DE1236104B - Submerged arc welding of steel with an electroless filler wire - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

B 23 k

German class: 9 pm - 30/17

Number: 1 236 104

File number: F 40156 VIII d / 21 h

Filing date: July 4, 1963

Opened on: March 9, 1967

The invention relates to a submerged arc welding process for steel with a current-carrying, melting steel electrode and a currentless, melting filler wire.

The usual methods of submerged arc welding have disadvantages compared to the manual welding process with regard to the physical properties of the welds. One such disadvantage is the high oxygen content of the weld metal, which is almost six times that of the manual welding process and leads to impairment of the impact resistance, ie the ductility of the weld. This disadvantage is due to the inadequate deoxidizing effect of a premelted, grained welding powder, which contains MnO, SiO ₂ , CaO, Al ₂ O ₃ and MgO as the main constituents and is not able to produce an adequate deoxidizing effect during the welding process. Second, a disadvantage is the increase in the silicon content as a result of the extremely high increase in non-metallic inclusions, such as silicates, in the weld metal, which impairs the ductility of the weld. Thirdly, attention is drawn to the high energy density of the electric current, which causes the weld bead to heat up strongly, which delays the cooling of the weld and results in the formation of such a metallographic structure, which has coarse and brittle crystals and is referred to as a dendritic structure. It also significantly reduces the ductility of the weld.

It is already known that with submerged arc welding, the energy density in the weld pool increases the supply of a massive so-called cold, d. H. non-live wire to diminish and this wire also for the metallurgical influence of the weld metal, z. B. by an improved To use the deoxidation effect of the manganese introduced in the additional wire. Even the use of a tubular electrode with a welding agent filling (selenium wire), the one Enabling an even greater supply of additives is no longer new in submerged arc welding. However, it has not yet succeeded in addressing the above-mentioned disadvantages of submerged arc welding remove.

This object is achieved by the method according to the invention in that a selenium wire is used as the additional wire will. .

It can be useful to connect the additional wire either with the same or with a different one Submerged arc welding of steel with an electroless filler wire

Applicant:

FUJI WELDING ELECTRODE CO., LTD.,

Tokyo

Representative:

Dipl.-Phys. H. Schroeter, patent attorney,

Munich 25, Lipowskystr. 10

Named as inventor:
Izumi Morimoto,
Hiroshi Nakayama, Tokyo

Claimed priority:

Japan July 5, 1962 (27,661)

Speed like advancing the electrode wire.

An advantageous selenium wire for carrying out the method according to the invention is characterized in that that its outer, tubular steel shell as a deoxidizer 0 to 5% manganese, 0 to Contains 5% silicon and 0 to 3% aluminum, and that the core consists of deoxidizing agents, Denitrants, alloying elements, slag-forming substances and arc stabilizers composed.

According to the same principle on which the present invention is based, a vertical Welding processes for two opposing steel plates are used, with cooling Copper shoes are used, which are permanently attached to an opening provided between the steel plates Can be moved along from bottom to top to make a satisfactory weld, either with or without using granular welding material to shield the arc.

The invention is further described with reference to the drawings, in which

F i g. 1 is a generally schematic side view of the apparatus for performing the inventive method Procedure is

F i g. 2, (a), (b) and (c) each represent an enlarged cross-sectional view of preferred additional wires according to the invention with welding agent filling,

F i g. 3 shows a schematic side view of an apparatus for carrying out an embodiment of the invention and

709 518/408

F i g. 4 shows a schematic side view of an apparatus for carrying out another embodiment of the invention.

The device shown in Figs. 1, 3 and 4 comprises a motor 7 for the advance of an electrode wire 1 with an electrode mouthpiece 2 and a motor 1, la for the advance of a tubular, weld-filled additional steel wire 5, which is guided by means of guide rollers 6, 6 a and melts as a result of an arc generated between the electrode wire 1 and a base material 4. The arc is shielded by a granular welding means 3, which at the same time serves as a protective cover over the molten metal bath (not shown). The arrow A indicates the direction in which a welding process is taking place. In the case of the in FIG. 3, the electrode wire and the additional wire are arranged on a common shaft and therefore perform a mechanically synchronized movement by means of a motor 7, while the additional wire in the device shown in FIG. 4 is advanced at a freely selected speed by means of a motor 7 α , which runs independently of the motor 7, so that in the latter case a non-synchronized relationship between the electrode wire and the additional wire is established.

The in the F i g. 2, (α) to (c) shown tubular, welding material-filled additional wire (selenium wire) comprises an outer shell 9 made of thin strip steel in the form of a tube and an inner filling, which consists of a welding powder 10 alone and / or a welding powder together with a metallic one Substance, preferably in the form of a rod 8, composed within the welding powder is arranged. As shown in Fig. 2, (c), the sleeve 9 can have an inwardly bent seam, which is sealed by a metallic material 11 in order to prevent the welding powder from falling out impede. In either case, no current is passed into the filler wire.

