Design

Punching holes in metal. Hole punching service

Punching holes and perforating material in the form of a sheet or pipes is a fairly popular operation. Today, there are several options for its implementation, which differ from each other in the equipment used, on which the quality and accuracy parameters depend.

Holes are drilled on drilling, milling or turning machines. Drills are used as a working tool. For the final molding of the hole, countersinks, countersinks, and reamers are used. With their help, ovals are eliminated, chamfers are formed, hole accuracy and surface cleanliness are increased.

To punch holes in metal, different presses are used - pneumatic, hydraulic, etc. The forces developed for the effective operation of a stamp consisting of two parts (a punch and a matrix) range from several kilograms to hundreds, or even thousands of tons.

Often in production, combined press - scissors are used to obtain holes.

This device consists of several mechanisms that allow you to process a metal profile, for example, a corner, cut metal strips, cut out in the form of straight or triangles, and, of course, a tool for punching holes in metal is installed on these scissors. As a rule, it consists of a punch and a matrix. The punch has a punch hole diameter. The matrix has a hole in its body corresponding to the size of the punch. Through it, cutting waste is removed.

It should be noted that the above methods for producing holes do not differ in high productivity, especially in conditions of large-scale or mass production. The advent of automated equipment eliminates this problem.

The use of equipment operating under the control of the CNC system has led to a decrease in the labor intensity of production processes, respectively, this has a positive effect on the cost of the finished product.
The fact is that the control program, which is entered before starting work, contains accurate data regarding the location of the holes on the sheet.

For example, a revolving punching machine is equipped with a drum on which punches (a tool for punching holes in metal) of different sizes and shapes are installed. When working, the program automatically selects the necessary tool. Such an engineering solution allows you to change the tool without stopping the machine, and increase the speed of obtaining the finished product. On equipment of this type, it is possible to obtain up to 1,500 holes per minute.
Getting the finished product consists of several operations. The first is laying a sheet of metal on the desktop. To fix it on it, clamps of various types are used.
After it is installed and fixed, the operator starts the control program. After that, the movement of the workpiece begins. According to the coordinates specified in the program, at the required point, the clamping device is lowered, fixing the sheet in the right place. After pressing, a blow occurs, applied by a punch (punch).

A rotary tool can be installed on the tool drum, which significantly expands the capabilities of the machine and allows cutting contours of complex shapes.
A press for punching holes in metal allows you to perform, in addition to punching, the following operations:

bullet - extrusion, obtaining edges of different directions;
molding;
non-final punching.

This method of obtaining holes implies that the holes will be obtained in a certain sequence. This operation can be used in the manufacture of both simple parts and rather complex metal structures. Such sheet metal processing requires high precision from the equipment and the control program, since errors in setup and program code can lead to substandard products.

Metal punching as a technological operation has existed for a long time, but in recent years, thanks to the emergence of systems with numerical software, it has changed significantly. Thus, modern equipment makes it possible to perform hole punching operations with an accuracy of their placement up to 0.05 mm. Coordinate punching equipment allows processing steel of different grades with a thickness of 0.5 to 8 - 10 mm.
Coordinate punching of a metal sheet is used in the production of body parts, fastening kits, etc. To obtain a set of holes, a series of punch strikes on the sheet is used. The breakdown order is entered into the control computer program. By the way, the use of computer programs and the appropriate tool for punching holes in metal guarantees the quality of finished products.

The use of coordinate punching presses for punching holes in metal provides a multiple increase in production speed and therefore it is used for large-scale and mass production of parts from a metal sheet.

Technology Disadvantages

It must be remembered that the quality of the resulting products directly depends on several factors, among them - the quality of the tool, equipment settings, quality factor of the software used to create the control program.

But it should be noted that, in principle, regardless of the method of obtaining a group of holes, defects in manual and automated punching are the same.

Hole offset

Most often, in the manufacture of a group of holes, one can encounter such a defect as the displacement of holes relative to each other or to the sides of the sheet. This defect may appear due to errors in the program, incorrect machine settings, etc.

Burrs

This defect appears due to the fact that the dimensions of the punch and die are incorrectly selected. In addition, burrs appear as a result of poor-quality tool sharpening.

Furrows

It is not uncommon for beards to appear on the surface of the hole along its axis. They are caused by the presence of defects in the surface of the punch.

cracks

The formation of cracks on the edges of punched holes is caused by the fact that their diameter is close in size to the thickness of the sheet.

Calculation of the required punching force

The process of punching metal is characterized by the fact that during this process a rather complex load pattern appears, which is concentrated in the area of the interaction point of the punch, the cut material and the matrix.

