JPS5831279B2 - Kakupipe Yousetsuyouuraatesouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a backing device for welding square pipes used for building columns and the like.

Square pipes with a rectangular cross section as shown in FIG. 1 are used for pillars of buildings.

This square pipe is made by butting strip steel plates 1a and Ib bent into a U-shape with a thickness of 6 to 16 rIrrrL or U-shaped steel made by rolling to form a rectangle as shown in the figure, and welding the butt portions.

-Side length is 250wm, 300rrm, 350r
rrm, etc., and submerged arc welding is generally used for welding.

For this reason, it is necessary to provide a backing when welding, and a width of 25 mm is required.
~301rtrrL and a thickness of about 5y++m are used as the backing materials 2a and 2b.

The backing materials 2a and 2b are alternately temporarily attached to both open ends of one of the steel strips ia and lb or to one open end of both steel plates (indicated by reference numerals 3a and 3b), and then the two steel plates are butted, The abutting portions are temporarily attached from the surface side at appropriate intervals (represented by reference numerals 4a and 4b), and then the actual welding begins.

However, these tacking 3a and 3b are difficult to perform because the length of the square pipe is 12 to 16 m, and the work is done on the inner surface of a band shaped like a U-shape.Furthermore, tacking requires a large number of parts. Therefore, it is a very time-consuming job.

The present invention improves this point by providing a welding method, particularly a backing device thereof, which eliminates the need for tacking 3a and 3b.
The purpose is to enable welding of square pipes to be carried out efficiently, quickly and appropriately.

Next, the present invention will be described in detail with reference to Examples.

2 to 4 show an embodiment of the backing device of the present invention,
FIG. 2 is a longitudinal sectional view, FIG. 3 is a side view, and FIG. 4 is a partial perspective view.

In these figures, reference numeral 10 denotes an elongated truck, which has a length longer than the entire length of the square pipe, and is equipped with a large number of running wheels 11 at appropriate intervals (for example, 600 wrL).

A plurality of columns 12 are fixed on the trolley 10 at appropriate intervals (for example, 1.5 m), and a handle 13 is fixed to the upper end of each column.

The handle 13 that forms the support mechanism of the backing materials 2a and 2b also has the same length as the square pipe, and a base plate 15 is housed therein via a spacing piece 14, and a hose 16 is housed on the base plate 15. .

A support plate 1 is provided at the open end of the handle 13 so as to cover it.
7 is placed, positioning protrusions 17a and 17b are provided in the center of this support plate, and the backing material 2a is placed between these protrusions.

Each of the columns 12 of the truck 10 is provided with a through hole 12a, and the operating rod 20 is disposed through the through hole 12a.

This operating rod is also the same as the base plate 15, hose 16, support plate 17, etc. (has a length equal to or longer than the square pipe).

A telescopic arm mechanism 21 for center positioning is attached between the operating rod 20 and each support column 12.

This telescopic arm mechanism 21 includes a roller 21a. 21b, and two rotatable arms 21c, 21d and 21e, 21f, one end of which is pivotally connected to the rotation axis of these rollers, and the other end of one of these arms 21c, 21e is operated by a pin 22. The other arm 21d 2 is pivotally connected to the rod 20.
The other end of 1f is pivotally connected to the bearing portion 12b of the support column 12 by a pin 23.

This pin 23 is located on the center of the through hole 12a.

Next, how to use this backing device will be explained.

The steel strips 1a and 1b bent into a U-shape are butted together to form a rectangular cross-section as shown in FIG. 2, and a backing device is inserted inside the steel strips 1a and 1b.

At this time, the operating rod 20 of the backing device is pushed in the direction of arrow F1 in FIG. 4, leaving the rollers 21a and 21b of the telescopic arm mechanism in a retracted state.

Further, air is not pressurized into the hose 16, so that the hose is contracted, and the support plate 17 is left resting on the upper edge of the tub-shaped body 13.

In this state, the outer diameter of this backing device is smaller than the inner diameter of the square pipe.

Therefore, a backing material 2a is placed between the protrusions 17a and 17b of the support plate 17.
When placed on the steel plates 1a and 1b and pushed into the steel plates 1a and Ib from one end, this backing device can be easily inserted into the butted steel plates 1a and 1b, that is, the rectangular pipe-shaped body.

At this time, the wheel 11 rolls on the inner surface of the bottom of the steel plates 1a and 1b,
Facilitates insertion of backing device.

The steel plates 1a and 1b are tightened with appropriate fasteners so as not to destroy their abutted state, or are further temporarily attached from the surface side (4a, 4b).

