Q345D seamless steel pipe cannot use magnetic particle inspection for non-magnetic raw materials such as martensitic stainless steel angle steel, copper and aluminum, but can be inspected by infiltration inspection method. The key of Q345D seamless steel pipe penetration detection method is color detection and fluorescence detection.


1. Coloring and flaw detection A layer of bright red additive is applied to the surface of the cleaned stainless steel angle steel. After a certain period of time, the additive with better fluidity and water permeability will penetrate into the defects of the surface layer of Q345D seamless steel pipe, and then Then wipe the welding surface clean, and apply a layer of milky white indicating liquid on the welding surface. When a bright red pattern oozes out from the milky white bottom, it indicates that there is a defect there.


2. The mechanism of this method is to use the ultraviolet light emitted by the liquid mercury quartz stone lamp to excite optical materials (such as magnesium oxide powder soaked in mineral oil), so that it emits light green fluorescence. , Use these characteristics to check the defects of the surface layer of Q345D seamless steel pipe. The specific method is to apply the fluorescent liquid on the surface of the Q345D seamless steel pipe. If the welding surface is defective, the fluorescent liquid can quickly penetrate into the crack because of its strong fusion ability, and then wipe the surface of the Q345D seamless steel pipe. It is clean and directly illuminated with a liquid mercury quartz stone lamp in a dark room. At this time, the luminous powder that penetrates into the defect will shine under the action of ultraviolet rays, and the defect will be revealed.


Color flaw detection and fluorescent flaw detection are mainly used to check the surface defects of Q345D seamless steel pipes or the tightness of Q345D seamless steel pipes. Non-permanent magnetic materials such as stainless steel plate, copper, aluminum and aluminum-magnesium alloy, these two methods are commonly used to check the surface defects of Q345D seamless steel pipe.


When the Q345D seamless steel pipe is in production, the operating table should be kept clean and free of dirt. If there is any, it should be cleaned up immediately. What will happen to the Q345D seamless steel pipe when the Q345D seamless steel pipe manufacturer in Wuxi City shares with you today?


The total surface area of the Q345D seamless steel pipe after emptying has increased, while the area of the inner surface has decreased. Therefore, a neutralized layer will be generated between the inner and outer layers. The layers have increased the area, but the outer layer is greatly improved. Inner surface layer and neutralization layer, the inner surface layer is greatly reduced.


The above transformation characteristics of each layer area of Q345D seamless steel pipe during air drawing endanger the unbalanced deformation of metal materials. One of its advantages is that the widening of each layer along the wall thickness is of course not consistent. Of course, the outer surface of the Q345D seamless steel pipe is the least, and the inner surface of the Q345D seamless steel pipe is larger, and the middle layers are of course widened. Gradually lift from the outer layer to the inner surface layer. The second characteristic is that due to the comprehensive relationship, each layer of the Q345D seamless steel pipe cannot be widened differently during deformation, so the layers must restrict each other.


Because the metal material of the surface layer is naturally wider than the metal material of the inner layer, the surface layer must be subject to the restriction effect of the inner layer during deformation, and its specific widening ratio is of course widened. Conversely, the widening of the inner layer is blocked by the surface layer, and its specific widening ratio is of course small, while the thickness is increased.