RU2595163C2 - Cutting head for removal of inner flash ring in electric welded pipes - Google Patents

Abstract

FIELD: pipe.

SUBSTANCE: invention relates to production of pipes and can be used for removal of inner flash ring in production of pipes. Cutting head comprises housing 1 with rigidly fixed in it front and rear support rollers 4 and 5, tool holder 2 with cutter 3, lever 6 with pressure roller 8, elastic element 7 and secured in housing 1 adjustable stop made in form of adjusting screw 10, cylinder 11 with rod 9. Head is also equipped with spring 16 arranged between housing 1 and lever 6, and pressure roller 8 is made up of two parts spaced apart in transverse direction at a distance equal to 0.7…0.8 tube inner diameter.

EFFECT: use of invention improves reliability and wear resistance of cutting head with simultaneous increase of quality of welded tubes.

1 cl, 3 dwg

Description

The invention relates to the field of pipe production and can be used for the manufacture of electric-welded pipes with removal of internal burrs on pipe-welding mills.

When welding with pressure, the excess metal is displaced into grata on the outer and inner surfaces. The presence of burr limits the scope of electric-welded pipes, so its removal is one of the important technological operations.

Known cutter head for removing internal burrs in electrowelded pipes (RF patent 2100169, IPC VK 37/08, 1997, BI 36), comprising a housing with a pressure roller installed therein, support rollers and a tool holder with a cutter.

The disadvantages of the known technical solutions are that for the cutter head, perceiving cutting forces, the pipe blank is the support, the rigidity of which limits the limits of use, especially in the production of thin-walled pipes. Under adverse conditions, the rigidity of the technological system, the cutting process loses stability. The loss of stability of the system is characterized by the occurrence of vibrations - harmful periodic oscillatory movements. With vibrations, the quality of the treated surface deteriorates. The resistance of the cutting tool, especially carbide and mineral-ceramic, is significantly reduced. In addition, the wear resistance of the cutter head is reduced due to the influence of all kinds of foreign bodies falling inside the pipe. So, an indispensable companion for the production of electric welded pipes is scale and molten metal spatter. When welding pipes in the reflow mode, splashes and bursts are released in significant quantities, their accumulation can lead to breakage of the puller rod and to additional stops of the mill. In addition, when passing the transverse welded joint of pipes and during stops - starts of the welding process, the head design does not allow for the removal of the cutter from the pipe. As a result, the wear of the cutters increases significantly and even their destruction by cold sections of the inner burr is possible, which leads to a decrease in the reliability of the head and the quality of the pipes being welded.

The closest technical solution to the claimed and taken as a prototype is the "Cutter head for removing internal burrs in electric welded pipes" (RF patent 2199425 IPC V23K 37/00, publication date of 02.27.2003). The cutter head contains a housing with a pressure roller installed therein, support rollers, a tool holder with a cutter and a tool for clamping the cutter. The use of the cutter head ensures removal of the burr in the operating mode and the removal of the cutter (due to the termination of the pressing) when passing the transverse joint of the pipes, in case of an emergency shutdown of heating or when the mill stops.

The disadvantages of the known technical solution are that the removal of the cutter during the passage of the transverse joint of the pipes, in the event of an emergency shutdown of heating or when the mill stops, is not guaranteed, since the removal of the cutter head occurs spontaneously when the clamp is stopped, which leads to increased wear of the cutters and a violation of the stable cutting mode when removing grata. In addition, for the tool head, which perceives cutting forces, the support is a tube stock, the rigidity of which limits the use of the scraper, especially in the production of thin-walled pipes, which also increases the wear of the tool head and reduces the stability of the cutting mode when removing the burr, and thereby reduces the quality of welded pipes.

The solved problem of the invention is to increase the reliability and wear resistance of the cutter head by ensuring the forced removal of the cutter head, a stable cutting mode when removing the burr while improving the quality of the welded pipes.

The technical result from the use of the proposed technical solution is the creation of a highly efficient cutting head, which allows to obtain high-quality welded pipes.

The technical result is achieved by the fact that the cutter head for removing internal burr in electric-welded pipes, comprising a housing with support rollers rigidly fixed therein, mounted tool holder with a cutter, a lever with a pressure roller and an elastic element, an adjustable stop fixed in the housing, made in the form of an adjusting screw and a cylinder with a rod connected to the pipeline, according to the invention is equipped with a spring installed between the housing and the lever, and the supporting surface of the pressure roller is divided into two spaced part in the transverse direction by a certain distance in relation to the inner diameter of the pipe within 0.7 ... 0.8, based on the conditions of rigidity inner surface of the tube support.

To clarify the technical nature, consider figures 1, 2, and 3.

In FIG. 1 shows the cutting head in the working position.

In FIG. 2 shows the arrangement of the supporting surfaces of the pinch roller in the operating mode when removing the burr.

In FIG. 3 shows the arrangement of the supporting surfaces of the pinch roller in the forced cutter removal mode.

In FIG. 1-2 indicated:

1 - housing;

2 - tool holder;

3 - cutter;

4 - back roller;

5 - support roller front;

6 - lever;

7 - an elastic element;

8 - pressure roller;

9 - stock;

10-screw;

11 - cylinder;

12 - pipeline;

13 - hydroelectric station;

14 - set screw;

15 - fixing screw;

16 - spring.

