RU1810257C - Method and device for welding up small diameter blind holes - Google Patents

Abstract

Usage: for welding blind holes of small diameters in products of large thickness, especially from liquid materials. The essence of the method: non-consumable electrode 3 is installed on the periphery of the hole with a gap relative to its walls. The wire 9 is fed along this hole, bending its working part to the angle a of the hole 1, the melting of which begins from the bottom 6 after pointing the weld pool 8, while simultaneously moving the electrode 3 and wire 9 in a spiral upward. Welding of the hole 1 is carried out in separate batches of two to three passes, with the metal of the weld pool 8 of each series cooled to 30-40 ° C. In the process I. Of the first series, the wire is fed into the front of the weld pool 8 with an offset S from the wall to the center of the hole i by 1.5-2.0 mm. When welding the following series with gradual displacement 1. . . (mm) from the position of the wire in the previous series towards the tail of the weld pool 8 to its feeding in the last final

Description

series in the tail section, while the arc 7 is displaced in the welding direction, and the non-consumable electrode 3 is directed into the corner of the hole parallel to the filler wire 9 L-length of the weld pool (mm); b - deposition height in each series of passes (mm); h is the height of the melt hole. The device for implementing the method comprises a housing in which a drive electrode holder with a replaceable tip and a channel for supplying filler wire 9 is placed. The sleeve is fixed to the electrode holder with the possibility of a fixed rotation around a non-melting electrode. A replaceable tip is rigidly fixed in the inclined channel of the sleeve, and a non-consumable electrode is rigidly fixed in the electrode holder socket. 2 s.p. f-ly, 7 ill. 4 tab. .

The invention relates to welding, in particular to automatic electric arc welding in a shielding gas environment, and can be used for welding deep blind holes of small diameter in any industry.

The aim of the invention is to improve the quality of small diameter fused holes in the manufacture of large-thickness products from liquid metals, such as titanium and its alloys, by eliminating non-fusion at the walls of the hole and the formation of the last imperfections and voids by increasing the amount of tagel introduced into hole walls and redistribution of liquid metal not only across the weld pool, but also along it during each pass, as well as fixing the weld pool metal after each series.

Fig. 1 shows the placement of a non-plugged electrode with filler wire inside a blind hole of small diameter of a product of large thickness; in FIG. 2 - the same top view; in FIG. 3 - cyclogram of the proposed welding process.

In the drawings indicated:

VCB-VBP — welding speed or rotation speed of the electrode holder in rpm; / np filler wire feed rate, m / h; 1sv - welding current A; sv (s} - welding current of the first series, A; icepc) - welding current of the second series, A; h is the height of the brewed hole in the product, mm; a - the angle between the wall of the hole and the bottom, the hail, which is equal to 900 before welding and changes after the first series of passes; L- length of the weld pool, mm; Si, 82. Ss, S4, Ss — displacement of the end of the filler wire from the wall of the hole to its center (across the weld pool), mm. It, (2.1zL4, 5 placement of the end of the filler wire from the front of the weld pool to its tail in each series relative to its position in the previous series; tio6 - time

one revolution of the electrode holder, s; Bx

deposited layer cooling time. each series, min; VCB (IC) VBP (IC) welding speed of the first series, rpm, yCB (2c) vBp (2c) - welding speed of the second series, rpm; P

- the number of passes in each surfacing series and the number of surfacing series; K arc length, mm .: l; The proposed method of welding deaf

holes of small diameter in products of large thickness from fluid materials are as follows.

In the opening 1 of the article 2 (see Fig. 1), a non-floating

electrode 3 with a gap relative to the walls of the 4.5 holes, directing its working part to an angle of 90 ° between the opposite wall 5 of the hole 1 and its bottom 6 at a distance from this bottom equal to the required length K of the arc 7. The hole is blown with protective gas argon, excite the arc 7, which melts the bottom of the hole 1 and the wall 5, form | weld pool B with a fixed electrode 3. The time of aiming the weld pool B of the required size is set in each case, depending on the Material of item 2, the diameter and depth of the hole and the parameters of the mode.

After locating a local weld pool B at the bottom of $ B, it is fed with filler wire and a loop at a speed Vnp at a distance of Si (see FIG. 2) (offset) from the wall 5 of hole 1 to its center (see FIG. 1) at the same time move upward in a spiral: a certain step dm (see Fig. 3) and with a speed vBpOc) vcB (fc) is not floating from electrode 3 and this wire, feeding it to the head part of C8a | eye bath 8 (cm .

