SU1362598A1 - Flux for electric arc gas-shielded welding of stainless steels - Google Patents

Abstract

The invention relates to welding, in particular to fluxes for electric arc welding with non-consumable electrode in inert gas of stainless steels. The aim of the invention is to increase the penetration depth during welding of steel X18H10T due to the introduction of a flux containing, in wt.%, Sodium fluoride 27.5-50, chromium oxide 5-15, vanadium oxide 3-10, lithium fluoride 10-27, 5 and titanium dioxide 15-25, nickel oxide 2-20. As vanadium oxide, the flux may contain vanadium oxide and vanadium dioxide. The flux before welding is applied to each welded edge. Fusible or volatile binders are used for bonding with metal and between themselves. 2 tab. § (L SAE about: to eat (00

Description

113

The invention relates to welding, in particular to fluxes for electric arc welding with non-consumable electrode in an inert gas medium, mainly stainless steels. The purpose of the flux is to increase the depth of penetration in single-pass welding without additional feeding of the filler material.

The aim of the invention is to increase the depth of penetration of metal during single-pass welding of steel of type X18H10T without additional feeding of filler material.

As vanadium oxide, the flux contains oxide () or dioxide (VO) of vanadium.

The proposed flux is applied before welding to each edge to be welded with a width of 2-10 mm and a thickness of 0.1-0.3 mm. Low-melting binders, such as paraffin and stearin, or volatile substances, such as alcohol, are used to bond the particles to the metal and to each other.

Sodium fluoride and lithium fluoride increase the anodic voltage drop, in addition, lithium fluoride improves the formation of the weld, increasing the lithium fluoride content, and reduces the depth of penetration.

The introduction of oxides consisting of titanium dioxide, chromium oxide, vanadium oxide and nickel oxide into the composition of the flux provides for the compression of the anode arc spot by limiting the width of penetration by a liquid film of flux. At the same time, titanium dioxide and vanadium oxide improve the formation of the weld and increase the penetration depth, while chromium oxide and nickel oxide contribute to a significant increase in the depth of penetration and reduce the width of the weld, in addition, the combination of titanium dioxide, vanadium oxide and nickel oxide in this flux provides the maximum the depth

melting when welding speed is increased.

The flux was tested when welding a non-floating PCN electrode with a protective argon atmosphere of butt butt joints of pipes made of stainless steel Х18Н10Т j 108 6 and ф89-5, assembled without clearance and cutting.

The action of the proposed flux was tested on fixed joints of pipes of each size with a constant positive result.

In tab. Table 1 lists the compositions of the tested fluxes, the results of the evaluation of the quality of the external formation, the separation of slag after welding, and the penetration depth compared to welding without flux.

The quality of the yarut formation was evaluated by external inspection, the penetration depth was metallographically measured by macrosections (3 pieces from one joint) slag separation and the presence of slag visually, by the time spent on cleaning the welds from slag and the means used for stripping (hair on a metal brush or rags, etc.).

It was found that, under laboratory conditions, the time spent on stripping one joint with a diameter of 89 and 108 mm using the proposed composition of the flux is 1.2 and 1.5 minutes, respectively. The flux was applied to the edges to be welded in the form of a creamy suspension with help.

with a soft brush with a width of 5-10 mm, thickness 0.1-0.3 mm. Technical alcohol was used as a solvent.

In the experimental studies on the depth of penetration of the metal and the slag capacity after welding, depending on the quantitative ratio of the ingredients, fluxes of a number of compositions listed in Table 2 were used. one.

0

five

0

five

0

five

I

Small amount

slag is easily removed from the surface

Table 1

Nickel oxide in the following ratio, wt.%:

5 1362598в

Lithium fluoride 10-27,5 Oxide Chromium 5-15

Fluoride sodium 27,5-50 Oksidvanadi 3-10

Dioxide of titanium 15-25 Oxide of nickel 2-20

Claims (2)

Claim 50 Flux for electric arc welding of stainless steels in shielding gases, containing lithium fluoride, sodium fluoride, titanium dioxide, chromium oxide, vanadium oxide, characterized in that 55, in order to increase the penetration depth when welding стали18ΗΪ0Τ steel, the flux additionally contains nickel oxide in the following ratio of components, wt.%: β Lithium Fluoride Sodium Fluoride Titanium Dioxide 10-27.5 27.5-50 15-25 Chromium oxide Vanadium oxide Nickel oxide 5-15 3-10 2-20