Steel plate 30ххга, Dnepropetrovsk region.

STEEL 30ХХСА: FIELD OF APPLICATION AND CHARACTERISTICS
Details are made from this steel, in particular, we are talking about shafts, axles, gears, flanges, casings, vanes of compressor machines that work at temperatures up to 200 °C, levers, pushers, vertical welded structures that work at alternating loads, fasteners that work at low temperatures.(//tractor-service.com)
30KHHSA steel is not prone to flocculation, but is prone to yield brittleness. Due to the presence of chromium in the composition, the steel of this marking is very strong and resistant to corrosion. Thanks to manganese, resistance to shock loads increases, and silicon increases shock viscosity. Steel has limited weldability, so it is best to weld the metal by such methods as RDS, ADS under flux and gas protection, ArDS, ESHS. They also recommend heating and subsequent heat treatment.

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