JPH0641002B2 - Method and apparatus for producing pipes in a cold rolling mill - Google Patents

Abstract

1. Method for the production of pipes in a discontinuously operated cold pilger rolling mill (1), in which the billet (3) is drawn over a fixed mandrel rod (9) by means of grooved rolls rolling back and forth down on the billet (3), whilst the billet (3) is held by a feed slide (4) and is conveyed in the rolling direction by means of feed screws (6), and which has a rotatable mandrel support (8) on the run-in side, in which the mandrel rod (8) can be firmly clamped, and which can be opened to introduce the billet (3) into the cold pilger rolling mill (1), characterized in that for the rolling of billets (3) the length of which is greater than the effective length of the feed screws (6), the mandrel support (8) is moved toward the input side of the cold pilger rolling mill (1) by a multiple of this effective length of the feed screws (6) and that the feed slide (4) takes hold of the billet (3) and releases it respectively several times and repeatedly transports it further over a part of its length, the feed slide (4) being detached from the billet (3) after each conveying passage and returned to its initial position.

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a feed slide holds a raw pipe, and a feed spindle moves the raw pipe in the rolling direction, and a caliber roll that rolls back and forth on the raw pipe is used to fix the raw pipe. It is designed to stretch and process the raw pipe on the mandrel.It functions to hold the mandrel rod, but it has a rotary mandrel support that can be opened when supplying the raw pipe to the rolling mill. The present invention relates to a method for producing a pipe in an intermittent operation cold Pilger rolling mill and an apparatus for carrying out the method.

Cold rolling mills of the type described above, which are configured to insert a blank tube through a mandrel support opened from the inlet side, are also called rear loaders. This type of rolling apparatus is provided with only a mandrel support and a feed slide, which feed slide is designed to feed the rolled material by a fixed amount over a fixed distance, usually two feed spindles. Therefore, the maximum length of the blank used is exactly equal to the full travel length of the feed slide. This means that the feed spindle or its threading area is equal to the maximum tube length.

In the conventionally known cold rolling apparatus, since the effective length of the feed spindle is limited to about 15 meters for manufacturing reasons, the maximum length of the raw pipe that can be rolled is predetermined. Therefore, the length of the raw pipe that can be used is likewise determined to be approximately 15 meters, so that the throughput of the known cold rolling apparatus is limited by the maximum weight of the raw pipe. This is a disadvantage. This is because pipe manufacturers, especially copper pipe manufacturers, are required to roll more weight than conventional pipes, and it is necessary to use pipes larger than conventional pipes. This is because the above-mentioned cold Pilger rolling mill cannot meet this requirement.

Therefore, the object of the present invention is to use the components used in the cold pilger rolling machine of the type mentioned at the beginning as they are, and to perform the above-mentioned rolling in the rolling process of the raw pipe longer than the maximum effective length of the feed spindle. To be able to use the device.

In order to achieve the above-mentioned purpose, the feed slide is designed to grip the tube many times and transfer it by a part of its length over a number of times, and feed it from the tube after each transfer stroke. It was proposed according to the invention to release the slide and return it to its original position. According to the proposal of the present invention, it is possible to roll an extremely long raw pipe in a plurality of steps. The reason is that the length of the spindle is no longer a criterion for limiting the length of the raw pipe since the raw pipe is gripped many times.

The device for carrying out the method of the invention comprises a feed slide, which is already used in the case of a continuous operation cold Pilger mill, with a fixed chuck which grips around the pipe tube and a mandrel support with a rear feed. It is preferably arranged at a predetermined distance from the end of the spindle and is arranged such that this distance is set to a multiple of the maximum feed length of the feed slide. Since the circumference of the raw pipe is gripped, the gripping operation can be performed any number of times, so theoretically, the raw pipe can be designed to have any length. According to the proposal of the present invention, a raw pipe having a length of 25 to 30 meters can be directly fed to the rolling mill depending on the distance between the mandrel support and the end of the rear feed spindle.

When a new raw tube is fed into the rolling apparatus when the rolling apparatus is stopped or while the rolling apparatus is operating, the feed slide is returned to re-grip the raw tube.

INDUSTRIAL APPLICABILITY The present invention can meet the requirement of rolling an extremely large raw pipe by using a simple structure. The loading time and the feed slide return time calculated as a percentage based on the rolling time of the raw pipe are more advantageous than in the case of known rolling mills of this type, in which the maximum length of the raw pipe does not exceed 15 meters. .

Furthermore, according to the invention, it is proposed to provide the rear feed transmission between a mandrel support and a fixed tube guide and a tube bed with a mandrel guide, which of this component The structure is characterized by being very simple. A slight change in the rolling apparatus while using the components that have been used in the past can bring about a remarkable effect and can significantly increase the productivity.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings illustrating an embodiment of the present invention.