When the backing device is completely inserted into the steel plates 1a and Ib, the operating rod 20 is stretched 9 in the direction opposite to the arrow F1.

With this operation, the arms 21c to 21f are expanded outwardly as shown by dotted arrows, and the rollers 21a and 21b are pushed out.

As a result, the rollers 21a and 21b come into contact with the inner surfaces of the steel plates 1a and 1b, and since 21c to 21f form a parallelogram, the opposing apex, here the line connecting the pins 22 and 23, is the roller 21a.

According to the distance between 2Ib, the inner surface of the square pipe is divided into two equal parts.

Since the pins 22, 23, the through holes 12a of the pillars 12, and the operating rod 20 are aligned with the center line of the backing material 2a, the center position of the backing device can be aligned by expanding the rollers 21a, 21b. This allows the backing material 2a to be correctly brought into contact with the abutting portion of the U-shaped steel plates 1a and 1b.

The backing material is brought into contact with this abutting portion by feeding compressed air into the hose 16 to expand it and pushing up the support plate 17.

After the backing material 2a is properly brought into contact with the butt lower surfaces of the steel plates 1a and Ib, the temporary attachment 4a is still performed.

If step 4b has not yet been completed, perform this step, then sprinkle flux from the surface side and perform submerged arc welding.

After welding is completed, push the operating rod 20 in the direction of the arrow F1 again to retract the arms 21c to 21f and the rollers 21a, 21b, remove the compressed air from the hose 16, lower the support plate 17 by its own weight, and move the cart 10 to the steel plate 1a, Pull it out from inside Ib.

If the pull-out direction of the trolley 10 is set in the direction of arrow F1, this pull-out operation can be performed by holding the handle (not shown) attached to the end of the operating rod 20 and pulling the operating rod. It can be performed in common with the contraction operation of ~21f.

The backing operation for the backing material 2b on the other side is performed by inverting the box-shaped steel plates 1a and 1b, which are welded on one side, by 1800 degrees, and then
Place the backing material 2b on the protrusions 17a and 17b of 7, and use the same operation as before to attach the backing device to the steel plate la.

This is done by inserting it into 1b.

As is clear from the above description, according to the present invention, there is no need to temporarily attach the backing materials 3a and 3b, and square pipes can be efficiently and quickly welded.

In addition, center positioning can be performed simply by moving the operating rod back and forth, and the backing material can be accurately positioned at the welding part.

Moreover, the arms 21c to 21f forming a parallelogram form the roller 21a by increasing the length of each arm.

21b can be made considerably longer, and the height of the base plate 15 can be easily changed by appropriate means such as changing the height of the spacing piece 14, so that the height at which the support plate 17 is pushed up by the hose 16 can be increased. As a result, the present backing device can be applied to welding square pipes of various sizes.

Although the rollers 21a and 21b at the tips of the telescopic arm mechanism 21 reduce contact friction with the inner surface of the square pipe, they may be omitted.

In addition, in the illustrated embodiment, the telescopic arm mechanism 21 moves the trolley 10, the tub-shaped body 13, etc. as a whole to align the centers; The operating rod and the telescoping arm mechanism may be attached to the tub-shaped body so that only the handle, that is, the backing material support mechanism, is driven by the telescoping arm mechanism to align the center.

[Brief explanation of drawings]

Figure 1 is an end view explaining the welding method for square pipes, Figure 2 is
3 and 4 are a cross-sectional view, a side view, and a partial perspective view showing one embodiment of the backing device of the present invention. In the drawing, 1a and 1b are strip plates, 1o is a trolley, and 4a. 4b is a butt weld, 2a and 2b are backing members, 17 is a support plate, 17a and 17b are projections thereof, 13 to 17 are backing member support mechanisms, 2o is an operating rod, and 21 is a telescopic arm mechanism.

Claims (1)

[Claims] 1. A cart with elongated wheels that is inserted into the inside of a square pipe-shaped body, and a butt welded part that is attached to the trolley and extends along the longitudinal direction of the square pipe-shaped body at approximately the center of the surface of the square pipe-shaped body. a backing material support mechanism having a support plate that supports a backing material that is movable up and down and has a projection for positioning the backing material; A plurality of operating rods are attached to the operating rod at intervals, and as the operating rod moves back and forth, it protrudes in a direction perpendicular to the longitudinal direction and comes into contact with the inner surface of the square pipe, thereby aligning the center of the backing material. A backing device for square pipe welding, characterized in that it is equipped with an extendable arm mechanism assembled in a parallelogram shape.