X70M HFW焊管液压胀环法和平板拉伸法试验对比分析

为了准确测量HFW焊管全管体真实屈服强度，设计并制造了液压胀环试验设备，测量了4种不同规格X70M HFW焊管的屈服强度，并与平板拉伸法测量的结果进行了对比。结果表明，无论用哪种测量方法，径厚比越大，HFW焊管的屈服强度越大，对应的屈强比也越大；液压胀环法测量的屈服强度比平板拉伸法测量的屈服强度高15～30 MPa；当应变＜1%时，液压胀环法测得的应力比平板拉伸法测得的应力高

Contrastive Analysis on Hydraulic Ring Expansion Test Method and Flat Tensile Test Method for X70M HFW Pipe

In order to accurately measure the true yield strength of full body of HFW pipe， hydraulic ring expansion equipment was designed and manufactured， and yield strength of 4 specifications X70M HFW welded pipe was measured and compared with the results measured by Flatten Bar test method（FB）. The results showed that no matter using which methods， the higher the diameter-thickness ratio， the higher the yield strength of HFW pipe and the yield ratio； the yield strength measured by Hydraulic Ring Expansion test method（RE） was 15～30 MPa higher than these measured by FB； when the strain was less than 1%， stress measured by RE was higher than these measured by FB.