FIG. 2} and etched it together with the electrode 3 to an angle a -90 ° ne | Eed by the first passage between the bottom 6 of the hole 1 and the wall 5 with the displacement of the arc 7 in the welding direction. With this relative position of the electrode

3 and filler wire perform 2-3

a series of welding passes of the first series at a speed

wire feed vnp rotation speed (welding) VBP (| C) VCB (| C) and welding current ICB (IC). The second series of passes is also performed in an amount of 2-3 passes at a wire feed speed of Vnp, a rotation speed of vBp (2c) VcB (2c) and a welding current of sv (2c) and so on until the final series of passes. It should be noted that the displacement S from the first series to the final series varies within (1.5-2.0) mm; If this distance is more than 2 mm, the filler wire 9 will freeze from the less heated part of it to the weld pool 8 due to heat transfer to the wire 9, and if it is less than 1.5 mm, it will take a lot of heat from the ingot arc 7 and reduce its thermal efficiency. After the last pass of the first series has been completed, the arc is quenched and the metal of the weld pool (see Fig. 2) is cooled toxn (30-40) ° C. It should be noted that below 30 °, the surfacing metal should not be cooled, since further the cooling process is much slower, which sharply reduces the process productivity, and at a temperature above 40 ° C the size of the weld pool is still significant. An optical system provides visual inspection. Then, 2-3 passes of the second and subsequent series are carried out with a preliminary shift of $ 2. Зз etc. (see Fig. 2) the end of the filler wire 9 in front of each series from the wall 4.5 of the hole V, towards its center 0-0 (see Fig. 1) and with an offset of h, 12, 1z, etc. d. (see Fig. 2) from the position of its end in the previous series, but already towards the tail of the weld pool. It should be noted that the displacements are And, 12, etc. previously determined from experimentally derived ratio 1

L b

 Ih -f BY (mm) where Alina of the weld pool in mm; b - deposition height of each series of passes, (mm); h is the depth of the melt hole (mm).

If this offset is less than

1 yi. vu (mm), the current of the final series of the weld pool will increase significantly, and at higher values of x than I, freezing of the welding wire 9 to the bath 8 can again occur. Thus, before each series of surfacing, the position of the filler wire 9 is strictly determined with respect to the non-floating electrode 3 and all 2-3 passes of each series, they are performed with predetermined S and I values for this series.

The change in the place of entry of the filler wire 9 in the direction of the tail of the weld pool 8 before each series of passes is due to a decrease in heat removal as the hole 1 is filled and, accordingly, an increase in the volume of the weld pool 8. In this case, the molten metal of the weld pool leaks under the arc 7, which leads to non-fusion of the weld pool 8 with walls 4.5 of the hole 1.

When the insertion point of the filler wire 9 is shifted in the direction of the tail of the weld pool sequentially by .1.1, 2, etc. the liquid metal is frozen and drawn out from under the arc 7, which makes it possible to reliably melt the walls 4 5 of the hole 1 by the arc 7 and eliminate non-fusion at this point.

Example 1.1. The tests were carried out on a prototype of a 55 / M290 automatic welding machine for welding deep holes with a non-consumable electrode with the filler wire SV-23. Holes with a diameter of 20 mm and a depth of mm were welded in the lower position in PT-ZV titanium alloy products. The 55 / W90 machine was specially designed to weld these holes and allowed the interposition of the filler wire and the non-consumable electrode to change between themselves and the walls of the weld hole. As control equipment, CA 230M1, a power source TIR-ZOODM1, was used.

EXAMPLE 2. Welding was carried out using three passes in each series. Mutual arrangement of the non-melting electrode and filler wire across the weld pool and along each welding passage of the same series when welding. In the first series of passes for welding the holes, the electrode was set at an angle of 90 ° between the bottom and the wall of the hole, an arc was excited, 5 mm, and after pointing the weld pool, the electrode began to rotate while the filler wire was fed into the head of the weld pool with its offset S from the hole wall by 2 , 0 mm and from the melting front to the tail of the weld pool by a value of 30 mm, moving everything upward in a spiral. After performing three passes in this way, welding was stopped, the machine was pulled out of the hole, cooling the resulting seam to 40 ° C for 30 minutes and controlling it simultaneously using an optical system. The second series of three passes was carried out with the filler wire shifted relative to the head of the weld pool of the first series to its tail part by

value

L-b

(mm), where L is the length

f + y

weld pool (mm); b - deposition height in each series (mm); h - hole depth (mm). When welding at the conditions indicated below, the bath length was 18 mm, i.e.

18 9 1 dp then 3 mm (deposition height of one

the passage was 3 mm, and one series 9 mm). 45 mm high hole; brewed 10 for 5 series. After each passage of each series was performed, as the hole was filled, the electrode was placed upward using the ER-254 automatic arc voltage control system. The subsequent 15 series were performed in a similar way, shifting the position of the filler wire from series to series towards the tail of the weld pool by 3.4 mm, and when the final series was performed, the wire was fed into the tail

 bathtubs. :.; /.-. . ..-,. ; , ..:. V. -. .,.,: U ;, .. -Example 3 - U -. . : .L:: ...