The cutter head consists of a housing 1 with a tool holder 2 pivotally mounted in it with a cutter 3 and support rollers 4 (rear) and 5 (front). On the surfaces of the support rollers 4 and 5, grooves are made according to the dimensions of the weld (not shown in the figures). A lever 6 with an elastic element 7 is pivotally mounted on the axis of the front roller 5, for example, in the form of a disk spring. A pressure roller 8 is fixed on the lever 6. The bearing surface of the pressure roller 8 (see Fig. 2) is divided into two spaced parts in the transverse direction by a certain distance (the ratio of the distance to the inner diameter of the pipe is within 0.7 ... 0.8). The lever 6 through the elastic element 7 abuts against the rod 9 of the cylinder 11 fixed in the housing 1 and moved by the screw 10, connected to the pipeline 12. The tool holder 2 is pivotally mounted on the axis of the rear roller 4, is exposed in the housing 1 by means of a set screw 14 and fixed in it with using the fixing screw 15. A spring 16 is installed between the housing 1 and the lever 6.

The cutter head operates as follows. Using the set screw 14 and the fixing screw 15, the cutter 3 is set relative to the support rollers 4 and 5 to a certain height that defines the layer of the cut-off burr. After adjusting the head on the stand and installing it in the mill, the pipeline 12 is connected, for example, to the hydroelectric station 13. The mill is turned on and after approaching the cutter 3 of the heated internal burr, the hydroelectric station 13 is turned on. The pressure is transmitted through the pipe 12 to the cylinder 11, and the rod 9 moves under pressure The rod 9 through the elastic element 7 acts on the lever 6, which, turning on the axis of the roller 5, presses it down to the inner surface of the pipe (see Fig. 2). The pressure roller 8, mounted on the lever 6, is pressed against the inner surface of the pipe. As a result of this, the structure “bursts” inside the pipe and the cutter 3 installed in the tool holder 2 abuts against the pipe surface, cuts into the burr and cuts it off. The stroke of the rod 9 in the cylinder 11 is installed structurally, and the rod 9 always moves to the stop, i.e. by the same amount. The regulation of the force of pressing the cutter to the pipe is carried out by a screw 10, which, moving the cylinder 11, provides the required deflection of the elastic element 7 and the clamping force. Regulation is made at the stand or at stops through the "window" cut out in a pipe.

In the process, the elastic element 7 withstands a predetermined force of pressing the cutter to the pipe surface, ensuring the stability of the cutting of the burr. When passing the transverse joint of the pipes, in the event of an emergency shutdown of heating or when the mill stops, the pressure generated by the hydroelectric station is manually or automatically turned off. The rod 9 moves away from the lever 6, the spring 16 acts on the lever 6, which, turning on the axis of the roller 5, in the opposite direction pushes it up from the inner surface of the pipe. In this case, the roller 8, mounted on the lever 6, is pressed up to the inner surface of the pipe (see Fig. 3). As a result, the cutter 3 installed in the tool holder 2 is forcibly removed from the surface of the pipe and the possibility of damage is excluded.

When the support surface of the pressure roller 8 is divided into two parts in the transverse direction for a certain distance (the ratio of the distance to the inner diameter of the pipe is within 0.7 ... 0.8), the rigidity of the installation of the cutter head in the pipe increases. With increasing stiffness, the natural frequency of the system oscillations increases, and therefore the likelihood of vibrations is reduced, since with the increase in the frequency of the oscillations, the attenuation work of the system actually increases linearly. Under favorable conditions for the rigidity of the technological system, the cutting process becomes stable, the quality of the processed surface improves, and the resistance of the cutter increases.

Compared with the known analogues, the claimed technical solution allows to obtain a highly efficient cutting head, and due to the reliability and increased wear resistance of the cutters by ensuring guaranteed removal of the cutter when passing the transverse joint of the pipes, in case of an emergency shutdown of heating or when the mill stops and the stability of the cutting mode, improving the quality of the processed pipe surface.

In addition, due to the separation of the supporting surface of the pressure roller into two parts in the transverse direction at a certain distance, they ensure safety from all kinds of foreign bodies falling inside the pipe, which also affects the wear resistance of the cutting head.

Claims (2)

1. A cutting head for removing internal burrs in electric-welded pipes, comprising a housing with front and rear support rollers rigidly fixed therein, a tool holder with a cutter pivotally mounted on the axis of the rear support roller, a lever pivotally mounted on the axis of the front support roller with a pressure roller and an elastic element and an adjustable stop fixed in the housing, made in the form of an adjusting screw and a cylinder with a rod connected by a pipeline to a hydraulic station, while the rod is installed with the possibility of interaction action through an elastic element with a lever, characterized in that it is provided with a spring installed between the housing and the lever, and the pressure roller is made up of two parts spaced apart in the transverse direction by a distance equal to 0.7 ... 0.8 of the inner diameter of the pipe . 2. The cutting head according to claim 1, characterized in that the elastic element is made in the form of a disk spring.

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