焊接结构机床件的残余应力测试研究

Residual stress testing research of welding lathe bed

焊接机床床身凭借其设计制造过程周期短、效率高、绿色环保、柔性高、价格成本低等显著优势,具有很好的应用前景,将成为床身的发展趋势,近年来以钢板焊接结构代替铸铁件的趋势不断扩大。研究测试了国内外不同焊接结构机床件的残余应力,结果表明,所测床身的焊缝数量比较多,其最大残余应力为274.4 MPa;滑鞍的结构尺寸较长(620 mm×2 700 mm×252 mm),属于矮长件,焊缝较长、筋板较多,其最大残余应力为300.6 MPa;立柱的焊缝和筋板均相对较少、结构尺寸差异小,其最大残余应力为154.9 MPa;所测国外某滑鞍的最大残余应力为129.8 MPa,该滑鞍具有优良的结构设计、焊缝较少较短;优化结构设计、筋板布局和焊接工艺,采用合理的结构尺寸,减少和缩短焊缝是降低焊接结构机床件初始应力、获得高精度机床产品的基础。

In recent years,the trend of steel plate welded structure replacing cast iron is expanding.Welding bed has a very good application prospects due to the distinct advantages of shorter design and manufacturing cycle,higher efficiency,green environmental protection,higher flexibility and lower costs and so on.In this studies,the residual stress of different welded structure beds was tested.Results showed that the measured bed has a large amount of weld seam,and the maximum residual stress is 274.4 MPa.The structural dimensions of the sliding saddle are relatively longer(620 mm×2 700 mm×252 mm),which belongs to the short long piece.It has the longer weld seam and more steel plate,and the maximum residual stress is 300.6 MPa.The weld seam and steel plate of the column are relatively less,and the structural size difference is smaller.The maximum residual stress of the column is 154.9 MPa.The maximum residual stress of the foreign sliding saddle is 129.8 MPa,which benefited from the excellent structural design and less and shorter weld welding seams.By optimizing the structural design,the layout of the ribs,the welding process,and reducing and shortening the weld seams,which is the basis of reducing the initial stress of welded structural machine tools and obtaining high-precision machine tools.