Introduction to the key points of welding Hastelloy pipe
Key Points to Consider When Welding Hastelloy Pipes 1. Welding Procedure for Hastelloy Pipes During the welding process, it's important to remove any white tape that may be attached to the bottom or sides of the groove. If not removed, it should be cleaned thoroughly with acetone before proceeding with the weld. This ensures a clean and proper fusion of the materials. 2. Use low heat input during welding. The tip of the welding wire, which gets heated during the process, must always be protected by a shielding gas. Throughout the entire welding operation, short arc welding is recommended to maintain better temperature control between passes. When the arc is turned off, the crater should be filled completely, and the shielding gas should continue for at least 30 seconds after the arc is extinguished. This helps prevent hot cracking in the weld area. 3. Avoid contact between the tungsten electrode and the molten pool or the welding wire. Keep the arc length as short as possible to prevent tungsten inclusions in the weld, which can weaken the joint and cause defects. 4. Maintain an appropriate welding speed. A slower speed increases the energy input, leading to excessive burning of alloy elements and potential overheating of the heat-affected zone. This can result in larger grain structures and reduced mechanical properties. On the other hand, welding too fast may lead to poor fusion, incomplete penetration, and the formation of crater cracks due to inadequate protection of the molten pool and improper metallurgical reactions. 2. Welding supervisors and operators should wear specialized gloves and protective equipment. When filling the crater, care must be taken to avoid cracks forming in this area. A wind shield should be used at the welding site, and the gap between the two shields should be between 1 to 2 mm. For the highest standards, the gap should be within 0 to 1.6 mm. The weld surface must be free from cracks, lack of fusion, undercutting, porosity, and slag inclusions. It should also be visible on X-ray inspection for full penetration and proper fillet welds. 3. Quality Requirements for Welding: All field welds must pass radiographic testing, and both the first-pass rate and the surface quality of the welds must meet the required standards. This ensures the integrity and reliability of the welded joints, especially in critical applications where failure could lead to serious consequences. Pizza box,Pizza Box Packaging,Pizza Box Customization,Shipping Box Bulk Yutian Jifu Paper Products Co., Ltd. , https://www.yutianjifu.com