A punching press is equipment for cold forming of metals.
It is used mainly for punching various holes in sheet metal.
The principle of operation is based on the conversion of external energy into potential energy through transmission to the actuator, while the metal is separated by pressure using a movable tool that shifts the material relative to a stationary tool. Such equipment is manual, which in turn is divided into lever-screw and hydraulic.
On hand presses, holes of no more than 20 mm are punched. in metal up to 20 mm thick. The main convenience is that due to their small size they are easy to move. There is drive (mechanical) equipment based on a crank (eccentric) shaft.
Mechanical punching presses come in vertical and horizontal types. They are used to speed up the process of punching holes in structural parts that are manufactured in mass and serial production. They can have a large number of holes and punches in the matrix.
There are divisions of hole-punching presses by design into single-stamp, two-stamp, four-stamp and multi-stamp. Not all mechanical presses are created equal in performance.
In a sheet bending machine equipped with a multi-stamp tool, the punches work in steps and due to this, it is possible to obtain greater productivity than in others.
For mass production, hole punching is used on vertical copy presses with a duplicator table. The latter are designed for punching holes of any shape and arbitrary location.
Design
The design of the hole punching press consists of a vertical frame where on the lower working surface there is a matrix for the punch and the punch itself is fixed above the matrix in a slider that receives movement from an eccentric and makes reciprocating movements in special guides.
There are hole-punching presses with program control, which are designed with a table moving in perpendicular directions and a turret head, the mechanism of which is equipped with a drive that programmably sets the tool to the punching position.
Hydraulic Punch Press is an indispensable assistant for punching holes in metal (sheet, angle, channel, etc.). The punching press is a C-shaped frame with a hydraulic cylinder of direct vertical stroke, due to which punching is performed with maximum quality and tool life. PM series machines are designed for punching holes in metal with a thickness of 2mm to 35mm. Punching presses can be equipped with systems for automatic feeding and positioning of the workpiece (sheet, angle, channel).
PM punching press require manual positioning of the workpiece by the operator. To facilitate the positioning of sheets and other assortments, the press includes a small supporting table with a ruler and stops. For more accurate positioning of the workpiece, punching presses are equipped with an inexpensive system for laser indication of the punching center, and for productive periodic punching of holes - an extended table with adjustable stops, or a CNC-controlled feed table.
Distinctive feature of hydraulic punching presses PM series are:
- The highest quality hole punching (smooth hole edges and minimal deformation), while ensuring maximum tool life (punch and die).
- Hydraulic cylinder with fast return stroke - significantly reduces waiting time when moving the punch up.
- Ease of tool setup and operation. All Sunrise punching presses have a low-pressure mode, that is, when adjusting (replacing) the punch/die, to check the gaps, the hydraulic cylinder with the installed punch is lowered with the minimum possible pressure and speed, thus, if the tool is installed incorrectly, it will not break .
- Possibility of using special tools to perform operations: cutting corners, strips, rods, cutting grooves.
Hydraulic punching presses from the Sunrise company (Sunrise) -This is truly impeccable quality equipment. Sunrise is one of the world's three largest manufacturers of shear presses, punching presses and automation systems, with an annual production of about 2,000 machines. You can read more about Sunrise and its advantages over other competing companies in the “ABOUT THE COMPANY” section.
| Punching holes in sheet and strip. | Sheet cutting and stripes. | Corner cutting (straight) | Rectangular cutting out a groove. |
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| Punching holes in the corner and channel. | Sheet bending and stripes. | Bar cutting (straight) | Triangular cutting out a groove. |
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| Punching holes in the pipe. | Corner bending. | Channel cutting (straight) |
Explanation of the abbreviation in the name of PM hydraulic punching presses:
- P.M.= "PunchMachine", that is, a machine for punching holes.
- 55 (digit) - force of the punching hydraulic cylinder (tons).
- T(LT/XT)- depth of the bed mouth (distance from the punching punch to the bed). "T" = 310mm, "LT" = 510mm, "XT" = 760mm.
- Example: Model PM-80LT means a punching press with a force of 80 tons and a throat depth of 510mm.
Hydraulic punching press PM-35T (LT/XT)- the most popular for comfortable work with sheets up to 10-12mm, as well as a wide range of assortments (angle, channel, etc.). With a compact design and high-speed hydraulic cylinder, the PM-35 presses are ideal for versatile work in any production area.
Hydraulic punching press PM-55T (LT/XT)- excellent combination of medium power, high speed and compact design. In addition to punching holes, punching presses allow you to bend sheets/angles, cut grooves and cut assortments using additional equipment.
Hydraulic punching press PM-80T (LT/XT)- productive machines of medium power, with a compact design. They work comfortably with workpiece thicknesses up to 20mm. They are often equipped with a CNC feeding table for automatically moving sheet blanks according to a program. Suitable for a wide range of production tasks.
Hydraulic punching press PM-120LT/XT- powerful machines with a deep bed opening. They work comfortably with workpiece thicknesses up to 20 - 25mm. To move heavy sheets, they are often equipped with a CNC-controlled feeding table. Popular in the production of metal structures.
