JPS5914002Y2 - Plug-engaging mandrel bar - Google Patents

Description

[Detailed description of the invention] This invention relates to the creation of a method for attaching and removing plugs in inclined rolling mills for seamless steel pipes such as boring machines, elongators, reelers, etc., and provides plugs that allow plug replacement operations to be performed simply and reliably. This invention relates to an engaging mandrel bar.

As recent plug-engaging mandrel bars, the systems shown in FIGS. 1, 2, and 3, and the system shown in FIG. 4 are known.

The method shown in Figures 1, 2, and 3 attaches and detaches the plug near the end of the range of movement of the mandrel bar.To explain this plug-engaging mandrel bar with a diagram, 2 is the plug and the inside of the plug is consists of a hole 8 and an annular groove 10.

Reference numeral 4 denotes a mandrel bar, and a tip metal fitting 3 is screwed to the tip of the mandrel bar.

An elastic thin plate 12a made of spring steel is attached to this end fitting.
12b is fixed with a bolt 13 so as not to move.

Further, a spring plate 16 is provided inside this elastic thin plate, and a hook claw 11a.

11b is used to add restoring force.

In order to prevent the claw of this hook from opening too much, a collar 17 is secured to the tip metal fitting 3 with a bolt 18.

To attach the plug 2 to the end fitting 3, insert the end fitting 3, which is located at the position of the imaginary line, into the hole 7b of the container, and insert the plug 2 housed in the hole 7 of the container 6 shown in FIG. By pressing the protrusions 5a and 5b, the hook claws 11a and 11b are contracted as shown by the imaginary lines in FIG.
Insert the plug into the inner hole 10.

Then, by further pushing out the bar, 5a, 5b
When the plug reaches the hole 7, the hook claw clamps the plug 2 by the action of the spring.

Thereafter, the mandrel bar 4 is moved to advance the plug to the position of the roll, and rolling is performed.

When rolling is completed, the shell 1 is stopped by a container 6 placed at the rear of the rolling mill.

The plug 2 then passes through the shell and stops at a stopper inside the container.

At this time, the protrusions 5a and 5b of the elastic thin plate are also pressed by the hole 7b, and the hook claw is in a state as shown by the imaginary line in FIG. 1, so that the plug can be easily released.

This plug-engaging mandrel bar is designed to ensure reliable clamping by making the wall of the groove 10 of the plug hole and the claws 11a, 11b of the hook vertical.

Also, by pressing the protrusions 5a and 5b with a container, the plug can be attached and detached from the tip fitting.

This plug-engaging mandrel bar is difficult and expensive to manufacture because it requires a complicated container to be replaced depending on the type of mandrel bar, and the hook claw body made of spring steel has a complicated shape.

Furthermore, since the hook claws are only provided at two locations on the circumference, the plug lamp becomes unstable and its strength is weak.

Further, even when replacing one hook pawl, it is necessary to remove bolts 13 and 4 stud bolts 18, resulting in a disadvantage that it takes a long time for replacement.

On the other hand, the method shown in Fig. 4 is used when the plug is passed through the shell together with the mandrel bar when the shell is sent to the next process after rolling is completed. The interior of the plug consists of a cavity 19d and a hole 19a on the inlet side of the stepped portion 1000.

21 is fixed to the mandrel bar '20 with an adapter.

A link 23 has a stopper 238 and is rotatably screwed to the adapter 21 with a pin 24.

Reference numeral 25 denotes a spring device that constantly exerts a force on the link 23 in the direction of the axis.

22a is fixed to the water pipe 22 by a cam device, and a device such as a cylinder at the rear end of the mandrel bar moves the wood pipe in and out to raise or sink the stopper 23a of the link.

These links are provided at several locations on the circumference.

When clamping the plug, connect the cam device 22a to the water pipe 2
Pull backwards through 2.

As a result, the link 23 is rotated toward the axis by the spring device 25 using the pin 24 as a fulcrum.

As a result, the stopper 23a is attached to the adapter tip 21.
It sinks closer to the axis than a.

In this state, insert the tip of the adapter into the plug end face 1.
9 Insert until it stops at b.

Thereafter, by pushing out the cam device 22a, the stopper 23a floats into the space 19d inside the plug, thereby clamping the plug.

To remove the plug, pull the cam device to sink the link stopper and pull out the adapter tip from the inside of the plug.

In this way, the plug is attached to and removed from the tip of the adapter.

Since the conoplug engaging mandrel bar clamps the plug with the link stopper via the cam device, the plug clamping is reliable and strong.

However, since a cylinder device for inserting and removing the cam device is required at the rear end of the mandrel bar, the mechanism is complicated and expensive.

Therefore, this idea has a simple structure, can be manufactured at low cost, has sufficient strength, allows for reliable installation and removal of plugs, is long-lasting, and enables stable automatic plug replacement. It is an object of the present invention to provide a plug-retaining mandrel bar.

With the plug-engaging mandrel bar of the present invention, the plug is removed in front of the shell without the plug passing through the shell after rolling, only the mandrel bar passes through the shell, and the shell is sent to the next process. .

used in such cases.

This design does not require the plug to pass through the shell after rolling, so compared to the methods shown in Figures 1 to 4, the inner surface of the shell is not damaged by the plug, and it is advantageous in terms of plug wear. It is.

Further, the clamping force of the plug does not need to be so strong, and the mechanism of the present invention, which will be described below, can be used in which the hook is sunk and the plug is removed by forcibly pulling the plug apart.

To explain an embodiment of the present invention with the help of drawings, the general relationship of the plug replacement work in an inclined rolling mill etc. is as shown in FIG. A shell fed from the direction of the arrow on the input table is rolled by rolls 26, 26 and a plug 27 at the position shown by the imaginary line, and after the rolling is completed, the plug retreats to the position shown by the solid line 27.

