JPS605366B2 - Mounting device for mandrel bar in plug mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mandrel bar mounting device in a plug mill.

The plug mill has upper and lower rolling rolls 1 and 2 with calibers, return rolls 3 and 4, and a guide mechanism 5 between the rolls in a mill body 6, and a mandrel lever is installed between the rolling rolls 1 and 2 of the mill body. A plug (cored metal) 9 supported by a mandrel anchor 8 via -7 is provided, and a front table 11 having a busher device 10 and a rear table 13 having a pipe guide mechanism 12 are provided at the front and rear of the mill body 6. The hollow shell A arranged and fed to the front table 11 is transferred to the pusher device 1
01, so that it is pushed into the mill main body 6 and rolled by rolling rolls 1, 2 and a plug 9 (see FIG. 1).

However, as mentioned above, the mandrel bar 7 in the conventional plug mill is attached to the mandrel anchor 8 arranged on the rear side of the plug mill rear table 13 by means such as bolting, and when replacing it, the fixing means must be removed. This is done by pulling it out forward through the mill body 6, that is, toward the front table.

Therefore, it is very difficult to attach and detach the mandrel bar, and the work requires a long time.

This invention was made in order to improve the above-mentioned conventional drawbacks, and its purpose is to provide a mandrel bar mounting device which allows the mandrel bar to be mounted easily and reliably, and which also allows the mandrel bar to be pulled out backwards. This is what we intend to provide.

Hereinafter, the structure of a mandrel bar mounting device according to an embodiment of the present invention will be explained with reference to the drawings in FIGS. 2 to 7.
An elliptical birch car passage horizontal hole 15 is inserted into the mandrel anchor 8 disposed on the rear side of 3 so that the mandrel bar 7 can be adjusted vertically and pulled out rearward.
A guide hole 18 having a tapered surface 17 into which the thrust receiving plate 16 is vertically movably inserted is formed. The thrust receiving plate 16, which is vertically movably inserted into this guide hole, has an inverted U-shaped notch 19 whose lower end is closed through which the up-end portion 7b of the mandrel bar 7 is inserted, and its front side surface 16a is a vertical surface. At the same time, the rear side surface 16b is formed as a tapered surface complementary to the tapered surface 17 of the guide hole 18. This thrust receiving plate 16 is normally pushed down via a mounting bar 20a by two cylinders 20 and 21 arranged obliquely on both sides of the mandrel anchor 8 as shown in FIGS. 2 and 3, and is a position-adjustable receiving plate. The lower end portion is in contact with and supported by the plate 22. The reason why the thrust receiving plate 16 is shaped like a sliding door and can be moved up and down along the guide hole tapered surface 17 is to adjust the mandrel bar 7 with a plug, which is supported by the thrust receiving plate 16, back and forth. By appropriately raising and lowering the thrust receiving plate 16 from the cylinders 20 and 211, and moving the receiving plate 22 with the worm jack 23 in accordance with the amount of movement, the forward and backward movement of the mandrel bar 7 can be adjusted. It will be done. The mandrel bar 7 has a rear end head portion 7a having a diameter larger than the cut groove width A of the thrust receiving plate 16, and an up end portion 7b having a small diameter that can be inserted into the receiving plate notch 19 protruding from the center of the head machine. , with this up end portion 7b inserted so as to protrude rearward of the mandrel anchor 8 through the notch 19 of the thrust receiving plate 16, the rear end head portion 7a of this mandrel bar 7 is vertically aligned with the thrust receiving plate 16. As shown in FIGS. 4A and 5, it is engaged and supported at both sides of the notch in the front side surface 16a. Reference numeral 24 denotes a clamp mechanism that clamps the mandrel bar 7 between it and the thrust receiving plate 16, and this is a clamp mechanism that has a hole 25 through which the mandrel bar 7 is inserted and comes into contact with the front end surface of the head portion 7a. 26, and both side extending arms 27, 28 of this press cylinder.
and the mandrel anchor 8.
It consists of clamp cylinders 29 and 30 that pull the vehicle rearward.

The press cylinder 26 of this clamp mechanism 24 is slidably guided by guide bodies 31 and 32 as shown in FIG.
5 is formed with a vertically long elliptical hole as shown in FIGS. 6 and 7, so that even when a mandrel bar 7 of any size is set at an appropriate vertical position in accordance with the rolling bus line of the plug mill,
The head portion 7a of the mandrel bar 7 can be reliably clamped with a pressing cylinder 26 for moving the stereotactic layer. A mandrel bar 7' shown by an imaginary line in FIG. 4 is a mandrel bar used when rolling a small-diameter pipe by lowering the rolling bus line. 33 is a vertically adjustable mandrel bar support that supports the mandrel bar 7 on a suitable rolling bath line, and this is vertically moved by lifting cylinders 34 and 35, and is moved up and down by a worm gear jack 36? It is mounted on a lifting beam 38 which is stopped at a predetermined raised position at 37 (see FIGS. 4 and 7).

