DE2229320A1 - DRIVE FOR STRETCH-REDUCING ROLLER MILLS - Google Patents

Description

Berlin, June 13, 1972 M / room

Mannesmann-Meer Aktiengesellschaft, 405 Mönchengladbach, Ohler Kirchweg 66.

M 653 - drive for stretch-reducing mills

As is well known, in addition to a reduction in the outside diameter of the pipe, the stretch reducing mill is also used achieved a reduction in wall thickness; the latter is achieved in that each between the stands a longitudinal pull is exerted on the pipe by the rolling speed from stand to stand is increased so that the tensile stresses are as uniform as possible the desired reduction is present.

The following drive systems are common in stretch-reducing mills:

1. Rigid drive from a motor, which is connected to the scaffolding via a longitudinal shaft through bevel gears is connected (DBP 9ol 526) j here, however, only a certain reduction in diameter and wall thickness can be achieved take place under favorable conditions;

2. Rigid drive with overlay that can be set jointly for all scaffolding, with the scaffolding from a motor driven at constant speed and between bevel gears and stands each a differential gear is provided and the housing of this gear with a motor

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are connected, the speed of which can be regulated (DBP 976 3o8); the scope of this However, the rolling mill is limited by the fact that the speed range is unfavorable when the tube reduction is changed will;

3. Drive of each stand by its own superimposed drive that is independent of the other stands, whereby the speed of the rolls of each stand can be changed individually and continuously (DAS 1 293 llo); here can the The superimpositions are also driven by the main drive via hydraulic pumps and motors (DBP 97o Io2). Another possibility for individual drive of the scaffolding is through controllable Single electric motors given (Gbm 7 oo7 717).

The advantage of the last-mentioned individual drives lies in the favorable adjustability of the course of the tension for each reduction program; its disadvantage lies in the high effort involved with these connected is.

In order to limit this effort, the adjustable individual drive was installed on some of the scaffolding The beginning and end of the machine are restricted (DBP 932 663).

This simplification was paid for by the fact that stretch-reducing mills of this type were in use only to a very limited group of pipes, for example gas and water pipes according to DIN 224oo are restricted.

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The invention is therefore based on the object to create a drive in which, despite saving on control units in a large area Pipes can be reduced without significant deviations from the techno— ' logically most favorable speed range ".

To solve this problem it is proposed according to the invention that several adjacent Scaffolds are combined into a group, each group having a transfer case, irvflem the outputs through fixed lower or gear ratios are connected to each other and for each transfer case one with continuously variable Motor-connected input is provided.

On the basis of the attached drawing, which shows a top view of a stretch-reducing mill with shows the drive according to the invention in a schematic representation, an embodiment of the Invention explained in more detail.

In the illustrated embodiment, the continuously variable drive motors 1, the Electric motors, hydraulic motors or summation gears can be, via clutches 2, the input shafts the transfer case 3 is driven, each of which in the illustrated embodiment three output shafts to the stand drives 5 of the stretch reducing mill 4 go off.

The gear wheel connections between the scaffolding

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drove 5 each transfer case 3 are dimensioned so that in the context of the in question Reduction programs, the deviations from the optimal speed ratios are only slight and fully meet the practical requirements.

On the other hand, by reducing the control points to a fraction of those for individual drives required number in the type of drive according to the invention, significant cost savings possible.

- Claim -

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Claims (1)

Claim: Drive for stretch-reducing mills by means of individually controllable drive motors characterized, that in each case several neighboring scaffolds are combined into a group, each Group has a transfer case, in which the outputs by fixed lower or gear ratios are connected to each other and for each transfer case one with continuously variable Motor-connected input is provided. Dipl.-In 309881/0228 Blank page