WO1991008859A1

WO1991008859A1 - Alignment apparatus for pipe welding

Info

Publication number: WO1991008859A1
Application number: PCT/FI1990/000299
Authority: WO
Inventors: Tauno KÖRMÖLÄINEN; Markku Poso; Pertti Lehto; Pekka Heikonen
Original assignee: Pemamek Oy
Priority date: 1989-12-18
Filing date: 1990-12-17
Publication date: 1991-06-27
Also published as: FI896043A; FI896043A0

Abstract

The invention relates to an alignment apparatus for the relative alignment of pipes preliminarily set on a welding table or a like and included in pipe panels (1) of heating boilers, said apparatus being adapted to align at any given time two adjacent pipes prior to their welding together in a welding automatic. The apparatus includes a pipe press (3) located substantially immediately upstream of a welding head (5), as well as a possible fin press (4). In order to secure a proper alignment of pipes also at the openings made in pipe panel (1), said alignment apparatus is also provided with at least two pre-presses (2) located upstream of pipe press (3).

Description

ALIGNMENT APPARATUS FOR PIPE WELDING

The present invention relates to an alignment apparatus for the mutual alignment of pipes preliminarily set on a welding table or a like for the pipe panels of heating boilers, the apparatus being adapted to align at any given time two ad¬ jacent pipes prior to the welding thereof in a welding automatic or a like to each other, either directly or by using a fin element fitted in between, particularly an apparatus for welding such a pipe panel, wherein at least some of the pipes are provided with one or more bend sections for making openings or recesses in a pipe panel, and said apparatus comprising pipe press sub¬ stantially directly upstream of a welding head or heads for aligning the pipes relative to each other and a possible fin press for positioning a fin element possi¬ bly fitted between the pipes, said pipe press and fin press being adapted together with a welding head or heads to travel relative to a pipe panel or, vice versa, a pipe panel is adapted to travel relative to said ele¬ ments in a manner that the pipe press is adapted to take hold of the pipes to be welded upstream of a welding head or heads.

A drawback in this type of prior known equipment is that the opening spots of pipe panels always require stopping of the apparatus and possibly relative fitting of the pipes with various extra tools before the.welding can be continued on the oppiste side of an opening.

An object of the invention is to provide an alignment apparatus which facilitates the continuous, automatical¬ ly controlled welding of pipe panels without stopping at the openings. According to the invention, this object is achieved in a manner that the apparatus is further provided with at least two pre-presses located upstream of a pipe press.

The pre-press consists of a rotatably journalled roller provided with a circumferential guide groove for guid¬ ing a pipe. The most preferred arrangement comprises a pre-press which consists of two rollers journalled rotatably about a common axle, said rollers being fitted relative to each other in a manner that the guide grooves align the pipes at a desired distance from each other.

The pre-presses and pipe press are arranged relative to each other in a manner that the guide- surfaces there¬ of center a pipe substantially on the same straight line and that the pre-presses and pipe press are spaced apart from each other.

In addition, the arrangement is such that both the pre¬ presses, a pipe press and a fin press are each pro¬ vided with independently controllable means for lift¬ ing or lowering relative to a pipe panel.

In an alignment apparatus of the invention, the pre--- presses bring the pipes almost to their proper posi¬ tion, whereby the final alignment element, i.e. a pipe press, only needs to effect the final alignment, which reduces the hazard of pipe damage. However, the most significant benefit gained by an alignment apparatus of the invention is that the welding operation can be fully automated also for openings. The lifting and lowering operations of pre-presses and pipe presses are programmed in a manner that at any given time at least two of said presses are holding the pipes being weld¬ ed in a fixed position. Thus, the pipes being weld¬ ed can be held continuously and controllably pressed against a welding top. This facilitates the continuous travelling of a welding head or heads relative to a pipe panel, since all functions can be programmed beforehand. Since the movement can proceed at a con¬ stant speed, a plurality of paired pipes can be welded simultaneously despite openings at different locations.

The use of pre-presses makes it possible to weld closer to an opening and also the controllable holding of a possible fin element between the pipes is facilitated by the use of pre-presses.

The invention will now be described by way of an example in more detail with reference made to the accompanying drawings, in which:

fig. 1 is a schematic side view of an alignment appa¬ ratus of the invention.

Fig. 2 shows a section along a line II-II in fig. 1.

Fig. 3 shows a section along a line III-III in fig. 1.

Fig. 4 shows a section along a line IV-IV in fig. 1.

Fig. 5 illustrates schematically the operation of an alignment apparatus at an opening.

The schematic side of fig. 1 illustrates a number of components participating in the welding operation of a pipe panel, generally designated by reference numeral 1. Reference numeral 2 indicates two pre-presses, reference numeral 3 a pipe press, reference numeral 4 a fin press, reference numeral 5 shows welding heads, and reference numeral 6 a slag crusher, all these com¬ ponents being carried by a common body, e.g. a portal, that can be carried in fig. 1 from right to left rela¬ tive to a pipe panel 1 being built on a fixed table. Each of said components can be vertically lifted and lowered.

