API 5L Straight 6" ERW Stainless Steel Pipe Liquid Transport

Straight Seam High Frequency For Liquid Transport Uses 6"ERW Steel Pipe

The application of this method can eliminate stress, soften and refine microstructure, and improve the comprehensive mechanical properties of heat-affected zone.Up to now, advanced ERW units in the world have generally adopted this method to treat the welding seam, and good results have been obtained.

According to the different welding technology of high frequency straight seam welded steel pipe can be divided into straight seam high frequency resistance welded steel pipe and straight seam high frequency induction welded steel pipe.The forming process generally adopts the rolling cold forming method.The diameter of high frequency straight seam welded steel pipe is generally small, generally below 660mmor 26in outside diameter.

It is necessary to take measures to make it uniform and consistent.The high frequency welding thermal process of ERW steel tube results in the gradient of temperature distribution near the edge of the tube blank, and forms the characteristic areas such as melting zone, semi-melting zone, superheated structure, normalizing zone, incomplete normalizing zone and refiring zone.Among them, the austenite grains in the overheated area grow rapidly due to the welding temperature above 1000℃, and the hard and brittle coarse grain phase will be formed under the cooling condition. In addition, the existence of temperature gradient will produce welding stress.In this way, the mechanical properties of the weld area are lower than that of the base metal.