Scar defects in hot-rolled seamless steel pipes exist on the inner surface of the pipe, similar to pits the size of soybean grains, and most of the scars contain foreign objects that are gray brown or gray black in color. The influencing factors of internal scarring include: deoxidizer, blowing process, core rod lubrication, and other factors. Let's take a look at how to control the inner surface defects of seamless steel pipes with the help of the seamless steel pipe manufacturer editor:

1. Deoxidizer

The oxide is required to be in a molten state during the pre threading of the core rod. Its strength and other strict requirements.  

1) The particle size of the deoxidizer powder is generally required to be around 16 mesh.  

2) The content of sodium stearate in the deoxidizer should be above 12% to ensure that it can burn fully in the capillary cavity.  

3) The amount of oxide removal agent sprayed is determined based on the surface area inside the capillary tube, generally ranging from 1.5-2.0g/dm2. The amount of oxide removal agent sprayed varies depending on the diameter and length of the capillary tube.