The mandrel bar support 33 has approximately 120 mm at its upper end.
A V-shaped support surface 33a having an opening angle of 100 degrees is formed, and the head portion 7a with a circular cross section of the mandrel bar 7 is
As shown in the figure, it is supported from below. The tip of the mandrel bar 7 is supported at the front end of the plug mill rear table 13 by a guide roll 14 shown in FIG. In the case of a type in which rolling is carried out by raising and lowering the lower surfaces together, the guide roll 14 is pivotally attached to the tip of a rolling arm 39, as shown in FIGS. 8 and 9, and this rotating arm 39 is The axis 4
A fluid cylinder 4 connected to a lever 41 attached to the zero end
2 to perform roll escape when the rolled pipe a arrives, and also to attach the fluid pressure cylinder 42 to a worm gear jack 43 so that the operating position of the cylinder can be changed appropriately. , the upper limit rotation position of the guide roll 14 (mandrel bar 7
The guide position) is configured to be variable according to the top and bottom of the rolling bus line.

The device for attaching the mandrel bar 7 to the mandrel anchor 8 and the support mechanism for the tip side of the mandrel bar 7 have been described above, but here we will discuss the case where the mandrel bar 7 is removed. Loosen the valve, and raise the hydraulic cylinders 20 and 21 to pull up the thrust receiving plate 16 via the mounting bar 20a, and move the notch 19 upward from the up end portion 7b of the mandrel bar 7 as shown in FIG. 4B. By pulling it out, the rear end head portion 7a of the mandrel bar 7 and the thrust receiving plate 16 are disengaged.

A mandrel bar is attached to the flange (7c shown in FIG. 3) provided at the tip of this up-end portion 7b.
By hooking the towing tool of the exchange device (not shown) and pulling it backward, the mandrel bar 7 is attached to the mandrel anchor 8.
It is removed from the Since the mandrel bar mounting device of the present invention is as described above, the mandrel bar can be easily and reliably mounted to the mandrel anchor, and the mandrel bar can loosen the clamp mechanism and move the thrust receiving plate after the mandrel bar. The mandrel bar can be pulled out rearward with a simple operation of moving the end head to the engagement/disengagement position, and the mandrel bar can be replaced easily and quickly compared to the conventional front pulling operation.

Note that the thrust receiving plate 16 in the above embodiment is not limited to a sliding door shape, and may be a simple flat plate with a notch 19 that is open at the bottom end, or a notch that is closed at the top end. Alternatively, the thrust receiving plate 16 may be moved downward.

That is, in this embodiment, the thrust receiving plate 161 is provided with a U-shaped notch 19 whose upper end is open, and
By moving the thrust receiving plate 16 downward and disengaging the mandrel bar rear end head 7a, the mandrel bar 7 can be pulled backward, and its configuration is omitted in the drawing. However, by reversing the orientation of the thrust receiving plate 16 shown in FIG. It is said that the structure is reversed. Further, the mechanism for vertically movably supporting the mandrel bar 7 is not specified as a gist of the present invention, and is unnecessary when a conventionally known rolling bus line is applied to a certain plug mill.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram of a plug mill, Fig. 2 is a plan view showing an embodiment of the invention device in relation to the rear table;
Fig. 3 is a side view thereof, Fig. 4 is a longitudinal cross-sectional view of the mandrel bar mounting portion taken along line N-W in Fig. 2, and Fig. 4A is a relationship between the rear end head portion of the mandrel bar and the thrust receiving plate. FIG. 4B is an operation explanatory diagram showing a state in which the thrust receiving plate is engaged and disengaged from the rear end head portion of the mandrel bar; FIGS. 5 and 6; Figure 7 is V in Figure 4.
8 is a partially cutaway front view of the mandrel bar support mechanism at the front end position of the rear table, and FIG. 9 is a side view thereof. 7... Mandrel bar, 7a... Rear end head portion, 7b... Up end portion, 8... Mandrel anchor, 13... Rear table, 16...
... Thrust receiving plate, 19... Cut, 24.
...Mandrel bar clamp mechanism. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] 1 A roughly U-shaped cut with one end open in the width of the cut groove, which allows the rear end head portion of the mandrel bar to engage with the mandrel anchor placed on the rear side of the back table of the plug mill, and into which the up end portion of the mandrel bar can be inserted. A thrust receiving plate having a thrust receiving plate is provided so as to be movable from a position where it engages with the rear end head of the mandrel bar to a position where the notch in the receiving plate engages and disengages from the head, and the notches on the front face of the thrust receiving plate are located at both sides. The rear end head of the mandrel bar is engaged with the mandrel bar, and the up end of the mandrel bar is made to protrude rearward of the mandrel anchor through the notch in the thrust receiving plate, and the rear end head of the mandrel bar is thrust into the mandrel anchor. A plug mill characterized in that a clamping mechanism is provided between the mandrel bar and the receiving plate, and the mandrel bar can be pulled out rearward by loosening the clamping mechanism and moving the thrust receiving plate to an engagement and disengagement position. Mandrel bar mounting device.