5.00 /5 (100.00%) 4 voted
Punching holes. Punching press.
Punch and matrix.
When punching holes, the role of the upper movable knife is played by the punch (stamp), and the lower, stationary knife is played by the matrix (stamp). The hole formation process and the working parts of the punching device are shown in Fig. 1.
The end of the punch entering the matrix and the hole in the matrix have the shape of a truncated cone with its apex facing upward. The cutting edges of the punch and matrix have angles of 99°, the bevel angle is 1°. With this shape of the punch, friction is reduced as it passes through the metal being pierced. With the conical shape of the die hole, the extruded metal easily falls out of the die hole.
Fig.1. Metal punching:
1 – punch; 2 – matrix.
Punches and dies are made of tool carbon steel and are made interchangeable, that is, they are manufactured according to certain standards.
To punch a hole, the sheet is laid so that the core A . delivered on the sheet when basting, it fell exactly under the taper of the punch. Then the punch is turned on, which, by pressing the sheet between the cutting edge in the matrix and the cutting edge b punch, chips metal.
Lever and screw bearer.
The holes are pressed manually using lever presses and presses. Two types of bears are used: lever and screw. The screw bearer (Fig. 2, a) has the appearance of a steel bracket; it can be forged or cast. There is a fixed matrix at the lower end of the bracket, and a screw with a punch passes through its upper end. The sheet is placed between the matrix and the punch so that the tip of the punch fits into the recess marked by the core. Then turn the screw 1 handle 2 . The punch cuts into the metal and pierces a hole. The work requires a lot of force, so bears are used to pierce holes of small diameters and in sheets of small thickness.
Fig.2. Medvedka:
a – screw; 1 – screw; 2 – handle; 3 – bracket (housing); 4 – sheet; 5 – punch; 6 – matrix;
b – lever; 1 – screw; 2 – lever; 3 – bracket (housing).
The lever bearer is more advanced (Fig. 2, b). Medvedka has a screw 1 with left and right cuts. The lower nut of the screw is connected by a lever to the punch. As the screw rotates, the lever moves and the punch cuts into the metal, creating a hole.
Medvedkas are low-productive and are not used for mass production. Typically, hammers are used during repair work to punch a small number of holes.
Manual punch press. Manual lever press.
Manual punching and lever presses also operate on the same principle as the bearer. When punching holes in thin sheets, manual punching and lever presses can be compared to powered presses in productivity and efficiency.
Punch presses. Designs and principle of operation.
Driven punching presses for punching holes, used in repair shops, are manufactured welded, with welded cast iron or steel cast frames. Most often they are made double, because this way they are more compact and take up less space. A table made of steel sheets is installed in front of the punching presses; they serve as supports for the sheets being processed. Punching tables consist of a trestle with rollers. The rollers have slots for the vertical shelf of the corner. Punching presses are most often made with a belt drive from an electric motor and less often hydraulically.
In addition to punching presses, repair shops use automatic punching presses to punch holes.
To punch holes, each sheet is pre-marked or marked. On automatic punching presses, the sheet is divided into the required number of equal parts automatically. In this case, the straightened sheet is attached to a table that moves along the machine. The machine table can be stopped at any place by an automatic switch, which is driven by an electric drive.
To obtain the required number of divisions, only four corner points (on which the cores are placed) and center lines are applied to the sheet. The sheet is first installed with one corner core against the pointer associated with the indexing device, and is moved by the machine support to another corner point on the same center line, automatically determining the distance between them. Then the support returns to its original position, the divider is set to a certain number of divisions according to the number of holes required, and the machine pierces the holes.
The remaining holes on the sheet are also pierced.
Large holes (for manholes, pipes, etc.) in the middle of the sheet are formed by gouging. To reduce subsequent processing of the edge of the hole, the punch is given a rectangular cross-section with rounded corners.
The edges of the hole processed with such a punch have the correct outline without protrusions, do not require trimming with a chisel, but are only filed with a file.
Fig.3. Device for cutting holes for flame tubes.
Recently, large holes have been created by gas cutting. Pipe holes, the walls of which must have a smooth surface, are drilled using a special device (Fig. 3.).
A hydraulic punching press allows bending of sheets, strips and rods of thick-walled materials. The range of work can be expanded by purchasing additional equipment. This will allow you to cut ventilation louvers, punch holes of various diameters, process pipe edges and form metal blanks with high precision.
Hydraulic punching presses help
- significantly increase production volume,
- perform fairly complex work with metal,
- do not stop the production process when moving from the production of one workpiece to another.
Sahinler hydraulic punching presses: description
- In models HPM 65, 85, 115 and 175, the number indicates the force applied in the production of one part. The thickness of the material being punched depends on the value of this indicator.
- HRM 65, 85 and 115 DP have two independent work tables.
- HPM 65, 85, 115, 175 CNC are optimally suited for punching holes in precisely marked locations on sheet metal in X and Y coordinates.