The punch is made in such a way that it enters the material not with its entire end face, but only with the outer annular part. The response comes from the matrix. Moreover, the pressure arising in the zone of interaction of these three components is distributed unevenly.

In other words, during the punching process, a couple of forces are generated that form a circular bending moment. Under its influence, the sheet bends. As a result of this bending, pressure is generated that affects the punch and the edge of the die. In addition, it is necessary to take into account the fact that tangential forces appear under the action of friction forces.
As can be seen from the above, an inhomogeneous force field arises during punching. Therefore, when carrying out calculations, a conditional value is used - shear resistance.
As a result of the research, the resistance depends not so much on the properties of the metal, but also on the level of hardening, cutting thickness, gaps in the punch/die pair, and the speed of the cutting process.

Hole punching in metal is carried out by means of a coordinate punching press - modern equipment with numerical control (CNC) and high-precision positioning mechanisms.

The punching of holes in the metal is carried out as follows. The workpiece is placed on the press table and rigidly gripped by special clamps. The sheet moves to a certain position under the turret, in which the punching tool is installed. Its lower part is called a matrix, the upper part, a punch, includes a clamping ring - a puller. The puller presses the sheet tightly against the matrix, after which punching occurs - the punch makes a hole in it. Then, under the action of powerful return springs, it returns to its original position. The number of tools in the revolver can be quite large (up to 32), which allows you to quickly punch holes of various sizes and shapes on one sheet. The index (rotary) tool, which can be installed in the revolver, greatly expands the possibilities for punching non-circular holes and various contours.

Hole punching as a technology has several important advantages. First of all, it allows you to process a metal sheet or a product of any geometry with the highest accuracy - up to 0.05 mm. Also, the metal punching machine has a very high productivity. Punching on the most modern equipment of this type is carried out at a speed of up to 1500 beats per minute. In addition to punching, coordinate punching presses allow you to perform the following types of operations:

incomplete punching;
molding;
puklevka.

Equipment for punching holes in metal offered by Abamet

For operations such as punching holes in metal, Abamet offers high-tech equipment of the trademark Abamet. It is designed and manufactured taking into account the latest trends and achievements in the metalworking and machine tool industries.

Hydraulic and electromechanical coordinate turret and CNC combined punch presses Abamet combine high performance, low energy consumption and low maintenance requirements. Also, this equipment has the following advantages.

The rigid O-shaped bed is subjected to vibration treatment twice during the manufacturing process to completely relieve internal stresses, then it is processed entirely on a high-precision large-sized machining center, which ultimately ensures the high accuracy of the machine.
The upper and lower plates of the turret are processed together, which allows for coaxial operation of the punch and die, significantly increasing tool life and improving the accuracy of machining parts.
Modern and reliable components of German and Japanese manufacturers for pneumatic and electrical systems provide high reliability and accuracy of the entire machine.
The brush table with lifting pneumatic ball supports of the sheet reduces the noise level during sheet movement, protects the sheet surface from damage and scratches, and reduces the risk of sheet deformation.
The machine is equipped with an automatic clamp protection function from falling into the punching area, which avoids damage to the tool and clamps.
The index tool rotation system is designed for simultaneous rotation of the punch and die according to the commands of the CNC system. The system is made using precision worm gears, which ensures high accuracy of the angle of rotation of the tool.

Abamet managers will tell you in detail about the possibilities Abamet equipment, its features and technology of sheet metal punching. All Abamet CNC punch presses come with an official 24-month warranty with no time limit.

Metal punching is an economical metalworking method that reduces production costs. Punching of sheet metal up to 4 mm thick allows you to produce both simple parts and complex metal structures.

Punching holes in metal - the main areas of application of the process and its features

Currently, this method of processing metal products is widely in demand in various areas of industrial production, in construction, in the manufacture of various structures and decorative elements. With its help, the most complex and responsible tasks are performed quickly and with maximum accuracy, taking into account the approved design and technical documentation, design solutions and personal wishes of the Customer of the service.

In the company "Tula Lift" you can order the punching of various metal blanks for the manufacture of:

Advertising structures
Industrial shelving
Trade showcases
Building supports and prefabricated elements
Details of machine tools, special vehicles and equipment
Enclosing structures

On modern, multifunctional equipment, metal punching ensures the production of holes of specified sizes and shapes: oval, round, rectangular and square. Individually made stamps and clichés make it possible to expand the range of offers and produce technological openings of the most non-standard designs. At the same time, in parallel with the main operations, the metal can be bent according to predetermined dimensions and drawings.

