HUGONG POWERTIG 300DPIII, Руководство пользователя

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1.6.6. Finish the bead
As the coating on the outside of the electrode burns off, it forms an envelope of protective gases around
the weld. This prevents air from reaching the molten metal and creating an undesirable chemical
reaction. The burning coating, however, forms slag. The slag formation appears as an accumulation of
dirty metal scale on the finished weld. Slag should be removed by using a chipping hammer.
PEENING THE SLAG FROM A WELD JOINT CUASES SMALL CHIPS OF METAL TO FLY
THROUGH THE AIR! Metallic chips flying through the air can cause eye injury or injury to other
parts of the head, hands or exposed portions of the body. Wear goggles or safety glasses with
side shields and protect the hands and other exposed parts of the body with protective garments,
or if possible, work with a shield between the body and the work piece.
The intense heat produced at the arc sets up strains in the metal joined by welding. Peening the weld not
only removes the scale left behind in the welding but relieves the internal strains developed by the
heating and cooling process.
2. TIG welding skill
Gas Tungsten Arc Welding (GTAW) or TIG (Tungsten Inert Gas) as it is commonly referred to, is a
welding process in which fusion is produced by an electric arc that is established between a single
tungsten (non-consumable) electrode and the work piece. Shielding is obtained from a welding grade
shielding gas or welding grade shielding gas mixture which is generally Argon based. A filler metal may
also be added manually in some circumstances depending on the welding application.