Question

Research question: How is ceiling welding possible? (It welds in the overhead (overhead) position, how can the droplets that dissolve from the electrode tip not be lowered downward by gravity but transferred to the welding bath upward?)

Answer 1

Ceiling welding is nothing but overhead welding.

Overhead welding is the most difficult position in welding.

Overhead welding is performed from the underside of a joint.

In overhead welding, the metal deposited tends to drop or sag on the plate, causing the bead to have a high crown.

To overcome this difficulty, the molten puddle should be kept small, and enough filler metal should be added to obtain good fusion with some reinforcement at the bead. If the puddle becomes too large, the flame should be removed for an instant to permit the weld metal to freeze.

When welding light sheets, the puddle size can be controlled by applying the heat equally to the base metal and filler rod.

PRVENTION OF MOLTEN METAL DROPPAGE DUE TO GRAVITY.

To retain complete control of the molten puddle, use a very short arc and reduce the amperage as recommended. As in the vertical position of welding, gravity causes the molten metal to drop or sag from the plate. When too long an arc is held, the transfer of metal from the electrode to the base metal becomes increasingly difficult, and the chances of large globules of molten metal dropping from the electrode increase. When you routinely shorten and lengthen the arc, the dropping of molten metal can be prevented; however, you will defeat your purpose should you carry too large a pool of molten metal in the weld.

One of the problems encountered in overhead welding is the weight of the cable. To reduce arm and wrist fatigue, drape the cable over your shoulder when welding in the standing position. When sitting, place thecable over your knee. With experience, cable placement will become second nature.

Becauseof the possibility of falling molten metal, use a protective garment that has a tight fitting collar that buttons or zips up to the neck. Roll down your sleeves and wear a cap and appropriate shoes.