Causes and Solutions for Cracks In Seamless Steel Pipes
Date:2019-11-07 keywords:seamless steel pipe,cracks
Reasons for cracks in seamless steel pipes:
1. The crack traverses the thickness direction of the slab. The crack in the central equiaxed grain region is a curved fine crack along the grain boundary. The crack on the inner arc side is generally a straight crack in the crack, and the crack on the outer arc side is generally along the crystal crack.
2. The crack along the grain boundary is a stress crack, and the crack is a crack that breaks through the grain and is the result of external force.
What do you need to do to resolve this crack?
1. Improve the accuracy of the arc of the casting machine, avoid excessive stress on the solid-liquid interface at the initial stage of solidification, and prevent cracks along the grain boundary.
2. Forced cooling is achieved by appropriately increasing the casting speed and increasing the amount of cooling water, increasing the water flow rate, and lowering the water temperature within a certain range.
3. Strictly control the composition of steel grades, especially the control of carbon content.
4. Increase the electromagnetic stirring of continuous casting. The superheat of the medium-clad steel is controlled below 40 °C.