Knowledge points of high frequency welded pipe

Straight seam high-frequency welded pipe has the characteristics of simple process and continuous production. It is used in civil construction, petrochemical, light industry and other departments. It is mostly used to transport low-pressure fluid or make engineering components and light industrial products. What are the knowledge points of high-frequency welded pipe? , let me introduce to you.

The opening angle refers to the angle between the two edges of the tube blank in front of the extrusion roller. The size of the opening angle is related to the stability of the burning process and has a great influence on the welding and quality. When the opening angle is reduced, the distance between the edges also If the opening angle is too small, the distance from the meeting point to the middle line of the extrusion roller will become longer. As a result, the edge is not squeezed at high temperature, which will reduce the quality of welding and increase power consumption.
Actual production experience shows that the longitudinal position of the guide roller can be moved to adjust the size of the opening angle, usually between 2° and 6°. When the guide roller cannot be adjusted longitudinally, it can be adjusted by using the thickness of the guide ring or pressing down the closed pass. Adjusts the size of the opening corner.
The position of the sensor has a great influence on the welding and quality. When it is far away from the middle line of the extrusion roller, the heating time is long and the heat-affected zone is wide, which reduces the welding and strength. On the contrary, insufficient edge heating will also reduce the welding strength. The inductor should be placed concentrically with the pipe, and the distance between its front end and the middle line of the extrusion roller is approximately equal to or less than the diameter of the pipe.
The placement position of the resistor (magnetic rod) not only has a great influence on the welding and speed, but also has a great influence on the quality. Practice has proved that when the front end of the resistor is just at the middle line of the extrusion roller, the flaring strength and crushing strength Preferably, the geometric dimensions of the welded tube billet and the width and thickness deviation of the tube billet will change the heating temperature and extrusion amount of the edge, and qualified products must meet the standards.
If there are bends, sickle bends and corrugations on the edge of the tube billet, it will deviate from the pass when passing through the forming machine, causing both sides of the strip to bend, and poor adjustment of the rolls will also cause strip deviation or tube billet deformation, which will affect the Poor weld quality or no weldability at all.
Welded pipes for low-pressure fluid transmission are also called ordinary welded pipes, commonly known as clarinet pipes. Galvanized welded pipes for low-pressure fluid transmission are also called galvanized electric-welded steel pipes, commonly known as white pipes. The steel pipe used to protect the wires in the installation project, the straight seam electric welded steel pipe is a steel pipe whose weld seam is parallel to the longitudinal direction of the steel pipe.
The high-frequency welded pipe is based on the principle of electromagnetic induction and the skin effect, proximity effect and eddy current thermal effect of the AC charge in the conductor, so that the steel at the edge of the weld is locally heated to a molten state, and the butt weld is extruded by a roll to achieve crystal indirect High-frequency welded pipe is a kind of induction welding, which does not require weld filler, does not produce welding and spatter, narrow welding and heat-affected zone, beautiful shape, good welding and mechanical properties, Therefore, it is more commonly used in the production of steel pipes.