The following examples illustrate particular embodiments of this invention, wherein under "Ratio of the application speed" in the tables the ratio of the feed speed of the additional wire or selenium wire to which the steel electrode is to be understood.

example 1

The welding of mild steel was carried out using a filler wire according to the invention carried out, which contained manganese iron and fluorspar in its interior; the results are in the Table 1 shown.

Example 2

The welding of steel with high tensile strength in the range of 60 kg / mm ² was carried out using a filler wire according to the invention which contained in its interior nickel, molybdenum, manganese iron and fluorspar (see Table 2).

Example 3

The welding of steel with high tensile strength in the range of 70 kg / mm ² was carried out using an additional wire containing nickel, chromium, molybdenum, manganese iron and fluorspar in its interior (see Table 3).

Example 4

Welding steel with high tensile strength

in the range of 80 kg / mm ² was used

carried out an additional wire according to the invention,

which contained nickel, chromium, molybdenum, manganese iron and fluorspar in its interior (see Table 4).

Example 5

ίο build-up welding were according to the invention under Use of an additional wire according to the invention carried out, which in its interior nickel, chromium, Vanadium, molybdenum, chromium carbide, manganese iron and fluorspar (see Table 5).

According to the present invention, it is also possible to weld an electric rod wire made from mild steel to be used while feeding a tubular filler wire inside it has a welding agent filling that contains specific alloying elements, or an electrode wire to use, which contains specific components, while a filler wire with a welding agent filling that contains specific alloying elements to one for base materials of any kind including alloy steel such as stainless steel, tungsten steel, chromium-molybdenum steel and to get cast iron matching weld. The filler wire can be of the same type as the base material be.

According to the welding method of the invention, the deoxidation is therefore carried out completely, because the deoxidizer is in the non-oxidized state when it is supplied.

In contrast to the prior art, in which a special electrode wire was used, which contained a considerable amount of deoxidizing agent in its interior to make up for the inadequate To compensate for the deoxidizing effect, in the method according to the present invention, at which a welding agent-filled additional steel wire is used, an electrode wire made of ordinary Steel can be used with satisfactory results.

Furthermore, in addition to the deoxidizing agent, an appropriate amount of an alloying element such as nickel, chromium, molybdenum and vanadium can be added to the filling of a filler wire according to the invention in order to influence the chemical composition of the weld to be obtained in the desired manner. Thus, as illustrated in the above examples, welding of various types of steel with high tensile strength in the ranges of e.g. B. 60, 70, 80 and 100 kg / mm ² and other types of steel that are needed at lower temperatures can easily be carried out. In addition, build-up welds with the required hardness can be obtained. These goals have not been achieved by prior art methods.

Furthermore, according to the invention, the inner filling of the additional wire can be of various types Welding means include so that the silicate concentration in the molten slag pool of the weld is decreased. It follows that the amount of reduced silicon and non-metallic inclusions, which gets into the weld is reduced and the ductility of the weld is therefore considerable is improved.

Furthermore, since no current is supplied to it, the filler wire according to the invention melts only due to the reason the heat of the arc, which arises from the contact of the electrode wire with the base material, which helps to reduce the density of the electric current.

As a result, the formation of dendritic structures, which impair the ductility of the

Welding would bring with it, the welding voltage is reduced, the zone in which the arc attacks, becomes less brittle or weakened, the breaking strength is significantly improved, and the welding efficiency is greatly increased because of the application of the metallic components of the filler wire according to the invention.

Chemical composition
of the weld in ° / o Table 1 structure Impact resistance
in kg / cm ²
at 0 ° C Ratio of
Application
speed procedure 0.05 C 0.12 Si
0.63 Mn 0.015 P
0.014 S 0.20 Cu
0.07 C 0.51 Si
1.21Mn 0.02OP
0.022 S 0.18 Cu Crystal grains finer; education
dendritic crystals
insignificant
Crystal grains coarser; education
dendritic crystals
considerable 20.2
6.0 1.3 to 2.0
1.0 According to the invention
Known

Table 2

procedure Chemical composition
of the weld in ° / o structure Impact resistance
in kg / cm ²
at 0 ⁰ C Ratio of
Application
speed According to the invention 0.04 C 0.26 Si Crystal grains finer; education 0.98 Mn 0.016 P dendritic crystals 0.012 S 1.12 Ni insignificant 11.0 1.3 to 2.0 0.36 mo Known 0.06 C 0.25 Si Crystal grains coarser; education 1.01 Mn 0.024 P. dendritic crystals 0.025Si 0.034Ni considerable 5.8 1.0 0.040 mo

