6G welding is a difficult technique, which includes almost all postures in space. Proficient in 6G welding posture, it helps the welders have comprehensive skills in manual arc welding for termite joint welding.
Materials and equipment
– Prepare the sample tube for welding, cutting and shaping according to the size given.
– Welding rods: Welding rods with diameter suitable for welding joints, are dried and preserved according to certain regulations (drying in the oven at 300ºC for 2 hours, preservation at 150ºC, during welding. Preserved in a mobile dry bulb and used within 4 hours).
+ Welding lining E 7016 Ø 2.4mm
+ Welding intermediate layers, E 7016 Ø 3.2mm coating.
– Power source: DC welding machine.
– Protective, leather, leather gloves …
– Work tools, slag hammer, iron brush, grinder, ..
1. Step 1 – Fabrication of materials
– Preparation of embryos:
Cleanliness: grinding bevel surface, blunt edge. Grinding surface of the welding pattern (from the edge 30 – 40mm).
2. Step 2 – Install the device.
DC Welding Machine, DC + Polarizer
The negative terminal (-) of the welder fits into the weld
An anode of the welding machine (+) fits into the welding rod
A convenient electrical adjustment mode for welding jobs. The soldering source must reach a current of 55 – 150A.
3. Step 3 – Welding.
Place a tube on the dashboard facing the uprange, using the slot of the gap of the welding rod with a U-shaped bending rod, placing the remaining pipe on the top, the beveled edge being joined together. Into a welding groove.
– With a maximum edge deflection of 1.6mm.
– Welding welds with a length of 10 – 15mm symmetric through the center of the tube
– Welds must have good penetration on the leg and penetrate into the 1.6mm junction.
– It is possible to move the cushion to the appropriate gap to be welded without being deflected open gap.
– Third and fourth welds are perpendicular 90 ° from welds 1 and 2.
– Grinding the welds. Requires good grinding, technical requirements, then the weld will achieve the quality of the rice.
– Place the sample tube on a “U” bar, the two beams rotate together, using the gap of the gap of welding rod diameter.
– Use a round bar of appropriate diameter from 10 to 15mm placed on the groove to weld.
It is possible to attach 4 welds to a large diameter pipe and attach 3 bolts to a small diameter pipe.
4. Weld lining:
– Welded specimens are soldered and specially treated to prepare the solder lining.
– Select welding rod E 7016 Ø 2.4mm.
– Set the current to 55 – 85mm.
– Location of the soldering pattern: Fix the fixed solder clamp at 45º above the ground with the fixings fixed at 1, 4, 7 and 10 hours clockwise (as shown).
– Start welding at 6h30 ‘in the weld, welding rod angle to the vertical axis 5º – 10º. Sold to 4h position before changing the welding rod angle.
– Arc inside the welding groove. Keep the arc burning evenly and the arc gap is equal to 2 times the welding rod diameter, with displacement, oscillation at the tip of the welding rod, serrated or semi-circular and providing sufficient heat to the dull edge. The transverse vapor moves to keep the metal and the slag from falling away, as the solder is 45º at the posture.
After 2 to 3 times as above, adjust the arc length by 0.5 times the welding rod diameter. It is possible to adjust the angle of the welding rod to a suitable one, pressing the slag toward the back of the welding direction so that the tank is neat and slag as close to the end of the welding rod as possible.
– Try to make a hole in the hole at the top of the tank a little wider than the diameter of the rod to facilitate the penetration of the metal completely and stick to both sides of the welding groove. Then stop the arc length by about 0.8mm from the sharp edge of the blunt edge and start moving gently.
– The solder angle 55º – 65º compared to the surface of the welding sample below.
– In the process of welding with large openings, it is possible to move the welding rod in reverse method. Put the welding rod on top of the welding rod diameter then back 1/2 times the welding rod diameter.
– Welding position 4h before changing the welding rod angle.
– With wide spacing the splice can be divided into several layers overlapping welding (as shown).
– Divide the fill layer into three parts (divided by the eye) and then solder the first two parts.
– Finishing the first coat, clean the weld, especially the groove must be thoroughly cleaned and must ensure enough groove to drain slag when welding.
Then split the welded surface into 3 parts and weld over 1/3 of the previous weld.
+ The welding line on the edge of the joint is approximately 1.6mm.
+ Height of reinforcement range is from 0.8 to 1.6mm.
– Finishing weld spatula, clean the weld with tools such as: chisel, grinder, brush rust.
– Note: The connecting rod must be secured.
Checking the weld by the naked eye: The welded surface needs to be uniformly high, arched, uniformly welded, straight welded, welded, straight.