JPS6117597B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for stably holding and centering tubes when welding the tubes against each other.

Normally, when butt welding the end faces of steel pipes, it is desirable to perform circumferential welding with as little misalignment between the butt parts as possible. misunderstandings are unavoidable. Therefore, welding jigs have been used to reliably hold the abutting portions of such pipes and correct misalignment (centering).

For example, as a conventional pipe welding jig,
One example is the one shown in Publication No. 14347, and this jig is provided with a tube receiving protrusion on the inner surface of an enclosure in which two half rings are connected to each other, and a plurality of presses that can move inwardly and retractably are provided on the enclosure. Consists of bolts attached. However, this welding jig has the following problems.

Since the pipes to be butt-welded are limited to a combination of straight pipes and straight pipes, the applicable pipe types are narrow.

The pipe moves when the bolt is pressed, and the ability to adjust the root gap of the bevel is poor.

Since the tip of the pressing bolt directly hits the pipe surface and rotational force is applied, the more the pipe thickness increases, the more indentation occurs.

When the pressure bolt is tightened, a reaction force acts on the flange portion, resulting in significant structural deformation of the flange portion, resulting in breakage or weakening of the pressing force of the pressure bolt.

The present invention solves the problems of the prior art described above,
It is an object of the present invention to provide a holding device for pipe welding that can be applied to irregularly shaped pipes other than straight pipes, cut pipes, etc., has high centering accuracy, and does not leave impressions on the pipe.

In order to achieve this object, the present invention has a configuration in which a guide member is provided inside one side of the two arcuate clamp bodies, and a loose cap is attached to the tip of a pressing bolt that is provided on the clamp body so as to be able to move forward and backward. It is a feature of

Embodiments of the present invention will be described below based on the drawings.

What is shown in FIG. 1 is a semicircular clamp body constituting the tube holding device of the present invention, which is used in combination with a similar clamp body to surround the tube end. As shown in the figure, the clamp body 1 uses a single steel plate, and has notches 2 formed at intervals in the longitudinal direction of the center of the plate.
The clamp body 1 is formed into an arc shape (semicircular shape in the figure), and coupling members 3 are attached to both ends of the clamp body 1 to connect the clamp bodies to each other.

Plate-shaped guide members 4 are fixed or provided with guide bolts at regular intervals on one side of the inner side of the clamp body 1, and are movable back and forth in the radial direction of the clamp body 1 and arranged in two rows in the circumferential direction of the clamp body. A pressing bolt 5 is provided. As shown in FIG. 2, in order to attach the bolt 5 to the clamp body 1 so that it can move forward and backward,
For example, a hole may be bored in the clamp body 1, a bush 6 may be mounted in the hole, and the press bolt 5 may be screwed into the bush 6.

Further, a loose cap 7 is attached to the tip of the pressing bolt 5 (the part that contacts the tubular body), which moves along with the bolt's axial movement but does not transmit rotation about the bolt's axis. As an example of this loose cap 7, as shown in FIG. 3A, the cap 7a is locked in a groove 9 formed at the tip of the bolt 5 with a set screw 8, or as shown in FIG. A cap 7b having a groove 11 into which a protrusion 10 having a T-shaped cross section protruding from the tip of the cap 5 may be used. In addition, in FIGS. 3A and 3B, the tip of the bolt 5 or the tip surface of the protrusion 10 is formed in a spherical shape,
This is because the cap 7 can be tilted freely in any direction with respect to the bolt axis, making it possible to apply it to irregularly shaped pipes and jointed pipes.

Also, a coupling tool 3 for interconnecting the clamp bodies 1 is provided.
Although it is sufficient to use bolts and nuts to fasten the flanges provided overhanging from both ends of the clamp body 1, considering that it is advantageous in terms of strength and has good workability, the connecting means shown in Fig. 4 is adopted. It is desirable to do so.

