CN114101784A

CN114101784A - Elastic flat fixed-length shearing method for stepped shear blades

Info

Publication number: CN114101784A
Application number: CN202111573924.7A
Authority: CN
Inventors: 帅虹全; 张国华; 陈海军
Original assignee: Xinjiang Bayi Iron and Steel Co Ltd
Current assignee: Xinjiang Bayi Iron and Steel Co Ltd
Priority date: 2021-12-21
Filing date: 2021-12-21
Publication date: 2022-03-01

Abstract

The invention discloses a method for elastic flat fixed-length shearing with a stepped shearing edge, which is implemented according to the following steps: 1. increasing the length of the lower shear blade from 750mm to 800mm, so that the lengths of the upper and lower shear blades are consistent, and the effective shearing length of the upper and lower shear blades is increased; the upper shear blade is designed and manufactured into two steps: the step height difference between the high shearing edge area and the low shearing edge area is half of the elastic-flat thickness during shearing; 2. after adopting cascaded cutting edge, overlap ratio is big when high shear edge district is cuted, exceeds 10mm, adjusts two parameters of cutting edge clearance and cutting edge overlap ratio: the blade clearance is increased from the common 0.3mm to 0.5mm during installation; reducing the contact ratio from 5mm to 2mm based on one end of the low-shear edge area; 3. designing and manufacturing a separation chute at a roller way before shearing, dividing the flat bullets entering a shearing edge area in rows into two parts, and dividing one part of the bullets into a low shearing edge area; a portion is diverted to the high shear region. The method can double the shearing efficiency of the fixed-length shears.

Description

Elastic flat fixed-length shearing method for stepped shear blades

Technical Field

The invention relates to a flat and flat fixed-length shearing method of a stepped shearing blade.

Background

Background art 1: in recent years, the automobile industry in China is developed rapidly, and heavy load and high efficiency are pursued for trucks. The requirements on the spring steel plate with the functions of shock absorption and bearing are higher and higher correspondingly, and the requirements on the section of the spring steel plate are higher and higher. At present, the requirement on the specification of the spring steel plate in China is that the thickness reaches 40mm, and the width reaches 120 mm. Background art 2: the base material for manufacturing the spring steel plate is spring flat steel rolled and produced by a steel plant. Most steel mills adopt a fixed-length shearing process to shear and collect the spring flat steel when producing the spring flat steel. The spring flat steel has high hardness and high strength, and when the section size is large, the shearing capability of the fixed-length shear is insufficient. The shearing count is forced to be reduced on site, and the production efficiency is influenced. And (3) searching documents: (1) sun Yingzi, optimization of a rod line cold shearing area sizing shearing control system, mechanical engineering and automation 2016 (6) months; (2) in the ocean, the application and practice of the cut-to-length shear of the production line of fine bars, which is 5 months in 2017 of the Chinese high and new technology enterprise; (3) yang Xiongying, Lin Yongming, a device for improving the cutting capability of cold shears to large-size bars, 2014; (4) the Song Jian, Wangqiang and Chenwen oven improve the production practice of the rod sizing rate, and the Sichuan metallurgy is 2019 years. As can be seen from the above search documents, in the prior art, the method for improving the shear capacity of the bar material in the fixed length mode mainly adopts the mode of improving the bearing capacity of the crankshaft or enlarging the whole equipment, and there is no application technology for improving the shear capacity by designing a novel shear blade and changing the shear mode.

When large-scale bullet flat is produced in domestic steel mill, most all have the scale and cut the not enough problem of ability. Eight small-size unit scale of steel are cut for 450 tons of combination formula swing scissors, and cutting edge length: 800 mm; maximum shear force: 450 tons; maximum shear area in the process of producing elastic flat: 3600mm². The size of the bullet below 20x90mm can be cut only two at a time, and the size of the bullet above 20x90mm can be cut only one at a time. The shearing efficiency is very low, and the performance of the large-specification flat-elastic capacity of the eight-steel small-sized unit is seriously influenced.

Disclosure of Invention

The invention aims to provide a method for shearing flat springs to a fixed length by using a stepped shear blade, which can double the shearing efficiency of the fixed length shears by designing a novel shear blade and optimizing the shearing method, and solves the bottleneck problem of low fixed length shearing efficiency when a steel plant produces large-size flat springs.

The technical scheme adopted by the invention is as follows: a method for shearing a stepped shear blade into flat and elastic fixed length is implemented according to the following steps: 1. increasing the length of the lower shear blade from 750mm to 800mm, so that the lengths of the upper and lower shear blades are consistent, and the effective shearing length of the upper and lower shear blades is increased; the upper shear blade is designed and manufactured into two steps: the step height difference between the high shearing edge area and the low shearing edge area is half of the elastic-flat thickness during shearing; 2. after adopting cascaded cutting edge, overlap ratio is big when high shear edge district is cuted, exceeds 10mm, adjusts two parameters of cutting edge clearance and cutting edge overlap ratio: the blade clearance is increased from the common 0.3mm to 0.5mm during installation; reducing the contact ratio from 5mm to 2mm based on one end of the low-shear edge area; 3. designing and manufacturing a separation chute at a roller way before shearing, dividing the flat bullets entering a shearing edge area in rows into two parts, and dividing one part of the bullets into a low shearing edge area; a portion is diverted to the high shear region.

