Condenser Titanium Tube Welding Repair Process

In the process of condenser titanium tube welding, found that the weld oxidation is more costly, more pores, coloring inspection of apricot has a lot of pores and cracks, irrigation inspection there are more than 50 leaks, due to the titanium tube plate belongs to a more active metal, the reparability is poor, according to the instructions required to repair should not be more than three times. For this situation, the company to appear on the problem of serious and careful analysis, first find out the causes of various quality problems, and find out the corresponding countermeasures and effective remedies, and then the hands of the patch welding practice and finally go through the formal manual welding repair, to ensure that the second time the success of the second weld.

Cracked patch welding:
The key is to remove the crack to the root. After the discovery of cracks should first use a smooth grinder and reamer head on the cracks for a thorough clear, otherwise patch welding after the depth of the crack 丨U * can be slowly extended after a few hours after the rare surface, resulting in new cracks. The cracked area after gouging and patching is inspected by PT to confirm that it has been completely removed before welding: the same internal ketone is used to clean the area before welding; the welding wire is not added when welding. The key to crack patching is to control the temperature to prevent 丨h titanium tube oxidation overcooking, patching the welded joints and other thoroughly cooled PT inspection, and should be again after 24 hours of PT inspection to determine whether there is a delay in the generation of cracks.

Patch welding of porosity:
The generation of porosity is mainly caused by the presence of impurities between the titanium tube and the tube plate, and the main effort should be put on the cleaning of the tube plate before welding, so that the generation of porosity can be effectively avoided. The repair of air holes generally does not require the addition of welding wire. Patch welding operation should be stable, tungsten electrode tip directly aligned with the air hole area arc, to be melted after the air hole immediately stop the arc, stop the arc when the attenuation time should be greater than 4s, stop the arc / T; argon arc handle do not immediately take away, the application of argon on the patch welding point to cool down for a few seconds and then the argon arc handle to take away. After replacing the welding parts should be bright white, with a metallic luster, such as the color blue or silver gray, it shows that the temperature is too high when replacing the welding, PT inspection is easy to find crack defects.

Welding tumor and the treatment of unfused defects:
The reason for this is mainly due to the titanium tube expansion is not tight or 0 dynamic welder coaxiality is not enough, the welding gun deviates from the centerline of the titanium tube. Welding pain and unfused defects are generally deeper in location, some welding tumor in the place of 3.5mm from the mouth of the tube, make-up welding position is more difficult, and technology due to the thin titanium tube, make-up welding is easy to burn the titanium tube, the formation of the formation of the more complementary, the location of the more paddle f. Li, the more difficult to make up for the welding of the results. Before welding a defective weld lump, the weld lump should be ground off with a carbide rotary file, and then the tube should be reexpanded with a tube expander and cleaned with an internal ketone before welding. The filler welding on the operator's welding technology requirements are relatively high, in the operation to fully grasp the "stable, accurate, ruthless" operating principles, that is, the operation should be stable, wire feed to be accurate, judgment to be decisive. In the complementary welding operator holding the welding torch to lean on the tube plate, in order to avoid the torch is not stable, the arc burns other parts of the titanium tube. In the wire must be sent to each drop of wire accurately to the defects, judgment to send the part of the wire to be decisive, + can be hesitant, in order to prevent the temperature is too high caused by oxidation. Some defects from the tube plate surface curve farther, filler welding wire feeding difficulties, in order to prevent the sending pattern is not timely to the defects will be burned larger and larger, you can first melt a drop of wire in the edge of the defects, and then filler welding.