diff --git a/HJGL_DS/FineUIPro.Web/HJGL/WeldingManage/JointInfoEdit.aspx.cs b/HJGL_DS/FineUIPro.Web/HJGL/WeldingManage/JointInfoEdit.aspx.cs
index 63548d3..c218ce5 100644
--- a/HJGL_DS/FineUIPro.Web/HJGL/WeldingManage/JointInfoEdit.aspx.cs
+++ b/HJGL_DS/FineUIPro.Web/HJGL/WeldingManage/JointInfoEdit.aspx.cs
@@ -918,7 +918,7 @@
                     var isoInfo = BLL.HJGL_PW_IsoInfoService.GetIsoInfoByIsoInfoId(this.ISO_ID);
                     if (isoInfo != null)
                     {
-                        if (joty.JOTY_Group == "1")
+                        if (joty.JOTY_Group == "1")//对接
                         {
                             if (!string.IsNullOrEmpty(isoInfo.Joty_B_Rate))
                             {
@@ -937,7 +937,7 @@
                                 this.drpJOT_QualifiedLevel.SelectedValue = BLL.Const._Null;
                             }
                         }
-                        else if (joty.JOTY_Group == "2")
+                        else if (joty.JOTY_Group == "2")//角焊缝（承插）
                         {
                             if (!string.IsNullOrEmpty(isoInfo.Joty_C_Rate))
                             {
@@ -955,8 +955,26 @@
                             {
                                 this.drpJOT_QualifiedLevel.SelectedValue = BLL.Const._Null;
                             }
+
+                            //焊口号前自动加C
+                            string jointNo = this.txtJointNo.Text.Trim();
+                            if (!string.IsNullOrEmpty(jointNo))
+                            {                                
+                                if (char.IsDigit(jointNo[0]))
+                                {
+                                    this.txtJointNo.Text = "C" + jointNo;
+                                }
+                                else
+                                {
+                                    this.txtJointNo.Text = "C" + jointNo.Substring(1);
+                                }
+                            }
+                            else
+                            {
+                                this.txtJointNo.Text = "C";
+                            }
                         }
-                        else if (joty.JOTY_Group == "3")
+                        else if (joty.JOTY_Group == "3")//支管连接焊缝
                         {
                             if (!string.IsNullOrEmpty(isoInfo.Joty_D_Rate))
                             {
@@ -974,6 +992,24 @@
                             {
                                 this.drpJOT_QualifiedLevel.SelectedValue = BLL.Const._Null;
                             }
+
+                            //焊口号前自动加D
+                            string jointNo = this.txtJointNo.Text.Trim();
+                            if (!string.IsNullOrEmpty(jointNo))
+                            {
+                                if (char.IsDigit(jointNo[0]))
+                                {
+                                    this.txtJointNo.Text = "D" + jointNo;
+                                }
+                                else
+                                {
+                                    this.txtJointNo.Text = "D" + jointNo.Substring(1);
+                                }
+                            }
+                            else
+                            {
+                                this.txtJointNo.Text = "D";
+                            }
                         }
                     }
                 }