Claims:The scope of the invention is defined by the following claims:

Claim:
1. A shielding gas provision box for welding/WAAM of material with high affinity towards atmospheric constituents, comprises of:

a) A stainless steel provision box (8) with holes at the bottom center on each side to provide inlet for shielding gas. (4 and 7).
b) Shielding gas enters the box (8) passes through a copper wire mesh (3) followed by filter sheets (5).
c) A contained chamber (1) comprising mineral wool (9) is placed in between the filter sheets (5)
d) Specimen to be welded is placed over a base (6) located next to the filter sheets (5).

2. According to Claim 1, velocity of the shielding gas is controlled by copper wire mesh, filter sheets and mineral wool.

3. As mentioned in claim 1, shielding gas forms a shielding atmosphere over the object to be welded.

4. According to claim 1, shielding gas prevents oxidation on work piece during welding. , Description:Field of Invention
The present invention relates to field of welding and WAAM (wire arc additive manufacturing) processes for highly reactive materials where oxidation has to be nullified. The invention incorporates the use of box to deliver effective shielding atmosphere to the materials that are being joined/bridged.
The objectives of this invention
There are three prime objectives that are aimed to be achieved through this invention are i) To provide an apparatus to supply inert gas at the face and root sections of the weld, to prevent interaction between atmospheric constituents and material. ii) The apparatus should be handy and reliable for performing welding/WAAM processes. iii) The apparatus must be flexible enough to be used on articles of diverse welding processes.
Background of the invention
The aim of this invention is concerned with building gas shield at the weld area during the welding operation or WAAM, in order to prevent the occurrence of oxidation in the material.
In case of electrically operated arc welding processes like gas metal arc welding (GMAW), cold metal transfer (CMT), shielded metal arc welding (SMAW), submersible arc welding (SAW) and wire arc additive manufacturing (WAAM), the filler metal is transferred in the form of a consumable electrode along the arc to the area to be welded whereas non consumable electrode process such as gas tungsten arc welding (GTAW), electron beam welding (EBW) and laser beam welding (LBW) rely upon auxiliary feed systems to introduce filler material to the weld.
In all of the above-mentioned welding processes there is one main and prime predicament that has to be conquered is the oxidation of the material. It is a common understanding that if the welding takes place under an inert atmosphere, then the oxidation taking place during the weld process can be controlled. Moreover, the causes of failure due to brittleness are the absorption of hydrogen, oxygen and nitrogen by the weldment/reinforcement in welding/WAAM processes from the vicinity as a result of disruption of shielding gas flow by the plasma plum formed.
Several previous patents aimed at successfully developing and using an inert atmosphere for shielding and following different methods have been attempted. Examples of such patents include U.S. Pat. No. 3, 450, 857, U.S. Pat. No. 5, 398, 862, U.S. Pat. No. 4, 567, 343 and copious other patents have accomplished various techniques to arrive at the shielding of the atmosphere.
Summary of the invention
The aforesaid objectives have all been achieved in present invention. This invention provides an apparatus which gives an inert gas which provides shielding over the part that is being welded or added, in order to prevent oxidation.
The apparatus consists of a box with holes at the bottom center of each side to provide for inert gas inlet. The argon gas as it enters the box passes through a copper mesh material so that the velocity of the gas flow gets minimized, further it passes to the next layer through a porous sheet of metal into the layer of mineral wool which further drops the velocity of the gas, now again it is allowed to pass through a porous sheet then into the work area where it forms an shielding atmosphere over the work-piece so as to prevent oxidation on the weld. The object to be welded is kept immersed inside the gas shield so as to prevent oxidation.
Detailed description of the invention
The aforesaid objectives have all been achieved in present invention. This invention provides an apparatus which gives an inert gas which provides shielding over the part that is being welded or added, in order to prevent oxidation.
The apparatus consists of a box with holes at the bottom center of each side to provide for inert gas inlet. The argon gas as it enters the box passes through a copper mesh material so that the velocity of the gas flow gets minimized, further it passes to the next layer through a porous sheet of metal into the layer of mineral wool which further drops the velocity of the gas, now again it is allowed to pass through a porous sheet then into the work area where it forms an shielding atmosphere over the work-piece so as to prevent oxidation on the weld. The object to be welded is kept immersed inside the gas shield so as to prevent oxidation.
Brief description of Drawing
Figure 1: Schematic diagram of Compact Shielding Gas Box for Welding
Figure 2: Working of Compact Shielding Gas Box for Welding and WAAM Processes
In the figures which are illustrated exemplary embodiments of the invention.
4 Gas inlet valve for gas to enter, 3 Copper wire mesh which is used to minimize the velocity, 2 Side inlet valve, 5 filter sheets of dimensions 390 x 230 x 0.6 mm with holes of 1 mm, 9 Mineral wool which further drops the velocity, 1 height of the chamber is 10mm where mineral wool is placed, 6 base for the process to be carried out, 7 one side open chamber where shielding gas is supplied, 8 Stainless Steel 204 of thickness 5 mm plate which is welded and acts as a chamber, 10 flow of shielding gas inside the chamber.