Method for preparing bottled multi-element mixed gas

Abstract

The invention discloses a method for preparing bottled multi-element mixed gas. The method is characterized by comprising the following steps of: (A) connecting a qualified gas bottle to a port of a filling busbar; (B) vacuumizing the gas bottle and a filling pipeline system, and controlling the volume content of oxygen in the gas bottle and the filling pipeline system to be less than and equal to 3*10<-6> and the volume content of water to be less than and equal to 3*10<-6>; (C) filling argon into vacuumized gas bottle to serve as base gas, and controlling pressure in the gas bottle to be 0.1 MPa; (D) filling gas in an argon and nitrogen mixed gas container into the gas bottle in the step (C), and controlling pressure in the bottle to be 0.2 MPa; (E) filling helium into the gas container in the step (D), and controlling pressure in the bottle to be 3.3 MPa; and (F) when the wall of the bottle is cooled to room temperature, filling the argon into the gas bottle in the step (E), and controlling pressure in the bottle to be 9.9 to 10.1 MPa to obtain the helium, nitrogen and argon bottled multi-element mixed gas. The method is mainly applied to protective gas for welding core aluminum alloy parts of high-speed railways.

Description

technical field [0001] The invention relates to a method for preparing a mixed gas, in particular to a method for preparing a bottled multi-component mixed gas. Background technique [0002] Traditional welding protective gas usually uses argon or a mixture of helium and argon, but the content of impurities in argon easily exceeds the specified standard, which not only affects the protection of molten metal, but also easily produces defects such as pores and slag inclusions, making The quality of the welding joint deteriorates and increases the burning loss of the tungsten electrode of the welding torch, which cannot meet the high-quality requirements. The mixed gas of helium and argon has no corrosion on the steel cylinder, and the welding quality is better than that of argon, but the above defects still exist. Contents of the invention [0003] The object of the present invention is to provide a method for preparing bottled multi-component mixed gas, so as to overcome th...

AI Technical Summary

Problems solved by technology

[0002] Traditional welding protective gas usually uses argon or a mixture of helium and argon, but the content of impurities in argon easily exceeds the specified standard, which not only affects the protection of molten metal, but also easily produces defects such as pores and slag inclusions. The quality of the welded joint deteriorates and increases the burning loss of the tungsten electrode of the welding torch, which cannot meet the high-quality requirements. The mixed gas of helium and argon does not corrode the steel cylinder, and the welding quality is better than that of argon, but the above defects still exist