A rolling stand of a cold Pilger mill which is adapted to be driven in a manner known per se using a feed crank drive with a counterweight 2 is designated by the reference numeral 1 in FIG. A feed slide 4 is provided to feed the raw pipe 3 to be rolled, and the feed saddle 4 is provided.
Is adapted to grip the rear end of the raw pipe 3 and feed the raw pipe 3 to the rolling device 1 in the direction of the arrow indicated by reference numeral 5. The feed slide 4 is driven by means of a spindle 6 which is provided with a rotary movement through a transmission 7.

The mandrel support which grips the mandrel rod at the end remote from the rolling mill is designated by the reference numeral 8. The mandrel support 8 can now be opened so that a new tube can be inserted through the mandrel support 8. The length of the raw pipe that can be used in the conventionally used cold Pilger rolling mill as shown in the embodiment is determined by the length of the feed spindle 6 in the feed stroke of the feed slide 4. It is decided based on it. Due to manufacturing reasons, the length of the feed spindle 6 is limited to about 15 meters, so that this length corresponds to the feed stroke of the feed slide 4 between the transmission 7 and the rolling stand 1. Become.

Thus, the cold rolling apparatus according to the present invention is shown in FIG. 2, and the same components as in FIG. 1 are designated by the same reference numerals. The difference from the prior art cold rolling apparatus shown in FIG. 1 is that in the cold rolling apparatus according to the present invention, the mandrel support 8 is moved a considerable distance toward the inlet side. I can mention that. Nevertheless, the distance traveled by the feed slide 4 determined by the length of the feed spindle 6 remains the same, but as shown by reference numeral 9, a significantly longer mandrel rod is used. Has been done.
The length of the feed spindle is no longer the criterion for determining the tube length, since the feed slide 4 is adapted to grip the tube many times to provide feed. The length of the blank tube can be at least as large as the distance between the inlet of the rolling mill 1 and the mandrel support.

The element pipe bed, which is arranged between the rear transmission device 7 and the mandrel support 8 indicated by the reference numeral 10, is provided with a fixed element pipe guide and a mandrel guide 11. Very easy. It can be easily understood from FIG. 2 that the same components as those used in the prior art are used except for the pipe tube 10. According to the proposal of the present invention, the feed slide 4 grips the raw pipe 3 many times and guides the raw pipe 3 by a predetermined feed distance in the direction of the arrow indicated by the reference numeral 5. , The production efficiency can be greatly increased with a small cost. In the present invention, the open rear mandrel support 8 is used to move the tube 3 in the usual manner.
The length of the blank tube can be made significantly longer than that in the prior art shown in FIG.

[Brief description of drawings]

FIG. 1 is a side view of a cold rolling apparatus configured according to the prior art. FIG. 2 is a side view of a cold rolling apparatus configured according to the present invention. 1 ... Rolling stand, 2 ... Counterweight, 3 ... Element tube, 4 ... Feed slide, 5 ... Feed direction, 6 ... Spindle, 7 ... Transmission, 8 ... Mandrel support , 9 …… mandrel rod, 10 …… blank tube bed, 11 …… blank tube guide.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Joseph Gerets, Federal Republic of Germany De-4060 Fehlsen 12 Lortsingshüttraße 4 (72) Inventor, Fritz Tuinert De-4050 Mengengla, Germany Tobatsuka 2 Am Haag 2 (56) References JP-A-47-33854 (JP, A) JP-A-53-149160 (JP, A)

Claims (3)

[Claims] 1. A feed slide holds a raw pipe, and a single feed spindle moves the raw pipe in the rolling direction, while using a caliber roll that rolls back and forth on the raw pipe, the raw slide is fixed on a fixed mandrel. Intermittent operation with a rotating mandrel support on the inlet side that is designed to stretch the pipe and acts to grip the mandrel rod, but can be opened when supplying the raw pipe to the rolling mill. The method of manufacturing pipes with the cold pilger rolling machine of No. 1, in which the feed slide grips the raw pipe many times and transfers the raw pipe over a part of its length many times. After that, the feed slide is released from the tube and returned to its original position. 2. A feed slide holds a raw pipe, and a single feed spindle moves the raw pipe in the rolling direction, while using a caliber roll that rolls back and forth on the raw pipe, the raw slide is fixed on a mandrel. Intermittent operation with a rotating mandrel support on the inlet side that is designed to stretch the pipe and acts to grip the mandrel rod, but can be opened when supplying the raw pipe to the rolling mill. Cold pilger mill with a feed slide having a fixed chuck that grips around the pipe tube, and a mandrel support located at a distance from the rear feed spindle end. The device is characterized in that this distance is set to a multiple of the maximum feed length of the feed slide. 3. The apparatus according to claim (2), wherein a blank tube bed having a fixed blank tube guide and a mandrel guide comprises a rear feed spindle transmission and a mandrel support. An apparatus characterized by being provided between.