Abstract: Use of a steel alloy for well pipes of perforating units for perforation of borehole casings, with the steel alloy comprised, in mass-%, of Carbon (C) 0.12-0.25, Manganese (Mn) 0.5-2.0, Silicon (Si) 0.1-0.5, Nitrogen (N) 0.006-0.015, Sulfur (S) <0.005, Chromium (Cr) 0.1-1.5, Molybdenum (Mo), <0.3, Nickel (Ni) <1.0, Vanadium (V) <0.25, Niobium (Nb) 0.010-0.15, Titanium (Ti) 0.02-0.06, Boron (B) 0.001-0.006, Calcium (Ca) <0.0025, and iron as well as impurities resulting from smelting as remainder, wherein the steel alloy is heated at a heating rate of 1-100 K/s to an austenitizing temperature between 10 to 50° C. above its transformation temperature Ac3, and held at this austenitizing temperature between 0.

Abstract: A method of using a steel alloy, the steel alloy having a composition containing in mass %, 0.09-0.13% C, 0.10-0.50% Si, 1.10-1.80% Mn, max. 0.02% P, max. 0.02% S, 1.00-2.00% Cr, 0.20-0.60% Mo, 0.02-0.06 Al, 0.10-0.25% V, the balance iron and incidental impurities, includes the steps of forming a tube from the steel alloy; air hardening the tube in the presence of inert gas, and incorporating the tube in the production of a compressed gas container. The steel composition may also be used as material for producing formed structures in light weight steel construction.