That is, as shown in FIGS. 4A and 4B and FIG. do. The bolt 13 is inserted into the end of the flange portion of the other clamp body that corresponds to the hinge bolt 13.
A recess 14 is provided for the nut to engage. Therefore, when the flanges are to be connected to each other, the hinge bolt 13 is rotated upward as shown in FIG. 5 to fit into the recess 14, and then the nut portion is tightened.

Although the guide member 4 provided inside the clamp body 1 is formed into a plate shape, the guide member 4 has a guiding function that simply determines the approximate position of the clamp body when clamping a pipe, and does not require pressure. When the bolts 5 are tightened, the guide member 4 does not come into contact with the pipe surface. Therefore, the guide member 4 may have a shape other than a plate, and in some cases, it may be replaced with a bolt that can move forward and backward. Further, the number of pressing bolts and guide members can be arbitrarily increased or decreased depending on the diameter of the pipe.

Next, the operation of the holding device of the present invention constructed as described above will be explained.

FIG. 5 shows an example in which a straight pipe 15A and a deformed pipe (elbow in the figure) 15B are butt welded. First, as shown in the figure, the side of the clamp body 1 on which the guide member 4 is provided is set on the straight pipe 15A or the elbow 15B, and the upper and lower semicircular clamp bodies are connected with the hinge bolt 13. Of course,
Alternatively, the pair of clamp bodies may be connected in a circular manner in advance and then fitted into the tube body. Next, the position of the tube end is adjusted to be approximately at the center of the notch 2, and then the press bolt 5 is tightened to fix the clamp body 1. In this state, connect the other pipe (elbow 15B in the diagram)
is inserted from one side (right side) of the circular clamp body, and the bolt 5 is tightened to fix the tube 15B. In this case, as shown in the figure, the bolt 5 on the bent pipe side is
A loose cap 7 at the tip rotates according to the bending of the pipe to perform good tightening. The gap and misalignment between the notch 2 of the clamp body 1 and the bevel at the pipe end are controlled using a measuring instrument, and by tightening or reducing the pressure bolt 5, the bevel conditions are adjusted and the condition is adjusted to an appropriate state. do.

The present invention applies not only to straight pipes and straight pipes, but also to various combinations such as straight pipes and irregularly shaped pipes, straight pipes and angled cut pipes, cut pipes and cut pipes, or irregularly shaped pipes.
The same applies.

As explained above, the tube holding device of the present invention can be used for butt welding of any combination of tubes, has a wide range of applications, and is highly accurate for correcting misalignment, maintaining proper gap, etc. Able to perform work. Furthermore, since the pressing bolt is provided with a loose cap, it is possible to follow the curvature of the pipe without leaving impressions on the pipe surface.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a clamp body constituting the present invention, Fig. 2 is a sectional view of the clamp body, Fig. 3 A and B are partial sectional views showing an example of a pressing bolt used in the present invention, and Fig. 4 I. , B are a top view and a side view showing a specific example of a means for connecting clamp bodies to each other, and FIG. 5 is an explanatory diagram illustrating a holding device of the present invention for joining a straight pipe and a deformed pipe. 1... Clamp body, 2... Notch, 3... Connector, 4
...Guide member, 5...Press bolt, 6...Button,
7... Loose cap, 8... Set screw, 9... Groove, 1
0...Protrusion, 11...Groove, 12...Flange, 13...
Hinge bolt, 14... recess, 15... tube.

Claims (1)

[Claims] 1. A means for connecting the clamp bodies to each other is provided at both ends of an arc-shaped clamp body having notches spaced apart in the circumferential direction of the central portion, and a plurality of guide members are provided at intervals on one side of the circumferential inner surface of the clamp body. In addition, at least two rows of press bolts are arranged in the clamp body that are movable in the radial direction and have a spherical tip surface at the tube side end, and the press bolts are arranged at the tube side end of each of these press bolts in a direction around the bolt axis. A pipe welding holding device characterized by being equipped with a loose cap that is rotatable and tiltable in any direction relative to the bolt axis.