RU2291034C2 - Disc saw for metallic articles - Google Patents

Abstract

FIELD: apparatuses for cutting metallic articles, possibly cutting metallic products in continuous shape bending and tube welding mills.

SUBSTANCE: disc saw includes disc having cut-off teeth along its outer surface. Saw is provided with segments with trimming members for cutting secured to sites provided in windows formed uniformly along perimeter of outer surface of disc. Trimming member of each segment are in the form of radial or end teeth. Segments with radial trimming members are arranged alternatively with segments with end trimming members. Radial teeth are arranged along circle whose diameter is less by 1.0 - 1.5 mm than diameter of outer surface of disc. Radial feed for tooth equal to 0.01 mm is provided. End teeth are arranged along circle whose diameter is less by 2 - 3 mm than diameter of circle along which radial trimming teeth are arranged. Cut-off teeth are arranged between said windows.

EFFECT: possibility for cutting continuously moving shapes and tubes in lines of shape bending and tube welding mills with high speed of welding, improved quality of cutting ends of tubes.

4 cl, 6 dwg, 1 ex

Description

The invention relates to the field of metal cutting, and more specifically to circular saws for cutting metal products, and can most effectively be used in continuous roll forming and tube welding mills.

One of the bottlenecks of continuous pipe welding mills is a “flying” cutting device. In the production of welded pipes with a diameter of 20-108 mm at a speed of 90 m / min and its subsequent cutting on the move with a length of 6 meters, to ensure the continuity of the technological process, the saw of the cutting device should have a peripheral cutting speed of up to 96 m / s and a feed of 180 mm / s, with In order to increase the resistance of cutting teeth and the quality of the ends of the pipes, the feed rate per tooth should be as small as possible.

According to the value of the peripheral cutting speed, the saws of pipe welding mills approach friction saws, which, without teeth, must rotate with a peripheral speed of 120-150 m / s and have a feed of 1.5 cm ² / s (see Veselovsky S.I. ., Cutting of materials, Moscow, Engineering, 1973, p.218-219).

The ends of the cut pipes to comply with regulatory documents after cutting are traditionally trimmed on metal cutting machines, which require additional production space, maintenance personnel and financial costs.

Due to the short pipe cutting cycle, a large number of saw blades are used in pipe welding mills, and therefore, to reduce the cost of pipe production, they should have the maximum possible tooth resistance and the minimum manufacturing cost.

Of the known circular saws for cutting metal products, the closest in technical essence is the circular saw for cutting metal products described in A.S. USSR No. 1298010, class In 21 D 1/02, declared. 10/02/85, publ. 03/23/87

This circular saw for cutting metal products contains a disk with cutting teeth placed on its outer surface. The teeth of the saw blade are made in the form of a segment within the angle of 120-180 ° and are cutters installed in the grooves of the disk. The drive has a swing drive. The cut metal product rotates during the cutting process. When the metal is rotated, each detachable tooth of the disk, when in contact with the outer surface of the metal, removes chips of a certain thickness in one revolution. When the disk is rotated by 120-180 °, metal products are cut.

A disadvantage of the known design of a circular saw for cutting metal products is that it cannot be used in continuous roll forming and tube welding mills for cutting continuously moving profiles and pipes leaving the mill at high speed (90 m / min).

Another disadvantage of the known design of a circular saw for cutting metal products is that when cutting pipes leaving the mill at high speed, large burrs and even a “beard” will occur at the ends of the pipes, which reduces the quality of the cut.

The objective of the present invention is to create a circular saw for cutting metal products, which allows for high-speed welding to cut continuously moving profiles and pipes in the lines of roll forming and tube welding mills and to improve the quality of cutting of the ends of the pipes.