The pre-press 2 is provided with a shaped roller 8 rotatably journalled relative to an axle 7. Each pre¬ press 2 is preferably provided with two such shaped rollers 8 journalled adjacent to each other, as shown in fig. 2. The circumference of shaped roller 8 is provided with a guide groove 9 for taking hold of a pipe 10. The guide groove 9 is designed so as to determine precisely the position of pipe 10 as the pipe 10 is pressed between a welding table and shaped roller 8.

The adjacent shaped rollers 8 are mounted relative to each other in a manner that a fin element 11 fitted between two pipes 10 is not subjected to excessive stress but deformations resulting from thermal ex¬ pansion and similar effects are released.

The structure of a pipe press 3 is best shown in fig. 3 and it is structurally and functionally quite similar to pre-press 2. The most- significant and es¬ sential difference is that the guide surfaces 13 of the shaped roller or shaped rollers 12 of pipe press 3 are designed so as to press pipes 10 and fin element 11 securely against each other. If necessary, between the shaped rollers 12 of pipe press 3 can be fitted a press disc 14 for guiding said fin element 11. The pre-press 2 can also be provided with such a press disc but it is generally sufficient that the circum¬ ference of shaped rollers extends to a suitable dis¬ tance for securing the position of fin element 11.

Fig. 4 illustrates a fin press 4 whose purpose is to press a fin element 11 to a final proper position be¬ tween pipes 10 prior to a welding operation effected by means of welding heads 5. The fin press 4 carries a rotatably journalled shaped roller 15 which is adapt¬ ed to press said fin element 11 against a supporting profile 16 mounted on a welding table.

Operation of the apparatus is best shown in fig. 5. Presses 2, 3, 4 and welding heads 5 as well as slag crusher 6 are each lifted in turn prior to a pipe bend 17 and respectively lowered after the pipe bend. The guiding of pipes 10 is performed at any given time simultaneously by at least two pre-presses 2 or one pre-press 2 and one pipe press 3.

When the leading pre-press 2 arrives at a position ad¬ jacent to a pipe bend 17 made at an opening, said pre¬ press is automatically lifted up and pipes 10 remain to be supported by the other pre-press 2 and pipe press 3. At the following stage, the leading pre-press 2 is lowered down, whereafter the other pre-press 2 is in turn lifted up. When both pre-presses 2 are lower¬ ed down, said pipe press 3 is lifted up (fig. 5b) . Finally, as the welding operation has proceeded suf¬ ficiently close to pipe bend 17, said fin press 4 and welding heads 5 are lifted up and finally said slag crusher 6 is lifted up.

Claims

1. An alignment apparatus for the relative alignment of pipes (10) preliminarily set on a welding table or a like for pipe panels (1) of heating boilers, said apparatus being adapted to align at any given time two adjacent pipes (10) prior to the welding thereof in a welding automatic or a like to each other, either di¬ rectly or by using a fin element (11) fitted in be¬ tween, particularly an apparatus for welding such a pipe panel, wherein at least some of the pipes (10) are provided with one or more bend sections (17) for making openings or recesses in a pipe panel, and said appratus comprising a pipe press (3) located substantial¬ ly directly upstream of a welding head or heads (5) for aligning pipes (10) relative to each other and a possible fin press (4) for positioning a fin element

(11) possibly fitted between pipes (1) , said pipe press

(3) and fin press (4) being adapted together with weld¬ ing head or heads (5) to travel relative to a pipe panel or, vice versa, a pipe panel is adapted to travel relative to said components in a manner that said pipe press (3) is adapted to take hold of pipes (10) to be welded together upstream of welding head or heads (5) , c h a r a c t e r i z e d in that the apparatus is further provided with at least two pre-presses (2) mounted upstream of pipe press (3) , said pre-presses

(2) being adapted to ^"bring pipes (10) almost to their proper position in a manner that the components to be joined together are not subjected at said pre-press

(2) to excessive stress but deformations resulting from thermal expansion and corresponding effects are released, and that said pipe press (3) is only adapted to perform the final alignment.

2. An apparatus as set forth in claim 1, c h a r - a c t e r i z e d in that said pre-press (2) comprises a rotatably journalled roller (8) provided with a circumferential groove (9) for guiding a pipe (10) .

3. An apparatus as set forth in claim 1 or 2, c h a r ¬ a c t e r i z e d in that said pre-press (2) comprises two rollers (8) journalled rotatably about a common axle (7), said rollers being mounted relative to each other in a manner that said guide grooves (9) align pipes (10) at a desired distance from each other.

4. An apparatus as set forth in any of claims 1 - 3, c h a r a c t e r i z e d in that said pre-presses (2) and pipe press (3) are mounted relative to each other in a manner that their guide surfaces (9, 13) center a pipe (10) on a substantially common straight line, and that pre-presses (2) and pipe press (3) are spaced apart from each other.

5. An apparatus as set forth in any of claims 1 - 4, c h a r a c t e r i z e d in that both pre-presses (2) , pipe press (3) and fin press (4) are each provided with independently controllable elements for lifting or lowering relative to a pipe panel (1) .

6. An apparatus as set forth in any of claims 1 - 5, c h a r a c t e r i z e d in that the guiding of pipes (10) is adapted at any given time to be simultaneously performed by at least two presses (2, 3) .