Steel pipe delivery status
The steel pipe delivery status refers to the state of the steel pipe product after final plastic deformation or heat treatment, which directly affects its mechanical properties and application areas. It is usually necessary to clearly indicate when signing the contract. According to different manufacturing and processing processes, the steel pipe delivery status can be divided into the following types:
·Hot-rolled or cold-drawn (rolled) manufacturing status: direct delivery without heat treatment. Hot-rolled steel pipes have higher strength and are suitable for structural parts and pipelines, while cold-drawn (rolled) steel pipes have higher dimensional accuracy and surface quality.
·Heat treatment status: Steel pipes after heat treatment are divided into the following types according to specific treatment methods:
Quenching state | The steel pipe is heated to above the phase transition point and then cooled rapidly. | Increase hardness and reduce toughness. |
Normalizing state | The steel pipe is heated to above the phase transition point and then cooled naturally (in air). | Improve toughness, suitable for occasions with high toughness requirements. |
Annealing state | The steel pipe is heated and then cooled slowly. | Eliminate stress, make the composition uniform, and improve processing performance. |
Tempering state | After quenching, the steel pipe is heated again and cooled. | Take into account both strength and toughness. |
2. Two ways of delivery by weight
·Actual weight delivery: The product is based on the actual weighing weight at the time of delivery, which is suitable for a more accurate weighing environment.
·Theoretical weight delivery: According to the nominal size of the steel pipe and the density of the steel, the weight is calculated according to the calculation formula. This method is often used for the delivery of large quantities of steel.
Reasonable selection of delivery status can optimize the mechanical properties of steel pipes, meet different engineering requirements, and ensure the reliability and stability of product quality.
