Pre-honed tube is made of cold drawn seamless tube, also we can calle it ready to honed tube,It’s widely used in hydraulic system with precision steel tube, hydraulic press with precision steel tube, shipbuilding with steel tube, hydraulic machinery,hydraulic cutting machine, hydraulic equipment, hydraulic tubing, engineering machinery.
Heat Treatment Delivery Condition of Pre honed tube
Cold finished (hard) BK(+C)
Tubes do not undergo heat treatment following the final cold forming and, thus, have a rather high resistance to deformation
Cold finished (soft) BKW(+LC)
The final heat treatment is followed by cold drawing involving limited deformation. Appropriate further processing allows a certain degree of cold forming (e.g. bending, expanding)
Cold finished and stress-relieved annealing BKS(+SR)
Heat treatment is applied following the last cold forming process. Subject to appropriate processing conditions, the increase in the residual stresses involved enables both forming and machining to a certain degree.
Annealed GBK(+A)
The last Cold forming process is followed by annealing in a controlled atmosphere.
Normalized NBK(+N)
The last cold forming process is followed by annealing above the upper transformation point in a controlled atmosphere.