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GPR-300 H

Unitor GPR-300 H is a high recovery electrode of rutile type for welding in the flat and horizontal-vertical position. It is specially suitable for horizontal-vertical and horizontal fillet welding.

GPR-300 H has a recovery value of approx. 180%, the coating containing approx. 60% iron powder. During welding, the electrode should be pulled along the groove allowing the coating to be in contact with the base material. Preferably use DCpolarity. The electrode can be used at a welding speed of up to 50 cm/min. when A-measurement (throath thickness) is 3.5 to 6 mm. When horizontal/vertical fillet welding on heavier material, a large electrode diameter e.g. 5 mm. in relation to A-measurement can be used.

The electrode is suitable for welding materials which have zinc and iron oxide rust protective primer coatings. However, observe all necessary safety precautions concerning the fumes from the primer. Consult the chapter on welding fumes.

3.01

The A measurement should be 7/10 of material thickness.

GPR-300 H is a typical electrode where large sections of steel are to be replaced but it is also useful for general repair work. The high welding speed, good welding properties, and high deposition rate reduce the risk of heat deformation and stress. Welding with this electrode ensures low spatter. The bead has a smooth surface and the slag is self-releasing. This electrode is recommended for welding flanges to tubes in the horizontal position.

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