SU835558A1 - Forming sleeve for producing thin-walled helical-seam tubes - Google Patents

Description

one

The invention relates to pipe production, more precisely, to the manufacture of welded pipes, and can most effectively be used in the molding of thin-walled spiral-seam pipes.

The known molding sleeve for the manufacture of spiral-seam tubes formed by two semi-articulated articulations interconnected, the inner surface of which is made smooth 1.

A disadvantage of the known sleeve is the high resistance to the molding, resulting in a loss of the longitudinal stability of the strip in front of the molding sleeve and, thus, in violation of the process of forming the tubular billet.

Also known molding sleeve, having a slot for the task in her strip; while the inner surface of the molding sleeve is provided with spiral grooves 2.

The disadvantage of this sleeve is also a high forming resistance, despite the fact that the area of contact of the strip with the inner surface of the forming sleeve is reduced as compared with sleeve 1.

This disadvantage is due to the fact that dry friction takes place between the strip and the inner surface of the sleeve due to the absence of lubricant between them.

Closest to the invention to the technical essence and the achieved result is a molding sleeve for the manufacture of thin-walled helical

pipes, having a slit for the task in it strips, a groove for installing an external shafting roller, spiral grooves made on the inner surface of the sleeve at an angle equal to the angle of approach of the strip, and a fitting for supplying lubricant to the spiral grooves 3.

In this molding sleeve, a noticeable decrease in forming resistance is achieved due to the lubricant supply to the spiral

grooves. However, in this sleeve, the resistance to molding is still significant, which often leads to a loss of the longitudinal stability of the strip and a violation of the stability of the process of forming a spiral-seamed tubular billet. In addition, there is a significant deterioration of the inner surface of the sleeve and the associated occurrence of traces of defects on the outer surface of the pipe being manufactured.

This is explained by the fact that the direction of the grooves coincides with the direction of movement of the strip in the molding sleeve, and thus lubrication occurs only in those parts of the strip where there are grooves, while

while in the contact areas of the strip with

The dry friction takes place on the dark surface of the sleeve.

The aim of the invention is to reduce the forming resistance and increase the durability of the molding sleeve by applying lubricant over the entire width of the friction surface.

The goal is achieved by the fact that in the molding sleeve for the manufacture of thin-walled spiral-seam tubes, made with a slot for the task into it stripes, a groove for installing the outer round shank roller and grooves on the inner surface of the sleeve, the grooves are made first along the quarter sleeve molding parallel to its longitudinal axis aggre gation, one relative to another, with the joint, and the length of the grooves along the axis of the hub corresponds to the pitch of the helix pipe produced.

FIG. 1 depicts the proposed sleeve, top view; in fig. 2 - section A-A of FIG. one.

The molding sleeve includes a housing 1 having a through bore, the inner surface 2 of which corresponds to the dimensions of the pipe being manufactured. In the housing 1, a slot 3 is made for the task of a strip therein and a groove 4 for mounting an outer round clamping roller (not shown). On the inner surface 2 of the sleeve there are two grooves 5 and 6, which are located in the first quarter of the sleeve in the course of forming, parallel to its longitudinal axis. While the first in the course of forming the groove 5 is located on the site of the groove 4, and the second groove 6 is mixed relative to the first and is located behind the groove 4. The grooves 5 and 6 through the nozzle 7 and the pipe 8 are connected to the lubricant feeder 9.

In the process, the strip 10 is continuously fed at an angle into the slot 3 of the molding sleeve. As a result, they are pressed against the inner surface 2 of the bushings and shaped into the tubular billet 11 with a helix seam, which is welded, for example, with HDTV. The lubricant through the nozzle 7 enters the grooves 5 and 6. Since the grooves 5 and 6 are arranged parallel to the longitudinal axis of the sleeve and, consequently, forming the tubular billet, the lubricant flows through the entire width of the strip 10, more precisely

the entire width of the friction surface between the strip and the inner surface 2 of the molding sleeve.

The invention will reduce the resistance to molding, increase durability

molding sleeve and eliminate the cause of the appearance of traces of defects on the outer surface of the manufactured pipe.

Claims (3)

Invention Formula Molding sleeve for the manufacture of thin-walled spiral-seam pipes, made with a slot for the task into her strip, a groove for installing an outer sheave pick roller and grooves on the inner surface of the sleeve, characterized in that in order to reduce the resistance to molding and increase durability by supplying lubricant across the entire width friction surfaces, grooves are made in first in the course of forming a quarter of the sleeve parallel to its longitudinal axis with displacement one relative to another, while the total length of the grooves along the axis of the sleeve corresponds to the step produced spiral pipe Sources of information taken into account in the examination 1. USSR Author's Certificate No. 200560, cl. B 21C 37/12, 1966. 2. USSR author's certificate number 247899, cl. B 21C 37/12, 1968. 3. USSR author's certificate No. 617105, cl. B 21C 37/12, 1977 (prototype).  five (0