SU984398A3 - Pilger mill for cold-rolling of tubes - Google Patents

Abstract

Cold pilger mill uses a reciprocating roll stand with a main drive and two feeder slides each fitted with a clamping chuck and arranged along the rolling line. Each slide is driven along a slideway via a threaded spindle actuated by a set of gears. One retractable mandrel support (RMS) is located between the two slides; and a second RMS is located at the back end of the mandrel. Each set of gears can be independently connected to the drive but, when not coupled to the drive, each has a motor for high speed movement of the slides. The mill can be used as either a continuous or discontinuous tube rolling mill, i.e. it possess the advantages of both types so tubes of any length can be rolled.

Description

The invention relates to pipe rolling production, namely to a pilger mill for cold rolling pipes with a movable working stand.

Known ho- pilger mill for rolling pipes ⁵ lodnoy batch comprising a working cage driven reciprocating movement, feeding mechanism with two screws and cooperating with them the carriage carrying the workpiece holder £ 1}.

In this mill for the period of installation of a new pipe billet, the mill must be stopped. The stopping time, even during automation of the workpiece installation process, depending on its length, cannot be less than 3560 s. A disadvantage of batch mills is that, with short workpiece lengths and small feed rates, mill downtimes increase, resulting in lower mill productivity.

Known pilger mill for ho- _{May 2} lodnoy rolling tube, significantly reducing downtime by continuity of the mill work comprising a working cage, drive its reciprocating movement from the main motor, two coaxial workpiece chuck, their feed screws mechanisms WHO VRÁTNA-translation and rotation of the feed screws associated with the main engine, two rod clamps sequentially arranged one after another, one of them being placed behind the second workpiece cartridge.

The distance between the clamps of the rod is such that when installing a new tube billet, it decreases between these clamps £ 2].

The drawback of pilger mills for cold rolling of continuous pipes is that they can operate in continuous mode only if billets are available for this continuous mode, the length of which exceeds the minimum length of the tube billet necessary for the continuous operation of the pilger rolling mill. This minimum length of the workpiece is significantly greater than the minimum length of the workpiece for rolling a batch mill. The well-known continuous mill does not allow rolling blanks of various lengths without lowering productivity and rolling pipes on the same mill both continuously and intermittently.

The aim of the invention is to increase the productivity of the mill. 5

This goal is achieved by the fact that in a pilger mill for cold rolling of pipes containing a working stand, its drive is reciprocating movement from the main 10 engine, two coaxially arranged workpiece chucks, their feed screws, reciprocating mechanisms and rotation of the feed screws are connected with the main engine 15, two clamps of the rod, one of which is located behind the second boss of the workpiece, the mechanisms of reciprocating movement and rotation for each screw are made independent and 20 a second rod clamp is located between the workpiece cartridges.

The proposed mill allows you to roll pipes of various lengths, which 25 leads to an increase in its productivity.

In FIG. 1 shows a mill in continuous operation, general view, 'in FIG. 2 - the same, with periodic, θ com operation mode) in FIG. 3 - schematic arrangement of the mechanisms for moving and rotating the screws and clamps of the rod in the mill.

The pilger mill for cold rolling of pipes contains a working stand 1 with rolls 2, a drive for its reciprocating movement in the form of a main engine 3, a belt drive 4 and a connecting rod 5, a device for balancing the moving masses of stand 40 in the form of loads 6 and 7. For feeding the tube stock the rolls are provided with two coaxially arranged chucks 8 and 9 of the workpiece with nuts 10 and 11 fixed inside them and individual feed screws 12 and 13 interacting with the latter. Each feed screw has independent mechanisms for its reciprocating movement and rotation associated with the main 5Q engine 3.

To drive the reciprocating movement of the feed screw 12, a cam lever 14 is used, connected to the main engine through gear 15 and the clutch 16, and for the feed screw 13, a similar mechanism 17 is connected to the main motor via gear 15.

For rotation of the feed screws 60, independent mechanisms 18 and 19 are also provided, which are respectively connected by high-speed operation engines 20 and 21 through clutches 22 and 23, as well as through transmission 65 with the main engine. For rolling the workpiece 24 using a mandrel

25, which is fixed to the shaft

26 having two rod clamps 27 and 28. The clamp 27 of the rod is placed behind the second cartridge 9 of the workpiece, and the clamp 28 of the rod is located between the cartridges 8 and 9 of the workpiece.

The work of the camp is as follows.

With a continuous process, the supply of the workpiece 24 is carried out by the cartridge 8 of the workpiece, and the cartridge of the workpiece 9 is produced by the engine 21 with the clutch 23 off, the fast supply of a new workpiece with the rod clamp 28 closed. The clamp 27 of the rod at this time is open for free passage of the workpiece 24.

When the workpiece 24 is fed by the workpiece cartridge 8, the clutch 22 is engaged, i.e., the gear 15 turns the engine 20 into idle mode.

After opening the rear clamp of the rod 28 and entering the subsequent workpiece, the clamp and feed are carried out by the workpiece chuck 9, while the workpiece chuck 8 opens and moves back. The direction and movement of the cartridges 8 and 9 of the workpiece are shown by arrows in FIG. 1.

In a batch operation mode (FIG. 2), when there are two tube blanks on the mill, the blank cartridge 8 is in the position shown in FIG. 2 positions and remains in that position. Its clamps are open and there is no obstacle to the rolling process. Open. Also clip; 27 mandrels and mechanisms of reciprocating movement and rotation of the screws are disconnected from the main engine. The feed is carried out only by the second cartridge 9 - the workpiece, the direction of movement of which is shown by a double arrow. At the same time, the necessary mill must be stopped to install a new tube billet.

In periodic operation, the clutch 22 and 16 are turned off, so that the workpiece cartridge 16 is stopped.

The proposed flock of pilger cold pipe rolling allows you to roll pipes that vary significantly in length by independently driving the movement and rotation of two workpiece cartridges and combines continuous and intermittent operation, which leads to an increase in its productivity.

Claims (2)

1. The patent of the Federal Republic of Germany No. 2449862, class, B 21 V 21/04, 1976, 2. The patent of Germany No. 2116604, cl. B 21 B 21/04, 1972. 27 P Z1 S 21 5, N j