Sheet Metal Processing Technology of CNC Turret Punching: Blanking and Forming Process

CNC punching machine sheet metal processing stamping is an important link in sheet metal processing, CNC punching machine can replace the processing capacity of the past 3 ordinary punching machines, greatly improving productivity.

CNC punching machine is a widely used machine tool, there are two types: single punch and turret. CNC turret punching machine integrates machine, electricity, hydraulic and pneumatic, and is a pressure processing equipment for punching processing and shallow drawing and deep forming on plates.

Features of CNC Punching Machines

The operation and monitoring of the CNC punching machine are all done in the CNC unit, which is the brain of the CNC punching machine. Compared with ordinary punching machines, CNC punching machines have the following characteristics:

1. High processing accuracy and stable processing quality;
2. It can carry out multi-coordinate linkage, can process parts with complex shapes, and can sit and shear forming;
3. When the machining parts are changed, only the CNC program needs to be changed, which can save the production preparation time;
4. The punching machine itself has high precision and rigidity, and can choose a favorable processing amount, with high productivity (generally 3-5 times that of ordinary machine tools);
5. The machine tool has a high degree of automation, which can reduce labor intensity.

The Role of CNC Punching Machines

CNC punching machine can be used for all kinds of metal sheet parts processing, can automatically complete a variety of complex hole patterns and shallow deep drawing forming processing at one time (automatic processing of holes of different sizes and hole spacing according to requirements, can also be used small punching die to punch large round holes, square holes, waist holes and curved contours of various shapes, can also be processed by special processes, such as shutters, shallow stretching, counterbores, flanging holes, stiffeners, imprints, etc.).

Through a simple combination of molds, compared with traditional stamping, it saves a lot of abrasive costs, can use low cost and short cycle processing of small batches and diversified products, with a large processing range and processing capacity, so as to adapt to changes in the market and products in time.

The typical processing technology of CNC turret punching machine mainly includes two types: blanking and forming.

First, the blanking process:
The blanking process, also commonly known as the material separation process, refers to the separation of the processed material under the action of external force, along the closed or unclosed contour and separation. Blanking can either be directly punched into finished parts, or it can prepare blanks for the next process such as bending, deep drawing, forming, etc. In general, the blanking process is mainly divided into the following four modes:

1. Single punching: single completion of punching, including straight distribution, arc distribution, circumferential distribution, and stamping of grid holes.
2. Continuous blanking in the same direction: using the method of partial overlapping processing of rectangular molds, long holes, cutting edges, etc. can be processed.
3. Multi-directional continuous blanking: the processing method of using small molds to process large holes can increase the flexibility of the machine tool and expand the processing range of the mold.
4. Encroachment blanking: the processing mode of using a small round die to continuously punch and process arc or spline curve with a small step distance is a common processing mode. Due to the use of small circles for fitting, the contour accuracy and cross-sectional quality are usually not high, and the blanking efficiency is low, when the punching size is large and the number is large, it is recommended to use a special punching mold.

Second, the forming process
The forming process refers to the processing method of the plate under the action of external force, the stress exceeds the yield point of the material, and a certain shape and size are obtained through plastic deformation, mainly including rollers, shallow drawing, flanging, bending, etc., the main forming characteristics of some typical parts and supporting molds. The forming process mainly includes the following

1. Single forming: according to the mold shape of a shallow deep forming processing method, using this forming mode, the shape and size of the mold must correspond to the characteristics of the processing, and the processing mode of the ordinary press is exactly the same, is a completely “rigid” processing mode.
2. Array forming: processing multiple different or the same workpiece processing method on a large plate.
3. Continuous forming: forming methods that are larger than the mold size, such as large-size shutters, rollers, rolling steps and other processing methods.

CNC punching machine processing technology characteristics

1. Easy to use, save mold opening cost:
CNC turret punch (NCT) is a collection of machine, electricity, hydraulics, gas in one of the pressure processing equipment, used for all kinds of metal sheet parts processing, can be on the plate a variety of complex hole processing, shallow drawing deep forming processing, can be one time automatic completion of parts processing.

CNC turret punching machine is one of the most vigorous in pressure processing equipment. CNC punching machine can not only automatically process holes of different sizes and hole spacings according to requirements, but also use small punching dies to punch large round holes, square holes, waist holes and curved contours of various shapes, and can also carry out special process processing, such as shutters, shallow stretching, counterbores, flanging holes, stiffeners, imprints, etc.

Compared with traditional stamping, CNC punching machine saves a lot of mold costs, can use low cost and short cycle processing of small batches and diversified products, has a large processing range and processing capacity, so as to adapt to changes in market and product demand in time.

2. High processing accuracy and stable processing quality:
CNC punching machine has high punching accuracy, small punching burrs, good flatness of the workpiece, less subsequent processing, low scrap rate, high forming quality, the dimensional accuracy of several punches can generally reach 0.1mm, and the dimensional consistency of the product is good.

3. It can process a single workpiece or batch processing of workpieces with group commands to improve productivity:
The processing speed of CNC punching machine is fast, and the stroke rate of general hydraulic equipment can reach 500~600 times/min, and some even as high as 900 times/min, and the maximum positioning speed can reach more than 100m/min. For large-size plates, it can basically be completed in one processing, unlike traditional processing, which requires multiple processes and processing on many different equipment.

4. When the machining parts are changed, generally only the CNC program needs to be changed, which can save the production preparation time.

5. Higher requirements for the quality of operators, higher technical requirements for maintenance personnel.