Porthole design is too large (especially for low profile extrusion ratio) of aluminum square bar, so squeeze pressure is reduced, thereby reducing the welding force. Recommendation from the edge of the vent hole extrusion cylinder wall at least 6-10mm distance. Shunt hole course selection and diversion structure of the bridge would be better considered together. 2. welding chamber volume is too shallow or too small, can not form a sufficient hydrostatic pressure. Reasonable under guarantee core rigidity and strength of the premise, to increase the volume of welding chamber. Welding chamber can be increased cross-sectional area of ??Shandong Aluminium square bar supplier, may also increase the height of the welding chamber. Extrusion temperature is too high. (See analysis of technological aspects of) the quality and composition 5. Process 1 / rod casting rod aspects prone to internal defects in the (difficult deformation zone) weld hollow sections. Mg, Si, and high total Fe content is too high will exacerbate bad welding, it is recommended Mg, Si 0.7% of the total in the range of -0.9%, Fe content of less than 0.15% of available good quality welds. Specializing in the production of aluminum square bar manufacturers, aluminum square bar, rolls supplied by Alcoa Aluminum Co., Ltd. Jinan rolls. Jinan Heshun Aluminum Co. (www.jnhsly.com) strong, credible, in Jinan, Shandong aluminum products industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead rolls in aluminum and you hand into the brilliant, for a better future!