And correcting the installation parameters of the shear blades by observing the levelness of the section of the shear fracture and the coincidence condition of the upper shear blade and the lower shear blade. The blade clearance is increased from the common 0.3mm to 0.5mm during installation; the overlap ratio is reduced from the usual 5mm to 2mm, based on the lower end of the cutting edge on the step. The problem of 'cutting edge gnawing' caused by overlarge overlap ratio of the high-end part of the upper cutting edge can be avoided through the optimization and correction of the two parameters. The stepped cutting edge bullet flat fixed length shearing technology is put into use in an eight-steel small-sized unit in 2021 month and starts to be applied, ten thousand tons of large-sized bullets are sheared, and the using effect is good. The fixed-length shearing efficiency of the large-size elastic flat is increased from the original 50 tons/hour to 100 tons/hour. The production capacity level of the large-size flat bullet of the eight-steel small-sized unit is greatly improved. The shearing section is parallel and level, and the quality is good without the defects of burrs and the like. During shearing operation, tracking verification is carried out on the shearing current load of the transmission motor of the fixed-length shear, when 20x90 is sheared and the steel is sheared to be flat, the shearing current load of the motor is between 1110 and 1140A, when 2 steel is sheared, and when 4 steel is sheared by adopting the stepped shearing edge technology, the shearing current load of the motor is between 1120 and 1140A, and the loads of the two are basically consistent. It is demonstrated that the shear efficiency can be doubled without increasing the shear load with this invention. The invention can be transplanted to the fixed-length shearing of steel products such as large-section round steel, section steel and the like, has no special limitation, and has stronger popularization and application prospects.

Drawings

FIG. 1 is a schematic view of a shear blade according to the present invention;

figure 2 is a view of the cutting edge of the present invention in an operative condition;

figure 3 is a view of another state of operation of the cutting edge of the present invention.

Detailed Description

A flat and elastic fixed-length cutting method of a stepped cutting edge is implemented according to the following steps as shown in figures 1, 2 and 3: 1. increasing the length of the lower shear blade from 750mm to 800mm, so that the lengths of the upper and lower shear blades are consistent, and the effective shearing length of the upper and lower shear blades is increased; the upper shear blade is designed and manufactured into two steps: the high-shearing edge area 2 and the low-shearing edge area 1 have a step height difference L1 of half the elastic-flat thickness during shearing; 2. after adopting cascaded cutting edge, overlap ratio is big when high shear edge district is cuted, exceeds 10mm, adjusts two parameters of cutting edge clearance and cutting edge overlap ratio: the blade clearance is increased from the common 0.3mm to 0.5mm during installation; reducing the contact ratio from 5mm to 2mm based on one end of the low-shear edge area; 3. designing and manufacturing a separation chute at a roller way before shearing, dividing the flat bullets entering a shearing edge area in rows into two parts, and dividing one part of the bullets into a low shearing edge area; a portion is diverted to the high shear region.

Taking 20x90mm elastic flat shearing as an example, the fixed-length shear before modification can only shear two elastic flat at most once. By adopting the technology of the invention, the roller way before shearing can simultaneously convey four flat bullets, and two of the bullets are conveyed to the low shearing edge area 1 and the other two bullets are conveyed to the high shearing edge area 2 by the separation chute (the prior art). During shearing, the upper shearing blade moves downwards, the high shearing blade end firstly touches the flat spring for shearing, only two flat springs at the high shearing blade end are sheared at the moment, and the flat spring at the low shearing blade end does not start shearing yet, as shown in figure 2; the shearing blades continue to move downwards, the high-shearing-blade end is contacted with the bullet flat to continue shearing after the bullet flat is sheared, and only two bullet flat are sheared at the time, as shown in figure 3. Therefore, under the condition that the shearing capacity of the fixed-length shears is not exceeded, the shearing efficiency of the fixed-length shears is directly doubled, and the large-size flat elastic capacity is greatly improved.

Claims

1. A method for shearing a stepped shear blade into flat and elastic fixed length is characterized by comprising the following steps: 1. increasing the length of the lower shear blade from 750mm to 800mm, so that the lengths of the upper and lower shear blades are consistent, and the effective shearing length of the upper and lower shear blades is increased; the upper shear blade is designed and manufactured into two steps: the step height difference between the high shearing edge area and the low shearing edge area is half of the elastic-flat thickness during shearing; 2. after adopting cascaded cutting edge, overlap ratio is big when high shear edge district is cuted, exceeds 10mm, adjusts two parameters of cutting edge clearance and cutting edge overlap ratio: the blade clearance is increased from the common 0.3mm to 0.5mm during installation; reducing the contact ratio from 5mm to 2mm based on one end of the low-shear edge area; 3. designing and manufacturing a separation chute at a roller way before shearing, dividing the flat bullets entering a shearing edge area in rows into two parts, and dividing one part of the bullets into a low shearing edge area; a portion is diverted to the high shear region.