The problem is achieved in that the circular saw for cutting metal products, containing a disk with cutting teeth located on its outer surface, according to the invention is equipped with segments with cleaning cutting elements, mounted on platforms placed in windows evenly running around the outer surface of the disk, cleaning cutting elements on each segment are made in the form of radial or end teeth, and segments with radial grinding teeth are placed alternately with segments with end teeth and grinding teeth, while the radial teeth are located on a circle smaller in diameter of the outer surface of the disk by 1.0-1.5 mm, and are designed to provide a radial feed to the tooth of 0.01 mm, the end teeth are located on a circle whose diameter is smaller 2-3 mm of the diameter of the circle on which the radial stripping teeth are placed, and the cutting teeth are located between the windows.

Each segment with radial grinding teeth has at least two teeth of similar shape and size to the cutting teeth and having a width greater than 0.1-0.3 mm of the width of the cutting teeth. In addition, the end stripping teeth are made on both sides of each segment and are directed toward the axis of rotation of the disk, while the segments with the end stripping teeth in the middle plane of the disc are divided into two equal parts with the formation of reduced cross sections at the base of the cut. The surfaces of the radial and end teeth are coated with wear-resistant material.

Such a constructive implementation of a circular saw for cutting metal products will ensure high-quality welding of high-quality cutting of profiles and pipes in the lines of continuous roll forming and tube welding mills and improve the quality of cutting the ends of the pipes.

This is achieved due to the fact that the process of cutting a continuously moving pipe in a pipe welding mill is carried out in three stages:

- Rough cutting of the pipe (more than 93% of the cutting work volume) with cutting teeth made on the outer surface of the disk with the smallest possible feed to the tooth.

- Finishing the ends of the cut pipe with radial grinding teeth made of alloy steel with subsequent wear-resistant coating. Cross-cutting is carried out with the smallest possible radial feed per tooth and machining allowance.

- Finishing of the ends of the pipe being cut by the face grinding teeth made of alloy steel and coated with wear-resistant material. End-end machining of the ends is carried out with the smallest possible radial feed and pressing the cutting teeth to the ends due to centrifugal forces arising from the rotation of the disk.

To explain the invention, a specific embodiment of the invention is provided below with reference to the accompanying drawings, in which:

figure 1 shows a circular saw with segments for cutting metal products,

figure 2 - place I in figure 1;

figure 3 - place II in figure 2;

figure 4 is a section aa in figure 2;

figure 5 is a section bB in figure 3;

figure 6 - section bb in figure 3.

A circular saw with segments for cutting metal products contains a disk 1 with a diameter of D ₁ made of carbon steel, along the perimeter of the outer surface of which there are evenly made windows 2, in which there are 3 platforms for fastening with rivets 4 segments 5 with stripping cutting elements made in the form of radial 6 or end 7 teeth. On the outer surface of the disk 1 between the windows 2 are cutting elements of cutting 8 in the form of teeth. All segments are made of alloy steel. Segments 5 with radial 6 grinding teeth are placed in the windows 2 in turn with segments 5 with end 7 of the grinding teeth 7. Each segment 5 with radial 6 grinding teeth has at least two teeth 9, similar in shape and size to the cutting teeth 8, but located on a circle D ₂ smaller than the diameter of the outer surface D _{1 of the} disk 1 by 1.0-1, 5 mm, and having a width H ₁ greater _than 0.1-0.3 mm of the width H _{2 of the} cutting teeth 8. In each segment 5, the end 7 grinding teeth are made on both sides and are directed towards the axis of rotation of the disk. Moreover, they are located on a circle whose diameter D ₃ is 2-3 mm less than the diameter D _{2 of the} circle on which the radial 6 grinding teeth are located. Segments 5 with end 7 grinding teeth in the middle plane of the disk by means of the slot 10 are divided into two equal parts 11 with the formation of reduced cross-sections 12 at the base of the slot 12. The surfaces of the radial 6 and end 7 teeth are coated with wear-resistant material. In the center of the disk 1, a cylindrical hole 13 for installation and a hole 14 for attaching a circular saw to a spindle (not shown) of a cutting device are made. Parts of 11 segments 5 have entry chamfers 15, 16.

