Steel box column is a square tubular load-bearing member composed of four steel plates. It is generally rectangular and square. Because of its high stiffness, light weight and hollow concrete, it forms a special SRC structure. It has good bearing axial pressure, bending distance and horizontal lateral force, and is widely used in high-rise and super-high-rise buildings.Three dimensional steel structure [stock code 832621] has nearly 20 years of steel structure manufacturing experience, and has unique experience in box column manufacturing. Today, I share with you what matters should be paid attention to when welding box steel column. 

 1、 Welding rod is used for box steel column welding, generally covered electrode is used for manual arc welding, and C02 protection can be used for semi-automatic welding.　　

 2、 In CO2 gas shielded arc welding, the current density (current value on unit wire section) should be large enough to make the arc reach the particle transition state.If possible, the fusion between welding passes and between weld bead and groove edge shall be ensured.  

3、 The welding sequence of column column splicing points is mainly to avoid the column deflection caused by uneven contraction of weld seam on the symmetrical side of column section, control the overall dimension of structure, but at the same time, minimize the welding constraint and prevent welding cracks. 　　

 4、 The welding sequence of beam column and beam beam connection joints is usually H-shaped and box shaped.The hybrid connection form of bolt welding is often used. When installing steel structure, bolt first and then weld. The welding sequence of flange is generally welding the lower flange first and then welding the upper flange. If the thickness of flange plate is greater than 30 mm, the upper and lower flange should be welded alternately.