. The welding mode was set in the following -: range: ..; . ; : ..: 25 ... Welding current, A:: 240-260

Welding speed, rpm8-12,

, Feed rate. ... -..; .-. : V. :. v; v,. .. wire m / h:, -........, V 20-40 Diameter of electrode mm 3 30 Diameter of filler. V

WIRES, MM; -; :, - .. 1,2.

Example 4. Comparative tests of the method were carried out with various embodiments and mode parameters and 35; Evaluation of the technical characteristics of the process (productivity, quality, formation of a circuit, defects, etc.), the results of which are shown in Table 1 - 4.- ..;: ... J ::. ;;, hP, L /;.,. 40

Thus, the best quality and productivity of the process of welding blind holes of small diameter on products made of fluid metals is achieved by providing two or three passes in each 45 series, cooling each series to 30-40 ° С, and displacing the feed wire from the wall of the hole (1, 5-2.0) mm and shifting it from series to series to the tail of the weld L .... ,.., fifty

bath for the amount of {

h 4-b

mm, where L is the length of the weld pool (mm) ;, b is the surfacing height of each series (mm); h is the height of the hole (mm). A device for carrying out the proposed method for welding blind deaf holes of small diameter is illustrated in the following drawings.

On Fig / 4 shows a device for welding blind holes; "scarlet diameter

.

(section BB, in Fig. 7) passing through the longitudinal axis of the interchangeable tip and the non-melting electrode; in FIG. .5 - section AA in FIG. 6. Electrode-containing and replaceable tip passing through the longitudinal axis; in FIG. 6 is a view D in FIG. 4; in FIG. 7 is a section BB in FIG. 5. In FIG. 4 - 7 the following designations are given: / 3 - the angle between the longitudinal axis of the electrode holder and the supplied filler wire or non-consumable electrode, deg. K is the length of the arc, mm; S is the distance with the longitudinal axis of the direct wire and the wall of the melt hole 1 in the product2. : v ;; ./- ;;: v .-: ..-; U: -. TH -. ::.: (-:,:

The device comprises (see Fig. 4) a housing (not shown) in which the drive electro-holder 10 with a replaceable tip 11 and an insulated channel 12 for feeding the filler wire 9 and the sleeve 13 with the channel for feeding the same wire 9 inclined relative to the axis is placed N rotation (see Fig. 5); the electric holder W The sleeve 13 with an oblique channel is mounted on an electric holder 10 with the possibility of rotation in rotation around the axis of the non-melting electrode 3. For which an arcuate groove 14 is made in it (see Fig. 6) parallel to axis 1-1 (see FIG. 5 ) and guides 15 and 16 parallel to the same axis are passed in the form of screws and sealed in the electrode holder 10 with no thread, and the sleeve 13 is freely placed in the socket 17 of the electrode 10. The replaceable tip 11 is fixed rigidly through the insulator in the sleeve channel 13 of the sleeve 13 , the channel axis of which is concentric to its axis and coaxial on the axis lt of the channel for supplying filler wire 9 with electrode-containing tO. At the same time, the non-consumable electrode Zc is fixed by screw 18 (see Fig. 6) in the socket 19 of the electrode holder 10, made parallel to the inclined channel (axis NI) of the sleeve 13 and freely passed through the through arcuate groove 20 made in the same sleeve 13 parallel to the channel (- axis), in which the tip And is interchangeably fixed, the axis of symmetry of which (see FIG. 6) is concentric with the axis of symmetry of the other groove 14. In addition, holes 21, 22, etc. are made in the sleeve 13. to pass argon shielding gas.

The device operates as follows (see Fig. 1).

The body 2 is installed on the product 2 (to hell, not shown) of the proposed device so that the drive electrode holder 10 with a replaceable tip 11 mounted in the sleeve 13, through the insulated coaxial channels of which along the axis HI and II-III filler wire 9 , and a non-melting electrode 3, fixed in the socket 19 by a screw 18 parallel to the axis II-II1 and freely passed through the groove 20 in the sleeve 13 parallel to the same axis II-III, was placed in the hole 1 to be welded, with a gap relative to its walls 4 and 5 coaxial to the axis of the hole and its axis of rotation - (see Figure 5..); having previously fixed the non-melting electrode 3 to such a length that, when era is placed in the hole 1, the distance between its end and bottom 6 is equal to the arc gap K, and the end of the filler wire is directed at an angle a at a distance of 5 mm from the wall 5 of the hole (see Fig. 2). After such adjustment, the device body is clamped on the product 2. Now, the hole 1 is purged with shielding gas and Ice is turned on (see Fig. 3), forming an arc 7 to melt the metal of the bottom 6 and point the local weld pool 8. After the weld pool 8 is turned on, turn on filler wire 9 was fed through channel 11 with an UPOD speed and the electrode holder 10 was spirally rotated upward at a certain step with a speed vBp VCB, surfaced in three passes of the first series with an arc offset in the welding direction and wire J9 in front part st weld pool 8. After performing the first series Electrode 10 is raised and withdrawn from the holes t, withdrawn towards the weld metal, and cooled to 30-40 ° C. At the same time, an optical system (to hell, not shown) is visually monitored. Then, if necessary, with the help of screw 18 adjust the length of the electrode 3 and clamp it again in the socket 19. Then, loosening the guide screws 15 and 16, turn the sleeve 13 in the socket 17 of the electrode holder 10 along the grooves 20 and 14 around the electrode 3 to the side rear of the weld pool

