JPS6324961Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention eliminates the need to change the attachment of the rack that operates the mandrel even if the size of the mandrel used when manufacturing seamless pipes with a mandrel mill changes, speeding up the rolling operation. The present invention relates to a locking device for a seamless pipe manufacturing mandrel.

When manufacturing seamless pipes using the mandrel mill method, the mandrel is passed through a shell with holes made with a punching machine and rolled with caliber rolls.
Since it is necessary to also move the mandrel in the direction of movement of the shell, a rack-type feeding device has conventionally been used.

On the other hand, depending on the inner diameter of the seamless pipe, the mandrel needs to be replaced, but if the mandrel is replaced, the attachment for pushing and pulling the mandrel attached to the rack must also be replaced, and this replacement takes time. This caused problems such as reduced work efficiency and dangerous replacement work.

The purpose of this invention is to eliminate dangerous work by eliminating the need to replace the rack attachment even if the mandrel is replaced, and to speed up rolling work. A plurality of locking portions are provided at the tip of the rack to be moved to, so that the rack is large on the tip side and becomes smaller as it moves away from the tip so as to be able to lock with the collar of the mandrel. .

Hereinafter, embodiments of the present invention will be described based on the drawings.

A guide wheel 3 that can roll along a rail 2 is pivotally attached to the side of a rack 1 extending in the longitudinal direction of the shell, and a pinion 4 that can be rotated by a drive device (not shown) is meshed with the rack 1. A plurality of locking portions 7a, 7 are provided for at least allowing the rack 1 to move in the longitudinal direction of the shell and for pushing the mandrel 6 against the attachment 5 attached to the tip of the rack 1.
b, 7c are provided. The locking portions 7a, 7b, and 7c have different dimensions, and are provided corresponding to the type of mandrel. That is, the flange portion of the mandrel 6 has a size corresponding to the diameter of the mandrel 6,
Therefore, the largest shaft 6 is placed on the tip side of the attachment 5.
A locking portion 7c is formed with which the collar portion engages.
In addition, locking portions 7b and 7a are sequentially formed as the distance from the tip increases, and the mandrel 6 with a smaller diameter engages with its collar. It is designed to support.

During rolling, a mandrel 6 with a plug attached to the tip
is lowered by a cylinder or the like, the collar is locked in a predetermined locking part of the locking parts 7a, 7b, 7c of the rack 1, the pinion 4 is driven to move the rack 1 forward, and the mandrel 6 is moved forward. Rolling is performed using a mandrel mill while pressing. If the mandrel is changed, it is necessary to change the locking part where the collar part is locked. For example, if the mandrel is the smallest, use the locking part 7a as shown in Figure 1, and if the mandrel is in the middle, use the locking part 7a as shown in Figure 3. The locking portion 7b is used, and in the maximum case, the locking portion 7c is used.

Although the embodiment of the present invention has been described with reference to the case where the rack locking portions are provided at three locations, it is possible to use any number of locations as long as there are multiple locations, and various other changes may be made within the scope of the gist of the present invention. Of course, etc.

Since the locking device of the seamless pipe manufacturing body rod of the present invention has the above-mentioned configuration, there is no need to replace the attachment for pushing the mandrel even if the size of the mandrel changes, so there is no downtime on the line due to replacement. Therefore, various excellent effects can be achieved, such as improved rolling efficiency and no danger associated with replacement.

[Brief explanation of the drawing]

FIG. 1 is a side view of the present invention, FIG. 2 is a plan view of FIG. 1, and FIGS. 3 and 4 are illustrations of how to use the present invention. In the figure, 1 is a rack, 4 is a pinion, 5 is an attachment, 6 is a shaft, and 7a, 7b, and 7c are locking parts.

Claims (1)

[Scope of utility model registration request] A moving device for moving the mandrel in the longitudinal direction is provided with a plurality of locking parts at the distal end thereof, which are large on the distal end side and become smaller as they move away from the distal end so as to be able to engage with the collar of the mandrel. A locking device for a seamless pipe manufacturing bodyguard.