Table 3

procedure Chemical composition
of the weld in ° / o structure Impact resistance
in kg / cm ²
at 0 ° C Ratio of
Application
speed According to the invention 0.06 C 0.24 Si Crystal grains finer 1.22 Mn 0.018 P 0.012 S 0.23 Cr 11.8 1.3 to 2.0, 1.68 Ni 0.45 Mo Known 0.06 C 0.32 Si Crystal grains coarser 1.28 Mn 0.018 P 0.020 S 0.18 Cr 6.4 1.0 1.62 Ni 0.44 Mo

Table 4

procedure Chemical composition
of the weld in ° / o structure Impact resistance
in kg / cm ²
at 0 ° C Ratio of
Application
speed According to the invention 0.06 C 0.23 Si Crystal grains finer 1.45 Mn 0.018 P 0.014 S 0.52 Cr 12.4 1.3 to 2.0 1.80 Ni 0.54 Mo Known 0.06 C 0.43 Si Crystal grains coarser 1.90 Mn 0.017 P 0.015 S 0.57 Cr 5.8 1.0 2.60 Ni 0.55 Mo

Tabel

C. 0.10 Chemical composition of the weld (in ° / o) Si 1.20 0.85 Mn 1.20 Cr j Mon 0.30 Vickers hardness of the
Welding until 0.10 until 1.30 0.90 until 1.30 0.40 to 0.60 0.50 kg / mm ² 0.06 until 0.40 0.80 until 0.60 2.80 until 3.20 0.60 to 0.90 0.30 225 to 275 0.06 until 0.75 0.80 until 1.00 0.60 until 1.00 5.00 to 6.00 325 to 375 0.03 until 3.00 0.30 until 1.00 0.80 until 1.20 2.00 to 3.00 480 to 560 0.60 until 0.80 until until W + Co 650 to 740 2.50 0.60 0.10 to below 740 0.30 to 0.10 to 50.0 to 55.0

Claims (12)

Patent claims: 1. Submerged arc welding process for steel with a current-carrying, consumable ¹ S steel electrode and a currentless, consumable filler wire, characterized in that a selenium wire (5) is used as filler wire (5). 2. The method according to claim 1, characterized in that the tubular «additional steel wire (5) continuously at a freely selected speed, regardless of the speed the electrode wire feed, is advanced (Fig. 4). 3. The method according to claim 1, characterized in that the tubular additional steel wire (5) continuously advanced at the same speed as the electrode wire (1) (Fig. 3). 4. selenium wire for carrying out the method according to claim 1, characterized in that its outer, tubular steel shell (9) as a deoxidizer 0 to 5% manganese, 0 to 5% Contains silicon and 0 to 3% aluminum, and that the core (10) consists of deoxidizing agents, Denitrants, alloying elements, slag-forming substances and arc stabilizers composed. 5. selenium wire according to claim 4, characterized in that the welding agent filling (10) of the core at least one deoxidizer from the calcium, magnesium and zirconium group in admixture with manganese and silicon or manganese, silicon and titanium. 6. selenium wire according to claim 4 or 5, characterized in that the core is additionally to the welding means (10) contains a metallic substance (8 or 11) of the same or of a different type, such as the outer steel shell (9). 7. selenium wire according to claim 4 to 6 for welding mild steel, characterized by the following components (in percent by weight): Fluorspar 20 to 90 Manganese iron 5 to 50 Titan 5 to 20 Wollastonite 20 to 95 8. selenium wire according to claim 4 to 6 for welding types of steel with high tensile strength, characterized by the following components (in percent by weight): Fluorspar 10 to 70 Manganese iron 5 to 40 Titan 0 to 30 Wollastonite 10 to 70 Nickel 5 to 60 Molybdenum 5 to 20 9. selenium wire according to claim 4 to 6 for welding types of steel with extraordinary high tensile strength, characterized by the following components (in percent by weight): Fluorspar 10 to 70 Manganese iron 5 to 40 Titan 0 to 30 Wollastonite 10 to 70 Nickel 5 to 70 Molybdenum 5 to 30 Chromium 5 to 60 10. Selenium wire according to claim 4 to 6 for build-up welding, characterized by fol constituents (in percent by weight): Fluorspar 0 to 30 Manganese iron 5 to 80 Titan 0 to 20 Wollastonite Obis 30 Nickel 20 to 100 Molybdenum 5 to 80 Chromium 5 to 80 Chromium carbide 5 to 50 Tungsten carbide 50 to 100 11. Application of the arc welding process according to claims 1 to 10 to welding a seam between cooling copper shoes in a vertical direction from bottom to top. 12. Modification of the method according to claim 11, characterized in that the Welding without the use of a welding . powder to shield the arc will. Documents considered: German Auslegeschrift No. 1 012 712; U.S. Patent Nos. 2,709,213, 2,909,642, 931,886, 3,024,352. 1 sheet of drawings 709 518/408 2.67 © Bundesdruckerei Berlin