Metal punching - work execution technology

In order to make holes of the required shape and size in high-strength metal blanks, special automatic press machines with program control are used. They are equipped with high-precision parts and mechanisms that ensure high accuracy of the work performed. Control of the technological process and its reprofiling is carried out with the help of special programs that do not give failures and inaccuracies during metal processing.

Punching holes in metal is carried out at high speed in the process of moving parts or sheets along special guide structures. Such highly efficient devices make it possible, after the necessary measures, to obtain finished products, structures and elements with smooth edges. Prepared holes do not need additional refinement, processing and cleaning.

Benefits of metal punching at Tula Lift

The high-tech production facilities of the enterprise allow punching the necessary holes in a serial version or according to individual drawings of the Customer of the service. Cooperation with Tula Lift provides our clients with:

Ability to process a wide variety of types and thicknesses of metals
Large selection of metal blanks in the company's warehouse
Individual approach to all consumers
Optimization of costs and expenses, ensuring affordable cost and maximum validity of the service
Completion of work within agreed deadlines
The possibility of organizing the delivery of finished products to the customer's facility

In the design bureau of the company, you can order the development of exclusive design solutions, taking into account all the features and goals of the work.

When you need to make punching, boring or drilling holes in sheet metal at the lowest price, contact the NFZM metal structures plant. We have all the necessary equipment to quickly fulfill such orders.

With the CNC plasma cutting machine, you can quickly and accurately make a large number of holes of any shape according to a given drawing. But other methods are also possible.

One way to punch holes in sheet metal is with a punch. This is a punch (stamp), made of hard alloy, and a matrix to which it presses the workpiece. Punches come in different shapes and sizes.

Drilling and reaming holes in metal products is carried out on vertical drilling and radial drilling machines of various types, twist and core drills, which allow working with hard alloys.

Services for drilling and holes in metal

The plant has modern metalworking machines, including those with CNC, which have the following options:

Punching holes in metal and threading, costing from 16 rubles per product.
We work with a profile with a thickness of 0.9 mm to 20 mm with a hand tool with an accuracy of 3 microns.
Services of coordinate punching of metal are provided for grades st3, steel 09g2s, steel 10xsnd, structural, low-alloyed and stainless materials.
We can make holes in metal structures of round, oval, square and rectangular shapes of various diameters and with finished edges.

Our experts will select the type of tool with which punching, drilling or boring (boring) holes, including many of the same type, will be optimal for the alloy from which your workpieces are made. This will save time and minimize waste. Call for more information and prices for services.

Punching holes in metal

TO Category:

Assembly of metal structures

Punching holes in metal

Punching (punching) of holes is allowed for low-carbon steel up to 25 mm thick, low-alloy steel up to 20 mm, high-strength steel up to 12 mm inclusive at a temperature not lower than 0 °C. Holes formed by punching have tapers and burrs, as well as poorer mechanical properties of the steel in the area adjacent to the hole. Therefore, it is not allowed to punch holes in parts intended for riveted structures operating under dynamic load, as well as parts requiring high location accuracy.

For punching holes, punching (eccentric) combined and crank presses are used.

Punching press type K-2130 is designed for punching holes in sheet, sectional and shaped steel. The press consists of a C-shaped steel frame, which has a table in the lower part for attaching a pillow with a matrix. In the upper part of the bed there are guides along which the slider moves. A punch holder with a punch is attached to it. The slider is switched on to the working stroke by the punch enable handle or by pressing the foot pedal. The press can work on single and continuous strokes.

The punching press K-2130 with a force of 1000 kN is eccentric and single-stamp, that is, one punch (stamp) can be installed here and, therefore, one hole can be punched in one move. In some cases, two-stamp and multi-stamp presses are used, designed to simultaneously punch two or more holes. In this case, the punches (stamps) are located in the same plane parallel to the front of the press, at a distance of 80 ... 100 mm from one another.

Crank presses with a force of 1600 are used as multi-stamp presses. .8000 kN, since eccentric punching presses are produced with a force of 0.8 ... 1 MN, which ensures punching only one hole in one stroke.

In workshops and factories of low power, combined punching shears are used for punching holes, which can punch holes and cut shapes.

For punching holes, the part is placed between the punch and the matrix. When the press is turned on, the punch goes down and presses the part against the die. The matrix is fixed in the press pad motionlessly. Under the pressure of the punch, compressive and shear stresses occur in the part, concentrated along the perimeter of the cutting edges of the punch and matrix. The punch, overcoming resistance, penetrates deep into the thickness of the steel, squeezing it into the die hole. The amount of penetration of the punch into steel with a carbon content of 0.2% until complete chipping is 40% of the steel thickness.

