2Pass welds and low back-beads Hello. Today we’ll be welding stainless steel pipes again. As I mentioned in the previous video, I’ve captured the 2Pass welds and the low back-beads. I’d appreciate it if you could press “Subscribe” and “Like.” This is a 65A (2 1/2 inch) SCH10 stainless steel pipe. In the previous time, a pipe of the same size was used for 3Pass welding. This video shows how to weld a pipe the same size as before to 2Pass and lower the back-bead height. And in the previous video, I showed you welding using a large nozzle. Today I’m going to show you how to weld using a small nozzle. I’ve told you in another video that it’s easier to control the melting pool by using a small nozzle. So today I’m going to show you how to weld using a small nozzle, not a large nozzle. The nozzle has an internal diameter of 12mm. It’s a big eight. Tungsten length is about 6mm. I’ll set it up and weld it. The “weaving” method is the same as before. The nozzle will move one step at a time, as if it were walking over the upper edge of the groove. And in this video, we’re going to remove all the tapes and weld them together. The “tack-weld” condition of the pipe is the same as before. The gap is the same. “Tack-welded” in four places. The usage of argon gas is the same as before. Argon gas usage is about 18 to 20. The use of “purge” gas is between 13 and 15. So the “tack-weld” condition of the pipe is identical to all the previous videos. This clip is designed to compare the welding method of the previous video. So if you haven’t seen the previous video, please watch the previous video and compare it to this one. In the previous image, we used a thin weld bar to weld it to 3Pass. This video shows how to weld with 2Pass and make a low back bead. The current used 70 amps. Welding rods used 2.4 mm. When making low back-beads, the supply of weld rods should not be high. It is recommended to supply only enough weld rods to prevent them from being separated from the melting pool. And instead of feeling that the molten welding rod is being sent to the rear of the pipe, spread the melting pool on both sides so that the back-bead of the pipe is low. Then a low-height back-bead is created. And if you use a little higher current to make a larger melting pool, it’s easier to weld this way. The advantage of this welding method is that it uses a slightly higher current compared to the size of the pipe and the melting pool is large, making it easier to connect the weld at the “track-weld” and the finish. Back-bead welding is complete. I’ll show you the inside of the pipe. Be careful when the pipe is hot. If you look outside the pipe, it’s this much grooved. If you look at the inside of the pipe, you’ll see a back-bead that’s this low. As you know, stainless steel pipes have a lot of thermal deformation. So after the final weld, the back-bead will be slightly higher. Compare the height. Final weld (CAP PASS). The current used 70 amps. And the welding rod used 2.4 millimeters. In the previous video, we used 80 amps. The current felt a little high. So I tried to turn the current down a little bit and use 70 amps. As you can see, the amount of heat we’re able to control is more than the welding in the previous. But I think the welding speed is a little slower than the previous video because I’m trying to penetrate the low current. So we’ve done a final weld with two currents. Compare the two things and take a look at them. Please try it yourself and make your choice. When I was welding, I felt that the nozzle was not smooth, but the bottom of the nozzle was broken. Can you see that? The bottom of the nozzle is broken. Maybe that’s why the welding wasn’t smooth. The part where the nozzle was rather frivolous and crisp… Please excuse me. So… in the previous video and in this video, we’ve welded pipes of the same size in two different welds. Compare these two welding methods. And the size of the nozzle was different from the previous video. So please compare this and see. As I always say, there are many different welding methods in the same situation. There are many different welding methods besides this way. I’ll show you those things one by one in the next Hold the crater at the end. So here’s how the welding is done. No “purge” is required for final welding. But if you do that, it’ll darken the inside of the pipe. So I did “purge” to make it easier to compare back-beads. Be careful when the pipe is hot. Safety is the best. I tried to be funny. Slapstick! You know that, right? I’ll show you the inside of the pipe. This is the result. The back-bead is a little higher than the first one. So next is the outside of the pipe. It looks like this. A subscriber said he was curious about the inside of the pipe. Look at it a lot. So I’m going to wrap up today’s video like this. My welding method is not necessarily the answer. But it’s one of the welding methods that we can apply in a variety of situations, so I hope it will help. I hope this video will help all welders grow motivated and help a little bit. Press “like” please. I hope you’ll “share” it with a lot of people. If you “subscribe” and come to my channel, there are more different weld videos. Thanks for watching.