The welding specification parameters are as follows: Welding position Tensile strength fracture bending (90 degrees) Anti-intergranular corrosion method (T-test qualified) (Mpa) Face Bend Back Bend (90 degrees) Back Bend (90 degrees) 1 587 Qualified and qualified 2 617 Qualified and qualified 2 616 Qualified and qualified Hardness value Welding position hardness inspection range ( Base material heat affected zone fusion line weld Vertical fixation Horizontal fixation 166/165 165/175 160/167 167/186 175/185 186/190 176/170 172/178 HV5) HV5 test method): Welding metallographic structure 5.3 Surface forming and root penetration good A+δ, F The use of flux-cored wire, the back is not filled with argon welding, the operation is simple and convenient, eliminating a series of argon-filled protection facilities and auxiliary labor, high efficiency, low cost, especially in the high-altitude operation, its superior performance is more significant. Compared with the argon filling on the back of the normal solid wire, the first layer of bottom sealing can increase the efficiency by 1 to 2 times and the cost is low. Compared with argon filling on the back side, it saves 2-3 times of argon and saves all auxiliary argon protection facilities. Horizontal fixed φ Vertically fixed φ Previous page Safety Shoes,Casual Style Safety Shoes,Fabric Safety Shoes Work Footwear Co., Ltd. , http://www.nssafeshoe.com
(mm) (mm) (A) (V) (L/ml) When the normal cover is a simple argon arc welder (AX-320 DC welder), the polarity is positive, that is, the torch is negative, the workpiece When the arc is triggered, the contact arc is used (short-circuit arc), and the action is fast when the arc is triggered to prevent damage to the tungsten and weld tungsten.
C0.085 Mn1.12 Si0.55 Ni9.8 Ti0.028 Nb0.65 Cr19.00 S0.016 P0.018
5.2 Metallographic test results
The bottom of the back cover is well fused, the argon gas is evenly protected, and there is no oxidation condition, and the appearance is beautiful.
6. Conclusion
Weld chemical composition:
2 2~2.5 75~85 17~18 6~8 60~70 50~60 2 2~2.5 75~90 17~18 6~8 60~70 50~60 5~10mm arc starting. After the arc is ignited, it stays for about 5~10s. After the molten pool with the same width as the welded seam is formed, the welding distance can move forward. No welding wire is added or added to the overlap to ensure uniform width and uniformity of the weld. At 1/2, press it inwardly to increase the penetration of the root and prevent the recess. The welding wire should be regularly fed into and removed from the molten pool. The distance from the wire should be taken out to ensure that the end of the wire is in the argon protection zone to avoid oxidation of the tip and affect the protection effect. The arc starting welding is started at a position of about 10 mm ahead of 6 o'clock. Leading arc welding is to prevent the joints from overlapping, and the second layer and the first layer joint are staggered. 75~85 degrees, the angle between the welding wire and the surface of the weldment is 15~20 degrees. The range of 15~20mm is degreased with acetone. YB132Cr-19Ni10Nb stainless steel flux cored wire, the wire is made of carbon steel steel, the chemical composition of the middle core is matched with the material to be welded, and the chemical composition of the weld metal is very uniform through the droplet transfer. The chemical composition and mechanical properties of the flux-cored wire are as follows: NSA4-300 silicon rectifier argon arc welder. A simple tungsten argon arc welding machine can also be used. The AX-320 type DC welding machine is equipped with a gas-electric combined self-cooling welding torch. The argon gas is controlled by the rotor flow meter and converted into a simple argon arc welding equipment. Conditional units can purchase off-the-shelf argon arc welding equipment. YB132Cr19Ni10Nb stainless steel flux cored wire is welded with 1Cr18Ni9Ti austenitic stainless steel pipe, which breaks the traditional internal argon protection welding method of pipe, improves work efficiency, saves cost, and brings great convenience to construction. From our use in engineering, it is a reliable, simple and feasible new welding process, especially for the installation unit. Two blocking plates are placed on both sides of the pipe in advance, and the rope (or wire) is fastened. After the welding is completed, the two blocking plates are taken out from the pipe. 89mm pipe, in order to save argon, local argon charging method can be used. Specifically, before welding, the blocking plate is added to the vicinity of the welding port in advance to form an isolated inflatable chamber (generally placed at 100~150mm from the welding joint), one end is inflated to the plenum, and from another A small hole in the center of the plate is out. In order to reduce the loss of argon in the tube from the intermittent mouth and reduce the protective effect, the tape can be attached along the gap of the weld before welding, and the tape is removed by welding while welding. In order to supplement the argon gas leaking from the gas chamber, the whole process of welding should be filled with argon into the gas chamber without interruption, and the flow rate of argon gas should be appropriate. The flow rate is too small, the gas protection is not good, and the back side of the weld is easily oxidized. If the flow rate is too large, eddy currents will be brought into the air during welding, and the protection effect will be deteriorated. At the same time, defects such as concaves in the root of the weld will be caused, which will affect the welding quality. Generally, the flow rate of argon-filled gas is controlled at 6~8L/min. In addition, special attention should be paid to the fact that the air in the plenum or the tube should be drained after inflation, otherwise the welding can be carried out, otherwise the welding quality will be affected. A hole with a diameter of 3~5mm is mainly used to prevent arcing during the arcing, which is caused by excessive pressure of the argon gas in the pipe, which causes the joint to be arc-retained. The other end of the pipe is filled with argon gas. (Generally 200~300mm from both sides of the weld), the soluble paper can be dissolved by the water pressure test.