The punch (stamp) consists of a working and a tail part, which serves to fix the punch in the punch holder of the press, together with which it performs a reciprocating motion. The diameter of the working edge of the punch must be at least 2 mm larger than the punched steel. The diameter of the cutting edge of the punch is assumed to be equal to the nominal size of the hole, and the diameter of the hole in the matrix is greater than the diameter of the punch by the gap. The gap, mm, for punched steel with a thickness of 4.. .8 mm is 0.7, with a thickness of 9..12 mm-1.2; 13 ... ... 17 mm-2; 18…19 mm-2.6; 20..21 mm - 2.65; 22.. .25 mm-3.6.

Rice. 1. Punching press: 1 - bed, 2 - pillow. 3 - punch holder, 4 - switching handle

Punches are made with a cone at the end and without a cone. A punch without a cone is used when punching holes without basting according to templates. When punching holes along cores, the punch cone enters a conical recess 2–3 mm deep, formed when marking or basting on the surface of the steel being machined with a center punch, fixes the end of the punch and increases its stability under the action of punching forces. To reduce the friction forces of the punch against the wall of the hole during punching, its working part is made conical and ground from the end and along the conical surface, thereby forming a cutting edge,

When punching holes, it is very important that the tool works without breakage and chipping of the cutting edges. It depends on the quality of the steel used to make the tool, the quality of the tool, the heat treatment and the grade of the steel being pierced.

Matrices and stamps are made from alloyed tool steel grades 5XV2S and Kh12M or from carbon tool steel grades U8A and U9A.

Depending on the profile of the steel, the thickness, dimensions and weight of the part, serial production, the required accuracy, the number of holes and their location, the holes are punched according to a template, a basting using fixtures or special installations.

In sheet parts with an area of up to 0.5 m2 and a mass of up to 20 kg, holes are punched according to a template on a single-stamp press. The presser puts the template on the part, feeds it to the press table, aligns the hole on the template with the press stamp, punches a hole in the part, moves it and the template, removes the template from the part, removes the part and puts it in a stack or container. In corners up to 1 m long and weighing up to 20 kg, holes are punched according to templates in the same sequence.

In sheet parts with an area of up to 0.5 m2 and corners up to 1 m long, holes are punched along the basting on single-stamp presses in this sequence. The presser brings the part to the press table, sets the part under the stamp, aligning the tip of the stamp with the core on the part, punches a hole in the part and moves it to punch the next holes. Then the part is removed from the press and placed in a stack or container. Works presser sitting.

Rice. 2. Scheme of punching holes: 1 - nut for fastening the punch, 2 - punch, 3 - cone, 4 - steel being processed, 5 - shearing plane. 6 - matrix, 7 - pillow, 8 - conical recess

For punching holes along the basting in the corners of great length, in order to support and move the corners, the press is equipped on both sides with disk rollers. The rollers are mounted on racks at a distance of 1000 ... 1500 mm from one another. On the feed side of the corners there is a loading table, the level of which is slightly higher than the level of the rollers. A batch of corners is fed onto the loading table by an overhead crane, which the presser and his assistant one by one place on a shelf without holes between the roller disks. The corner is easily moved along the rollers by the presser, who alternately directs and aligns the marked holes with the stamp cone. After punching holes, the corner is removed with an overhead crane and stacked on gaskets.

To punch holes in the second push, a pack of corners with holes is returned to the loading table and holes are punched in the same way as in the first shelf.

When organizing a workplace for punching holes, the following rules are followed.

Containers with small parts are installed near the workplace from the side opposite to the control handles. Platforms for storing workpieces are located at the supply roller conveyors or tables, and finished parts - at the receiving conveyors or tables.

Before starting work, they check the press at idle, lubricate it, adjust the local lighting so that the light does not blind the presser. Parts are laid strictly horizontally to the plane of the matrix without distortions and kinks, this is especially monitored when punching holes in large sheet parts supported by overhead cranes.

The press biscuit is always turned on completely to avoid its back ejection. In order for the punch not to break, it must enter the matrix without distortion. A template for punching holes is attached with clamps so as not to hurt your hands. After finishing work and turning off the press, the workplace is cleaned.

Rice. 3. Scheme of the organization of the workplace when punching holes: 1.4 - disk rollers, 2 - loading table. 3 - punch press, 5 - stack, 6 - presser