The first method: common automotive sheet metal method
This method is aimed at the flatness of the depression. It can be known from careful observation that when using the electric welder to weld the stretching point, it is necessary to start from the periphery of the depression instead of starting from the center, and it is better to use a slow force method. Instead of using a sheet metal hammer. 
The second method: using cutting and welding
This method is large for the depression and difficult to correct in the above manner. First of all, the sag should be cut down (because the fire treatment is carried out before the operation, due to the presence of oil and gas mixed gas inside the fuel tank, it is very easy to cause explosion and dangerous situation), then the cut part of the sheet metal is shaped, and finally the corrected debris is welded. Go back to the original place and finally polish the paint.
A disadvantage of this method is that the position of the solder joint will gradually rust and affect the use.
The third method: can be repaired by frost heave
This method is for the large recess, that is, the oil in the fuel tank is first drained, and the fuel tank is removed from the frame. Rinse the inside and outside of the tank with water, then close the tank switch and fill the tank with clean water. And tighten the lid and put the tank filled with clean water into the freezer (the pool in the cold storage, cold storage and popsicles, sorbet), and pay attention to the recessed area to expose the frozen liquid surface.
The freezing time can be as long or as short as possible, usually in two or three hours, the depression can be restored. After the oil tank is restored to its original state, remove the fuel tank from the freezer and flush it with water until the ice inside the tank is completely dissolved. Finally, the water in the tank is drained, and the recess is restored where there is paint stripping. It can be painted according to the original color of the fuel tank. After the paint is dry, it can be used for loading.
The fourth method: the subtle operation of the crowbar
This method is used when the tank has a small recessed area. This method is more suitable for patience and eyes. It is suitable for the paint to be undamaged. Especially for the fuel tank that has been painted, firstly prepare crowbars and rubber head hammers with various bending angles. The crowbar head also needs to be fitted with a rubber head, and secondly it needs a lamp with strip light, and finally enough patience and time.
The fifth method: can be repaired by stretching
This method is used when the oil tank has a small recessed area, that is, the gasoline in the fuel tank is first drained, the fuel tank is removed from the frame, and a suitable iron strip is found, and one end of the iron strip is soldered with tin. In the depression of the fuel tank, the other end of the iron bar is clamped on the vise, and the fuel tank is hugged with both hands and pulled outwards. After repeated several times, the recessed portion can be restored to its original state. Then use a soldering iron to iron the iron strip, wipe the recess to restore the location, and finally paint according to the color of the tank at the recovery of the recess. After the paint is dry, it can be used for loading.
Sixth method: suction cup suction method
This method is arguably the safest and most effective, and it works well for the size of the recessed area. The suction cup suction method requires the following tools:
Middle Heavy Duty Casters With PP Wheels
Casters And Wheels,2 Inch Heavy Duty Casters,E27Heavy Duty Industrial Casters,Heavy Duty Casters With Brakes
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