VSM 13935-1971 Cylinders and classes of cylinder valves connected by valves for die pressure ≤ 200 bar Part 3 Fitting of threaded joints for gases and gas mixtures
1971VSM 13935-1971 Cylinders and classes of cylinder valves connected by valves for die pressure ≤ 200 bar Part 3 Fitting of threaded joints for gases and gas mixtures