SU1555077A1 - Method of wide-layer surfacing - Google Patents

Abstract

The invention relates to a method of wide-layer surfacing and can be used for wide-layer surfacing under flux or in protective gases by an oscillating electrode using a filler lining melted plate. The purpose of the invention is to improve the quality of the surfacing by limiting the proportion of the base metal in the weld metal (20%) and increasing the productivity of the process by depositing a layer of the required thickness in one pass. A plate of thickness δ, similar in chemical composition to the desired composition of the deposited layer, of thickness H is superimposed on the product and fixed on it. Then fusing electrode diameter D _e, with amplitude oscillating across the width L of the plate at a constant rate U _s.c. , melt down the filler plate. The oscillating electrode is retained on the edges of the weld roller for 0.1 ... 2 s to better melt the adjacent rollers. The thickness of the plate is determined from the relationship δ = (0,56 ... 0,62) H mm, the welding current I = 170δ + (V _sc / 2) A, and welding speed V is equal to V _{n n} = 0, 6D _e V _p.k. / L m / h. 1 ill., 1 tab.

Description

The invention relates to electric arc welding, in particular to wide-layer submerged-arc welding or in protective gases by an oscillating electrode using a filler lining melted plate.

The purpose of the invention is to improve the quality of the deposited metal by limiting the proportion of the base metal in the deposited 20% and increasing the productivity of the process by depositing a layer of the required thickness in a single pass.

The essence of the method of wide-layer surfacing on the remelting filler

the plate consists in that a plate similar in chemical composition to the desired composition of the deposited layer with thickness H is applied to the product and fixed on it, then the surfacing is performed in a single pass with an electrode oscillating across the width of the plate with a constant velocity Vn k.

The electrode is held at the edges of the weld bead for 0.1 to 7 seconds to better fuse the adjacent rolls.

The thickness of the plate is determined from the ratio

Ј (0.56 - 0.6) N, mm,

SP

ate

Sl

about vl

J

welding current strength is defined as I 170 +, A

and the deposition rate is defined as

d .Vn

VM 0.6 m / h

where SC is the diameter of the welding electrode, MMJ

L is the amplitude of the transverse oscillations of the electrode.

The drawing schematically shows the weld product, the cross section.

The method is carried out as follows.

On the surface of the product 1 to be deposited, a filler plate 2 with a thickness {having a chemical composition corresponding to the required surfacing is applied, the plate 2 is welded along the contour to the product 1 and the welding is performed with a melting electrode having a high content of alloying elements compared with the composition of the required surfacing. The electrode oscillates with a constant transverse speed across the width of the weld roll 3 with an edge delay of 0.1-2 seconds for better fusion of the adjacent rolls. When a large surface surfacing applied sheet is pressed to the product with additional clamping beams or welded in several places with electric rivets. The values that determine the modes of surfacing are calculated using the formulas given.

The relationship between the thickness of the filler plate and the required surfacing height provides the fraction of the overlay of the remelted plate during the formation of the weld metal in the range of 70-76%.

The relationship between the welding current, the thickness of the filler plate and the speed of transverse oscillatory movement makes it possible to efficiently use the thermal power of the welding arc to completely melt the filler plate and minimize penetration of the product to a depth of 0.5-1 mm, which corresponds to the fraction of metal in the cladding not more than 20% .

ten

15

20

25

thirty

35

40

45

50

55

The table shows the experimental data on surfacing by wire with a diameter of 5 mm of steel grade 07H25N12G2T (GOST 2246-70) with the penetration of an overlay plate 5 mm thick made of steel 08H18N10T (GOST 5637-72) on the base metal of 16GS steel (GOST 5220- 79).

The relationship between the deposition rate, the speed of the transverse oscillatory movement and the diameter of the welding electrode ensures that the end of the electrode moves in such a way that, when transversely oscillated, its arc burns on the edge of the not yet hard metal of welding and a common weld pool is formed, contributing to the mixing of the metal of the bath and its everting and also obtaining a good appearance of the weld metal without flaking, sagging and gaps (see table, option 1).

The use of a filler plate in the form of a sheet of sufficiently accurate thickness and chemical composition with the stabilization of the main parameters of the surfacing modes allows to consistently obtain the minimum penetration of the product and to ensure the desired chemical composition of the surfacing in one pass due to the minimum dilution of the metal of the deposited metal with the product.

The speed of the transverse oscillatory movement of the electrode depends mainly on the diameter of the electrode and is approximately the same for different materials and amplitudes of the transverse oscillations and is selected within the range of 100-200 m / h. The amplitude of the transverse oscillations of the electrode is selected in the range of 30-100 mm. When choosing the values of 8 and I different from those calculated by the formulas, the quality of the deposition is unsatisfactory or the performance of the deposition decreases (see table, options 2 and 3).

The proposed method makes it possible to improve the quality of the deposited metal, to reduce the number of passes for obtaining a weld metal of uniform, predetermined chemical composition and the desired height of the weld metal to one.

Claims (1)

Invention Formula The method of wide-layer surfacing with a fused electrode over an additive five remelting plate, similar in chemical composition to the required composition of the deposited layer, which is superimposed on the weld surface and fixed on it, so that, in order to improve the quality of the weld metal by limiting the proportion of the base metal in the weld 20 % and increase the productivity of the process by making the deposited layer of the required thickness H in one pass, surfacing is carried out by an electrode oscillating with a constant speed of movement across the width of the VnK plate with adjustable time ENEMO electrode delay required for better fusion of adjacent rollers, I 550776 equal to 0.1-2 seconds at the edges of the weld bead, while the thickness of the remelting filler plate is determined from the ratio 8 (0.56 - 0.62) N, mm, welding current strength I is determined as V ten I $ 170 +, A, and the deposition rate VH set 15 V “O., m / h, where d3 is the diameter of the electrode, mm; L is the amplitude of the transverse oscillations of the electrode.