Causes of scratches on cold drawn seamless steel tubes

1. The inner surface of the draft is not smooth, cracked or metallized.
2. The transition part of the hammerhead has angular edges and wear tools.
3. The residual iron oxide scale of the cold drawn seamless steel tube blank is not acid cleaned.
4. When the lubricant is applied, the phosphating and saponifying processes are not properly operated.
5. The inner and outer molds have been damaged or worn seriously.
6. The intermediate annealing is uneven and the deformation is insufficient.