Knowing that galvanized seamless steel pipes will have scars, what are these scars? These scars are small pits of different sizes like soybean particles, with gray-brown or gray-black foreign bodies in them. So, how to effectively control the scar of galvanized seamless steel pipe? This article introduces eight methods that can effectively control the scar of galvanized seamless steel pipe.

(1) The particle size of the deoxidizer powder is generally around 16 meshes.
(2) According to the inner surface area of galvanized seamless steel pipe, the spraying amount of deoxidizer is generally 1.5-2.0g/dm2. The amount of deoxidizer has different requirements for pipes of different diameters and lengths.
(3) The purging time is adjusted according to the straightness and length of the pipeline, and it is the standard that there is no suspended metal oxide in the pipeline that needs to be blown out again.
(4) The lubricating effect of the mandrel is not good or the lubricating temperature of the mandrel is too low, which will cause internal scabs. In order to increase the temperature of the mandrel, a water cooling method can be used.
(5) The content of sodium stearate in the deoxidizer should be greater than 12%, so that it can fully burn in the inner cavity of the galvanized seamless steel pipe.
(6) Strictly control the temperature of the mandrel to ensure that the surface temperature of the mandrel is 80-120℃ before spraying the lubricant, and the temperature of the mandrel cannot exceed 120℃ for a long time to ensure that the lubricated surface of the mandrel is dry and dense before the puncture. The operator should frequently check the lubrication of the mandrel.
(7) The nozzle height should be adjusted according to the diameter of the galvanized seamless steel pipe to ensure good alignment. Clean the nozzles once per shift, and take out the nozzles for cleaning when the machine is shut down for a long time. In order to ensure the uniform cleaning of the deoxidizer on the inner wall of the pipeline, an optional device is used at the position where the deoxidizer is blown off, and it is equipped with a rotary air pressure.

(8) The injection pressure should match the diameter and length of the pipeline to ensure strong purging and sufficient combustion, and the airflow of the galvanized seamless steel pipe should not blow away the unfinished oxide scavenger.

       Under normal circumstances, in the industrial production process of galvanized seamless steel pipes, insufficient welding occurs when hot-melt butt welding galvanized seamless steel pipes, mainly due to insufficient travel of the welding fixture and excessive speed of the fixture during butt welding. Caused. Common situation analysis mainly includes the following two points:
Before the two connectors are butted, the gate should be ground with a milling cutter, and then a pre-welding crash test is performed. After the collision, there should be a certain stroke margin on the stroke rod of the fixture, and the stroke margin should not be less than 200mm. If this is not noticed during the welding process, the travel margin of the fixture is not enough, the butt surface after welding is good, but the fusion of the two butts is actually not complete enough, resulting in welding errors. This is a common, hard-to-detect problem in butt welding.