l2 / L, LA (mm), where L is the length of the welding

bath / mm; b - deposition height in each series of passes, mm; h is the depth of the fused hole, mm (the value of which was previously determined experimentally on the samples), relative to the position of the end of the filler wire 9 along the weld pool 8 of the first series of passes, at the same time, the distance $ 2 of the end of the welding wire from the walls 4, 5 is automatically set holes 1. Then, with the help of screws 15 and 16, the sleeve 13 is pressed against the end of the electrode holder 10. Now the optical system is removed from the hole 1 of the article 2.. The electrode holder 10 is brought to the hole 1, again lowered into it, setting the requirement distance K between the end of electrode 3 and the metal surface of the deposited previous series. Again, the electrode holder 10 is fixed in the hole 1, pre-installation simultaneously with the offset .1 and fixing

the end of the filler wire 9 at a distance S from the wall 4 of hole 1, Now blow hole 1 of article 2 through holes 21 and 22 (see Fig. 6), include welding current 1Cb, filler wire 9 UPOD and spiral upward electrode holder 10 with a certain step and welding speed, welded the next three passes of the second series. Then everything repeats:

likewise from the sequence diagram in FIG. 3 carry out welding of the third and subsequent series, feeding in the last series filler wire 9 into the tail of the weld pool 8 according to FIG. 2 and so

by completing the welding of hole 1.

Thus, the proposed method and device in comparison with the prototype can improve the quality of the welded joint by eliminating non-fusion

metal surfacing at the walls of holes, voids between aisles, non-fusion, etc. due to the fact that they allow during the welding process to regulate the volume of liquid metal of each pass and the heat introduced into it

 not only across the weld pool, but also along, since the sleeve with a replaceable tip, through which the filler wire is rotated around the non-consumable electrode, the distance between the ends of the electrode and wire is changed not only across the hole, but also along it, since this happens the intersection of their axes in space.

45

Claims (2)

1. The method of welding blind holes of small diameter, in which a non-consumable electrode is installed around the periphery of the hole with a gap relative to its walls, the filler wire is fed along the hole with a bent working part into the corner of the hole, and the fusion of the hole begins from the bottom after pointing the weld pool by moving at the same time, the electrode and the wire spiral upward, characterized in that, in order to improve the quality when welding holes of small diameter by introducing more heat into the walls of the hole and redistribution of the volume of liquid metal in each pass, welding of the hole is carried out in separate series of two or three passes with cooling the metal of the weld pool of each series to 30-40 ° C, during the welding of the first series, the wire is fed into the finished part of the weld pool with an offset from the wall to the center of the hole by 1.5-2.0 mm, and when welding subsequent series with a gradual displacement by . L b value | / h + b) where L is the length of the weld pool, mm; b - deposition height in each series of passes, mm; h is the depth of the hole to be melted, mm, from the position of the wire in the previous series towards the tail of the weld pool to its feed into the tail during the final series, while the working part of the non-melting electrode is also directed to the corner of the hole with arc mixing in the direction welding. 2. Device for welding blind holes of small diameter, comprising a housing in which there is a drive electrode holder with a replaceable tip and an insulated channel for supplying filler wire, as well as a sleeve for supplying filler wire to a non-consumable electrode, Furthermore, in order to improve quality, the sleeve with the inclined channel is fixed to the electrode holder with the possibility of a fixed rotation around the non-floating electrode, the replaceable tip is rigidly fixed in the sleeve channel, the axis of the tip channel is concentric with its axis and coaxial with the axis of the filler wire of the filler wire of the electrode holder, and the non-consumable electrode is rigidly fixed in the socket of the electrode holder, made parallel inclined channel of the sleeve, and freely passed through a through arcuate groove made in the sleeve parallel to the channel in which the interchangeable tip is embedded. Table 1 table 2 The amount of displacement of the wire from the series to the series along the wa - to us to her hobby. 7 fate of the um: The increase in the volume of the bath "with the end of the welding of the hole, the formation of undermates:. ;;, ..:; : --- adv.zh: ;; X: - and Table 3 Table 4 (f "t .; m $ m  Fsf4 0 Volume increase bath to the end weld holes; freezing provo ok keanye, g B-b