DE801029C - Process for actuating the workpiece pre-fetching device of pilger step rolling mills - Google Patents

Description

Method for actuating the workpiece advance device of pilgrim step rolling mills I) an economic operation of l'ilgersclii-itt @ \ - alz- i \ Erkell requires rapid training of the bc- away. Masses (workpiece, pilgrim thorn, thorn lock and \ 'orholgestänge with Vorholz cylinder piston) and their substance-free braking over a short braking distance. ran <leli geliräuchlicheu \ -oi-liolvorrichttingen is the \ 'orliolzvlinder on the kelirtell side (drive side) with compressed air correct pressing g (, fills. Home start of rolling \ organges is the lZÜcl: blow @ -valve of the I) return air- ztileittiiig gesclil @ isscll. \\: at the end of the rolling process the \ -lirllolz @ -lin <lei-kollien over the gcst: inge <ltil-cli the key force between rollers and the workpiece is moved in rolling motion. Through this the pressure enclosed in the cylinder frame air atif li # Aiere pressing \ -deals. As soon as that The workpiece leaves the roller. begins that brake the moving 1 \ let through the compressed Compressed air, which is in the rear dead center position of the Piston is finished. The subsequent catch-up movement of the masses in the direction of the rolling work is done by relaxing the compressed Compressed air. To slow down the hate up to the the front dead center position is a usual water brenise. The pre-haul device described ran kaim <1e r pressure of the pressure- ltift only up to a certain limit value increases «-erden through the frictional force between the rollers and the workpiece. If this limit is exceeded, occurs a carriage between rollers and '' workpiece. , # vo <kircli the upper surface of the workpiece is damaged. Panlit also limits the salt speed, which essentially depends on the amount of pressure in the \ 'orholzylinder.

According to the invention, the rolling speed is increased in that the Pre-wood cylinder on the drive side, alternating compressed air from two different ones Pressure levels is supplied, with the low pressure level during the salting process "rirl glue decelerates the advance movement d: e high l) jerk when decelerating the Reverse and during the first part of the advance movement.

It is known,) 'Orholvorrichtungen from pilgrim step rolling mills with To operate compressed air from two different pressures, the lower Pressure level on the one facing the rolling mill, the higher pressure level on the opposite side of the piston acts. The pressure difference provides the advance force. The pressures of Compressed air supplied on both sides of the piston are independent of one another adjustable, but they remain the same during a rolling, and their change is only aimed for when changing the rolling program (patent specification 361.123).

The illustration shows, for example, the pressure curve in the pre-wood cylinder during a pilger rolling process when using the method according to the invention in the form of a path-pressure diagram. In the diagram, s mean the total piston travel, s1 the path of the air piston during the rolling process from the front dead center position i until the rolling stock is released by the rollers, point 2, s2 the braking distance of the Air piston up to the rear dead center position 3, s3 the advance travel over points 4 and 5 to point 6, s1 the braking distance to the front dead center position i. p1 is the low pressure stage, p2 the high pressure stage.

During the rolling process (path s1) the compressed air acts as usual low pressure p1 on the drive side of the air piston. As soon as the rolling stock has left the rolling pass, the low pressure p1 is switched off and the high pressure line opened. From point 2 onwards, compressed air flows with the pressure p2 on the braking distance s2 one that lies above the previously achievable compression. This makes a faster one Braking until the rear dead center position is reached (point 3) and then brought about an accelerated forward movement. If the forewood cylinder has a sufficient The high pressure supply line is filled with compressed air of the higher pressure level p2 closed and the air piston by releasing the enclosed compressed air in Driven on towards the roll stand. Shortly before the end of the relaxation the diamond cylinder is reconnected to the low-pressure network (point 5) and the pressure in the cylinder drops rapidly to p1. At point 6 is the outflow of the compressed air higher pressure mainly ended; here the _ ", hl) reinsen the advance movement by means of the water pressure fluid on the path s1. In the front dead center position i starts a new workflow.

The compressed air is controlled in a manner known per se. The two pressure levels can be regulated independently of one another. Instead of compressed air other propellants can also be used.

The application of high pressure compressed air according to the invention causes a substantial increase in the rolling speed and thus an increase in the Rolling mill production. By constantly repeating new supplies and relaxing the compressed air is cooled by the air cylinder and when compressed air is used Heating occurring in the closed cylinder space according to the previously customary process the cylinder walls, the heavy wear of the seals and high cooling water consumption has the consequence turned off.

Claims (1)

PATENT CLAIM: Method for actuating the workpiece advance device of pilgrim step rolling mills, with the blowing agent of two different pressure levels are used in the Vorholzylinder, characterized in that the propellant high pressure to slow down the return and to advance, the propellant lower Pressure, on the other hand, during the braking of the advance movement and during the salting process is fed.