Welding in Space

For the first time the thought of having to perform work on welding and cutting in space SPKorolyov expressed in the 1965 Major differences from terrestrial space environment - especially in the high vacuum of virtually unlimited rate of diffusion of gases from the weld zone, a wide range of temperatures at which can be be welded products, weightlessness. In addition, welding quality affects a number of secondary factors - the limited mobility of the astronaut in a spacesuit-operator, increased security requirements, and other works of the first experiments on welding in space, held October 16, 1969 aboard the "Soyuz-6" GS Shonin and V. Kubasov with the installation "Volcano." Installation allows you to automatically perform an arc, plasma and electron beam welding.

When arc welding in space to the greatest degree of change of the electrode metal transfer process. The drop grows to larger sizes that are on the ground can not be obtained, several times larger than the diameter of the electrode, the electrode is held at the end of a long time - about 3 seconds. Increasing the size of the drop reduces the current density decreases the stability of the arc. Slightly improves the process of applying to the arc current pulses. Mechanical properties of weld high enough, no more defects than in terrestrial conditions.

The best results were obtained with an electron-beam welding. Power electron beam gun was carried out from the battery. Constant voltage was converted to AC through inverters, and then increased with a transformer and rectified. In the gun instead of the magnetic focusing electrostatic applied, which simplified the design and reduced weight of the installation.

In the period from 1979 to 1984 in space experiments were conducted on thin-film deposition of metallic coatings on samples of structural steels by thermal evaporation and condensation. The experiments were conducted at facilities such as "evaporator", equipped with two electron beam guns.

There were obtained about 100 specimens, in some cases with unique properties.

July 14, 1984, and astronauts S.Savitskoy V.Dzhanibekovym were first carried out experiments on electron-beam welding with a spacewalk. They used a welder URI (universal hand tool).

He was allowed to carry out welding, cutting, brazing, heating the metal coating. All these operations were carried out short-electron-beam gun, which the astronaut in his hand. The mass of the entire apparatus of about 30 kg, and the electron beam gun - 2.5 kg. Power consumption - 750W.

Welded samples of steel and titanium. The quality of connections is sufficiently high. In connection with weightlessness for cutting the molten metal is removed from a bad cut.

When heated, it is difficult even approximately to control the temperature of the metal, as in the open space on the metal are formed discoloration.

Experiments were performed on 20 different samples. They have shown high reliability and availability of welding in space. Currently, a new apparatus for welding in space, "Universal."

Welding technology:

manual arc welding semi-automatic welding argon arc welding machine welding electroslag welding plasma welding laser welding electron beam welding

gas welding resistance welding spot welding seam welding projection welding butt welding welding underwater welding in space