The circular saw is mounted on the spindle of the cutting device.

A circular saw for cutting metal products as part of a cutting device when cutting pipes in a continuous pipe welding mill operates as follows (the equipment of the mill is not shown).

After the carriage of the cutting device is accelerated to the welding speed on the mill, the continuously moving pipe is clamped. With the vertical movement of the spindle with the saw until it contacts the outer surface of the pipe with the help of a hydraulic cylinder, its cutting begins with the cutting teeth of the 8th disc 1. After the introduction of these teeth into the pipe body by 0.5-0.75 mm, the teeth of 9 segments enter the work of cutting the pipe 5 . Having a width H ₁ greater _than 0.1-0.3 mm in width H _{2 of the} cutting teeth 8 of the disk 1, the teeth 9 coated with wear-resistant material will clean the ends (fair trimming) formed after cutting the pipe with teeth 8. Finishing of the ends is ensured high with cutting speed (96 m / s), low radial feed per tooth (0.01 mm) and small machining allowance (0.05-0.15 mm). After the teeth 8 are embedded by 1.5-2 mm into the body of the ends, the end teeth of 7 segments 5 enter the work on the final cleaning of the ends formed as a result of cutting of the cutting teeth 8 of the disk 1 into the body of a continuously moving pipe 5. The pressing is divided by a groove 10 parts of 11 segments 5 with end cleaning teeth 7 to the machined ends of the pipe is carried out due to the deflection of these parts relative to the reduced cross-sections 12 from the bending moment. The magnitude of this moment is determined by the product of the part 11 of segment 5 arising during the rotation of the disk with the centrifugal force segments R _c of the segment 11 with the end cleaning teeth on the shoulder h equal to the distance from the center of mass of these teeth to the middle of the reduced cross sections 12. The maximum allowance for processing of each end face is determined from :

where P _t - the maximum possible end allowance, mm;

δ _t - end runout of the saw blade when rotating it together with the spindle of the cutting device.

To reduce the shock loads on the segments 5 when trimming part 11 of the segments 5 have entry chamfers 15, 16.

After the cutting and grinding teeth pass the entire cross section of the pipe being cut, the process of cutting and processing the ends of the continuously moving pipe ends. The saw with the help of the hydraulic cylinder returns to the upper initial position, the pipe is released from the clamp, the carriage of the cutting device returns to its original position.

Next, the cycle repeats.

The proposed circular saw for cutting metal products in comparison with the known ones will allow for the cutting of continuously moving profiles and pipes in the lines of roll forming and tube welding mills and to improve the quality of cutting the ends of the pipes.

Claims (4)

1. A circular saw for cutting metal products, comprising a disk with detachable teeth located on its outer surface, characterized in that it is equipped with segments with cleaning cutting elements fixed to platforms located in windows made uniformly around the outer surface of the disk, cutting cleaning elements on each segment is made in the form of radial or end teeth, and segments with radial grinding teeth are placed alternately with segments with end cleaning teeth, while for The tooth teeth are located on a circle smaller in diameter of the outer surface of the disk by 1.0-1.5 mm, and are made with a radial feed of 0.01 mm onto the tooth, the end teeth are located on a circle whose diameter is 2-3 mm less the diameter of the circle on which the radial stripping teeth are located, and the cutting teeth are located between the windows. 2. The circular saw according to claim 1, characterized in that each segment with radial grinding teeth has at least two teeth similar in shape and size to the cutting teeth and having a width greater than 0.1-0.3 mm of the cutting width teeth. 3. The circular saw according to claim 1, characterized in that the end cleaning teeth are made on both sides of each segment and are directed towards the axis of rotation of the disc, while the segments with end cleaning teeth in the middle plane of the disc are divided into two equal parts by means of a slot to form at the base of the slot reduced cross-sections. 4. A circular saw according to any one of claims 1 to 3, characterized in that the surfaces of the radial and end teeth are coated with a wear-resistant material.

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