heat the steel pipe to achieve austenitization. The choice of furnace type and technical parameters should be compatible with the product outline. The main content of the product outline is output, variety, specification, etc. The heat treatment production line is generally based on the walking furnace type, and other furnace types, such as roller hearth furnaces and induction heating furnaces, can also be used.
2. The cooling device mainly refers to the quenching equipment. The steel pipe is a hollow cylindrical product with a length of several meters to more than ten meters. During the quenching process, how to control the deformation of the steel pipe within a minimum range should be given priority. In addition, the normalizing cooling device is also very important. The device suitable for large batches and uniform cooling is a cooling bed with forward and reverse chains.
3. The tempering furnace or low temperature furnace is mainly used for tempering the quenched steel pipe, and can also be used for other treatment processes below the critical temperature of the steel pipe, such as recrystallization annealing, stress relief annealing, etc. The furnace type should be consistent with the quenching furnace type, mostly walking furnace type.
4. In order to ensure the geometric dimension accuracy of the steel pipe after heat treatment, the sizing machine is mainly the outer diameter and ovality. Some heat treatment lines sizing the steel pipe after tempering. The following factors should be considered in the selection of the sizing machine: the rolling accuracy of the steel pipe, and the deformation (ellipticity) of the steel pipe after quenching. If the rolling accuracy and ovality can meet the standard or the requirements of the next process, it is not necessary to set the diameter machine.
5. The steel pipe after heat treatment by the straightening machine will inevitably be deformed, that is, the bending and ellipticity will increase, so the straightening process is essential. The straightening machine is generally installed after the tempering furnace, and the steel pipe is straightened after it leaves the tempering furnace. It is generally called "hot straightening" or "warm straightening". This kind of straightening with temperature has a good effect, especially for high-strength products. In addition, some products have requirements for straightening temperature. For example, HS corrosion-resistant steel grades in oil casings do not allow cold straightening, while "hot straightening" has minimum straightening temperature requirements.
The heat treatment production line can also be equipped with a cold straightening machine as needed, which can further improve the straightening effect of the steel pipe. In addition, it can straighten the steel pipe that does not pass through the tempering furnace.
In addition, after the heat treatment (quenching) of the steel pipe, sometimes bending occurs at the end of the steel pipe, which cannot be completely eliminated by straightening with a skewed roll straightening machine. In this way, it is necessary to equip a pressure straightening machine for end straightening
6. The steel pipe heat treatment production line with high non-destructive testing output should be equipped with online non-destructive testing equipment. The commonly used testing method is ultrasonic. In order to enhance the testing effect, other testing methods can also be used in conjunction with it, such as eddy current testing.
7. In addition to the main equipment, other heat treatment production lines must also be equipped with auxiliary devices, such as cooling beds, collection chains, transport rollers, etc. These devices are very important for the smooth execution of production organization and technology.
Furnaces suitable for heat treatment of steel pipes mainly include stepping type, roller hearth type and induction heating type. For large-scale production, it is more reasonable to adopt a walking furnace type, but the investment is large; the output of the roller hearth type and induction heating type furnace type is low, and the cooling method and automatic production line are limited, but the investment is small. In fact, the choice of furnace type is closely related to the variety, specification, output and technical requirements of the steel pipe. Some large-scale steel pipes can also use other suitable furnace types due to their low output.
1. The quenching furnace is also called a high-temperature furnace. It is used to heat the steel pipe to achieve austenitization. The choice of furnace type and technical parameters should be compatible with the product outline. The main content of the product outline is output, variety, specification, etc. The heat treatment production line is generally based on the walking furnace type, and other furnace types, such as roller hearth furnaces and induction heating furnaces, can also be used.
2. The cooling device mainly refers to the quenching equipment. The steel pipe is a hollow cylindrical product with a length of several meters to more than ten meters. During the quenching process, how to control the deformation of the steel pipe within a minimum range should be given priority. In addition, the normalizing cooling device is also very important. The device suitable for large batches and uniform cooling is a cooling bed with forward and reverse chains.
3. The tempering furnace or low temperature furnace is mainly used for tempering the quenched steel pipe, and can also be used for other treatment processes below the critical temperature of the steel pipe, such as recrystallization annealing, stress relief annealing, etc. The furnace type should be consistent with the quenching furnace type, mostly walking furnace type.
4. In order to ensure the geometric dimension accuracy of the steel pipe after heat treatment, the sizing machine is mainly the outer diameter and ovality. Some heat treatment lines sizing the steel pipe after tempering. The following factors should be considered in the selection of the sizing machine: the rolling accuracy of the steel pipe, and the deformation (ellipticity) of the steel pipe after quenching. If the rolling accuracy and ovality can meet the standard or the requirements of the next process, it is not necessary to set the diameter machine.
5. The steel pipe after heat treatment by the straightening machine will inevitably be deformed, that is, the bending and ellipticity will increase, so the straightening process is essential. The straightening machine is generally installed after the tempering furnace, and the steel pipe is straightened after it leaves the tempering furnace. It is generally called "hot straightening" or "warm straightening". This kind of straightening with temperature has a good effect, especially for high-strength products. In addition, some products have requirements for straightening temperature. For example, HS corrosion-resistant steel grades in oil casings do not allow cold straightening, while "hot straightening" has minimum straightening temperature requirements.
The heat treatment production line can also be equipped with a cold straightening machine as needed, which can further improve the straightening effect of the steel pipe. In addition, it can straighten the steel pipe that does not pass through the tempering furnace.
In addition, after the heat treatment (quenching) of the steel pipe, sometimes bending occurs at the end of the steel pipe, which cannot be completely eliminated by straightening with a skewed roll straightening machine. In this way, it is necessary to equip a pressure straightening machine for end straightening
6. The steel pipe heat treatment production line with high non-destructive testing output should be equipped with online non-destructive testing equipment. The commonly used testing method is ultrasonic. In order to enhance the testing effect, other testing methods can also be used in conjunction with it, such as eddy current testing.
7. In addition to the main equipment, other heat treatment production lines must also be equipped with auxiliary devices, such as cooling beds, collection chains, transport rollers, etc. These devices are very important for the smooth execution of production organization and technology.
Furnaces suitable for heat treatment of steel pipes mainly include stepping type, roller hearth type and induction heating type. For large-scale production, it is more reasonable to adopt a walking furnace type, but the investment is large; the output of the roller hearth type and induction heating type furnace type is low, and the cooling method and automatic production line are limited, but the investment is small. In fact, the choice of furnace type is closely related to the variety, specification, output and technical requirements of the steel pipe. Some large-scale steel pipes can also use other suitable furnace types due to their low output.
