If the used high frequency tube mills refers to the chemical composition and mechanical properties of welded tube blanks that require certain inspection methods to be known as invisible defects; then, those defects that can be seen only by vision are called tube blanks. Overt defect.

The dominant defects of the welded tube blank of the used high frequency tube millsgenerally include cracked edges, broken edges, sawtooth, pitting, scratches, roll marks, dark spots, edge burrs, sickle bends, wrinkles, waves, edge warping, and points. Layers, warped skins, pinholes, sticky rolls, soft spots, rust, oxide layers, towers, loose rolls, etc. Let me introduce you to the causes of cracked edges and the effect of cracked edge billets on welded pipes.

Pitted noodles

The pitted surface refers to the small pits on the surface of the tube blank. If the number of pits is small and scattered, it is defined as pitting. If there are many pits and densely integrated, it is defined as pitted surface.

Causes of pitted noodles:

(1) The tube blank is corroded.

(2) Severely corroded steel strips are cold rolled after pickling, and the rust pits become small pits.

(3) The pickling is not clean, part of the rust is pressed into the surface of the plate during cold rolling, and then the rust falls and forms small pits.

(4) The oxide scale is pressed in during hot rolling.

The effect of pitting on the quality of welded pipe:

The pitting surface mainly affects the surface quality of the welded pipe, and it is an unacceptable defect for users who need to perform high-requirement surface treatments (chrome plating, nickel plating, electrophoresis, powder spraying) and users of middle and high-end furniture pipes.

About the used high frequency tube mills welded pipe billet defects (2) Introduction to the pitting surface, and the impact of the pitting surface on the quality of the welded pipe, I hope it can help you.