Cause analysis of slag hanging in steel plate cutting process

Cause analysis of slag hanging in steel plate cutting process

When the steel plate is cut by flame cutting, it mainly depends on the high temperature formed by gas combustion. Through the cutting torch, the material is heated and melted in the local range, so as to achieve the purpose of cutting. However, it is not difficult to find from the characteristics of Q235 and other carbon steel plates that the transition time from liquid state to solid state is often very short, especially when it is separated from a certain temperature range, it will solidify rapidly, thus forming slag.

In the actual steel plate cutting process, the so-called slag hanging is the solid-state melting slag formed due to certain reasons. How can we reduce the formation of slag hanging when using numerical control flame cutting machine? First of all, from the position of slag hanging formation, generally, the slag hanging in flame cutting is divided into upper edge slag hanging and lower edge slag hanging, resulting in different causes of slag hanging.

The slag hanging on the upper edge is mainly on the cutting section of steel plate, especially on the lower part. The main reason for the slag hanging on the upper edge is that the alloy content of the material is too high. Generally, flame cutting is mainly applicable to Q235 carbon steel plate and ordinary carbon steel plate, and low alloy steel plate similar to Q345 can also be applied. However, if the alloy content is too high, slag may hang on the upper edge in steel plate cutting process.

The slag hanging on the lower edge is a very common phenomenon in flame cutting, which mainly produces continuous slag hanging on the lower edge of the cutting section. The causes of similar problems are relatively complex. Generally speaking, when slag is hung on the lower edge of steel plate cutting, check whether the cutting speed is too fast or too slow, the number of cutting nozzle is too small, and the cutting oxygen pressure is too low.

Then judge the excess gas in the preheating flame, rust or unclean oxide skin on the cutting surface of the steel plate may also affect the excessive slag hanging; the height between the cutting nozzle and the workpiece is too large after exceeding, and the too strong preheating flame is also one of the main reasons for slag hanging at the lower edge.