At this time, the shell 31 is also sent to the position shown in the figure by the roller table.

After that, insert the plug stopper 30 with a U-shaped notch into the sixth
The plug 27 is removed from the plug-engaging alloy 29 by covering it as shown in the figure and retracting the mandrel bar 28.

At this time, the plug-engaging alloy 29 of the present invention is fixed to the mandrel bar 28 with screws 35, as shown in FIG.

The plug 27 is provided with a stepped portion 32 at a position close to the inlet portion.

This stepped portion 32 may be formed as an inclined wall, but if it is inclined too much, the engagement will be insufficient.

Reference numeral 36 denotes a hook for plug clamping, which is rotatably attached to the plug-related alloy 29 at several locations on the circumference by means of pins 37 at the midpoint of its handle.

By tightening the coil spring 38 with a spring holding bolt 39, the tip of the hook 36 is moved away from the axis.

It is also necessary that the base 36' of the hook 36 be a gently sloping wall.

Attachment/removal to/from the plug 27 is accomplished by inserting the distal end 40 of the plug-engaging alloy 29 into the inlet hole 33 of the plug 27, which is formed into a conical shape to facilitate advancement and withdrawal into the plug inner cavity 32. Hook 36 is pushed by the inner surface of 33, and pin 3
7 as the center of rotation and sinks into the groove 41 as shown by the dotted line.

At this time, the spring 38 is compressed by compressive force.

When the insertion is completed and the head of the hook reaches the plug stepped portion 32, the hook 36 is lifted up by the spring action of the coil spring 38 and returns to its original position.

This completes the clamping of the plug.

To remove the plug, place a piece of metal with a U-shaped notch 30 over the plug engaging fitting 29, and move the mandrel bar backward to press the hook 36 against the inner surface of the plug 34, and the vertical component forces the hook 36. By sinking the plug into the groove 41 at the position indicated by the dotted line, the tip of the plug-engaging alloy can be easily removed.

That is, by adopting this structure, the shape of the hook becomes very simple compared to those shown in FIGS. 1 to 3, which makes it easy to manufacture and requires no spring properties, so it can be manufactured at low cost.

In addition, the hooks can be made sufficiently strong within the space allowed, so there is no accident of breakage during use, and there is no need to stop rolling due to breakage.

In addition, since a simple coil spring can be used as a spring, you can choose one that is heat resistant, which eliminates the possibility of spring fatigue due to temperature and greatly extends the lifespan.

Parts such as the hook can also be replaced by loosening and removing the threaded portions of the pin 37 and the spring holding bolt 39 without removing the screws at the connecting portion with the mandrel bar.

Compared to the one shown in Fig. 4, it has a simple structure and can be manufactured at low cost because it does not have a cam device, a water pipe, or a cylinder device for taking in and out wood pipes.

In addition, there are great advantages in that the plug can be quickly and reliably installed and removed, and can be used for a long time.This enables stable automatic plug replacement, which can greatly contribute to increased production.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional side view showing an example of a conventional plug connection part, and Fig. 2 is a view of the end of the metal fitting fixed to the mandrel bar end fitting in the mandrel bar of Fig. 1 without movement. Plug has been removed. FIG. 3 is a longitudinal sectional side view of a portion of the mandrel bar shown in FIG. 1 where the plug is attached and removed. FIG. 4 is a longitudinal sectional side view showing another example of the plug connection portion. FIG. 5 is an overall relational diagram of the plug replacement work of the present invention, and FIG. 6 is a sectional view taken along the line AA in FIG. 5. FIG. 7 is a longitudinal sectional side view of the plug connection part in the embodiment of the present invention. 1...Shell (raw pipe), 2...Plug, 3...Tip fitting, 4...Mandrel bar-15a, 5b... Elastic protrusion, 6...
... Container, 7, 7 a, 7 b ... Container hole, 8 ... Space, 9 ... Tip of end fitting,
10... Annular groove, lla, 11b...
・Hook claw, 12a, 12b...elastic thin plate, 13...por), 14a, 14b...
...Vertical part of the hook claw, 15a, 15b...
Vertical portion of annular groove, 16...Spring plate, 17...
...Brim, 18...Shut bolt, 19.
...Plug, 19 a ... Plug entry hole, 19 b ... Plug end surface, 19C ...
・Plug stepped part, 19d...Plug empty space, 20
...... Mandrel bar 121... Attachter, 21a... Adapter tip, 22...
...Water pipe, 22 a...Cam device, 23...
...Link, 23a...Stopper, 24...
...Pin, 25 ...Spring device, 26
...Roll, 27...Plug, 28.
... Mandrel bar 129 ... Plug engagement fitting, 30 ... Plug stopper, 31 ...
...Shell, 32...Plug stepped part, 33
...Plug inlet side hole, 34 ...Plug inner wall, 35 ...Screw, 36 ...Hook, 37 ...Pin, 38 ......Coil spring, 39...Coil pressing bolt, 40...
...Tip of tip metal fitting, 41...groove.

Claims (1)

[Scope of utility model registration request] A plug-related alloy having a cone-shaped tip that can move forward and backward into the plug bore, and the other end of which is detachably joined to a mandrel bar, which has a hook entrance/exit window in the middle of the conical tip; A lumen connected to the window is provided, and a hook portion having an inclined base in the lumen is located at the entrance/exit window, and is pinned to the wall of the plug-engaging alloy lumen at a midpoint of the handle, Furthermore, a plug engagement mandrel bar 0 in which the handle end is engaged with an engagement metal wall via a repulsion spring.