Many people may not know that scars will also appear in the shaped steel pipe, so what are these scars? These scars are small pits like soybean grains of different sizes, which will appear grayish brown or grayish black foreign bodies, then, how should we effectively control the scar in the shaped tube? Here are eight ways to effectively control shaped tube scars.

(1) The particle size of the deoxidizer powder is generally required to be about 16 mesh.
(2) According to the surface area of the special-shaped tube to determine the amount of deoxidizer blowing, generally 1.5-2.0g/dm2, different diameters, lengths of pipe blowing oxide dose is different.
(3) The purging time should be adjusted according to the direct and length of the pipe, with no suspended metal oxides in the pipe being blown out as the standard.
(4) The mandrel lubrication effect is not good or the mandrel lubricant temperature is too low, which will produce internal scarring. In order to increase the temperature of the mandrel, a water cooling method can be adopted.
(5) The content of sodium stearate in the oxide removal agent should reach more than 12% so that it can be fully burned in the special-shaped tube cavity.
(6) Strictly control the temperature of the mandrel, ensure that the surface temperature of the mandrel before spraying the lubricant is 80-120 ° C, and the temperature of the mandrel can not be higher than 120 ° C for a long time, so as to ensure that the lubricant on the surface is dry and dense before pre-wearing. The operator should check the lubrication status of the mandrel frequently.
(7) The nozzle height should be adjusted according to the diameter of the shaped pipe to ensure good alignment. The nozzle should be cleaned once per shift, and the nozzle should be removed for cleaning after a long downtime. In order to ensure that the oxide removal agent is evenly purged in the inner wall of the pipe, an optional device is used in the spray removal station and equipped with rotating air pressure.
(8) The injection pressure should be matched with the diameter and length of the pipe to ensure that the purge is strong and the combustion is sufficient, and the incomplete combustion of the oxide can not be blown away by the air flow from the special-shaped pipe.