Jul 13,2022
Due to its inherent advantages, CNC machining has become widely used in various manufacturing industries. Because of its benefits, CNC machining has become commonplace in multiple manufacturing industries. CNC machines may execute machining operations such as turning, milling, drilling, prototyping, etc.
It is capable of performing all of these techniques fast and with ease. These machines provide precision and necessitate accurate measurements, materials, and other specifications. Material selection is an essential component of every manufacturing process, but engineers and product teams must be cautious about CNC machining.
Because this procedure works with a wide range of materials — from metal to fibreglass to wood — it's simple to choose a suitable material for the job but not the best.
The manufacturing process chosen is determined by the part's design and quantity. Many manufacturing processes are still used, such as CNC machining and metal stamping. In some circumstances, the superior production technique is obvious. However, it is necessary to determine which strategy is most appropriate most of the time.
A metal stamping machine is a machine that is used to mould metal sheets into 2D and 3D shapes, such as blanking and cutting in 2D and drawing in 3D. Stamping is usually done with the help of tools installed in a press.
A punch and die move closer to the blank, stretch, and bend the sheet metal to achieve the desired shape. Piercing can be done at the same time if necessary. Sheet metal is continually supplied to the punch and die in high-volume processes to get the desired form using modern tools in several phases. As a result, we'll look at the pros and Cons of selecting the best method for your volume requirements.
Several different metal stamping techniques are used for other applications. Some instances are provided below.
This metal stamping technology divides the process into a succession of stations, each with its purpose. The stock strip transports the component from one station until it is completed and removed.
The initial metal strip makes its way into the die press from its coil. The metal then slides horizontally over each station from there. The part travels to the next station as soon as the necessary bend, punch, or cut is finished.
Because the part is still attached to the metal strip while being modified, every movement must be precise. This accuracy and precision ensure that the final product is valid and usable.
Progressive die stamping is a cost-effective approach to producing large parts, appealing. The die last a long time, and the operation can be repeated as many times as needed. This types of metal stamping also generates tiny scrap.
Transfer die stamping is another sort of metal stamping. It's similar to progressive die stamping, except instead of an automated strip, the part is moved from station to station by a mechanical transport system. Stamping aids in producing pieces that must be free of the metal strip during the stamping process.
It may require a single die or numerous dies or equipment to build a makeshift production line.
Transfer die stamping is an excellent alternative for production because of the cheaper tooling costs. Cut-outs, ribs, knurls, threading, and piercing holes are possible. It implies no additional operations are required, further lowering costs.
Agriculture, automotive, locomotives, electronics, medical, recreational vehicles, and other uses transfer die stamping. It helps produce more oversized, thicker items that may require many presses.
Fine blanking, also known as fine-edge blanking, is another type of metal stamping. Other metal stamping procedures cannot achieve flatness and a full-sheared edge like this metal stamping can.
This method employs cold extrusion and is a one-step procedure, resulting in decreased production costs.
A hydraulic or mechanical press, or a combination of the two, is commonly used for fine blanking. In the delicate blanking procedure, there are three distinct movements:
1. Use the clamp on the workpiece to secure the workpiece or work material.
2. The blanking operation is now complete.
3. The completed component is expelled.
It's possible; that the product must make complete contact with the edge's surface.
Fine blanking is ideal for this type of manufacture since gears require flatness in particular places, and they must fully engage every tooth to be functional.
Four-slide stamping, also known as multi-slide stamping, uses four tools to form the object into the desired shape simultaneously. Each shaft quickly bends the metal sheet as it passes through the four-slide.
It's great for making things with complex bends or intricate cuts. While conventional metal stamping processes form the metal item with a vertical slide, four-slide stamping shapes the metal piece with four different sliding tools.
Four-slide stamping uses exceptionally productive and straightforward tool slides, making it a perfect method for manufacturing complex or multi-part bends, including bends more significant than 90 degrees. It can complete multiple bends, punches, folds, or cuts.
Metal stamping is a low-cost production method. Because it is generally less expensive than other ways, it is perfect for small enterprises. Many people assume that it is also less costly because it does not require moulds or tooling to make the component or part.
However, sheet metal stamping does not require tooling; it can be more expensive because you must pay someone to do the planning and design work rather than using standardized equipment.
Metal stamping can simultaneously produce hundreds of similar pieces, allowing industry to make massive goods while maintaining high-quality standards. This advantage is most useful for simply shaping pieces that do not require much customization.
Sheet metal stamping tooling consists primarily of shear, punch, and bending dies, making it straightforward. Employees who are already familiar with basic machine operations will most likely stamp sheet metal without difficulty.
Sheet metal stamping is a versatile manufacturing method for producing parts in various shapes and sizes. It's a beautiful option for companies that need to generate large quantities. Furthermore, stamping can be used to make both basic and complex parts.
The following are essential pros and cons of using a metal stamping machine:
Sheet metal stamping has a high scrap rate by definition. To work correctly, stamping dies require flat, smooth sheet metal surfaces. Because this production process necessitates big metal sheets, you risk discarding many minor parts that do not fulfil quality standards if the sheet is not flat. When you manufacture in large quantities, you produce more scrap.
Metal stamping techniques are appropriate for simple machine parts and require minor customization. Manufacturing is economical and straightforward, thanks to the simple shapes and curves. However, you can expect to pay more when utilizing this technique on custom projects or highly intricate parts because of design fees and added labour charges.
Sheet metal stamping is terrific for making simple pieces, but it may not be the most excellent solution if you require more complexity or detail. Sheet metal stamping stamps cannot readily generate tight curves or intricate details, so you may need to explore other options if your item is complex.
Sheet metal stamping is time-consuming and labour-intensive compared to other manufacturing methods. If you need many things created fast, this can be a considerable disadvantage.
CNC metal machining processes include:
1. Cutting metal from the tube.
2. Solid bar.
3. Billet.
4. Casting to achieve the desired shape.
The workpiece is fixed in most machining processes, and different operations are done. Milling, for example, is a straight-plane cutting operation, whereas grinding and turning are cylindrical processes that produce cylindrical geometries on the workpiece.
CNC (Computer Numerical Control) is a term that refers to controlling machine tools. Each motion axis in a CNC machine is controlled by a spindle that is directly influenced by motors that are limited to following the CNC programme list's instructions. As a result, you may easily shape a solid metal block into the necessary geometry.
Because of their wide range of uses, CNCs have become indispensable in almost every industry. In a similar vein, below are some of the significant benefits of CNC machines:
1. CNC machines are capable of creating complex 3D items with strict tolerances.
2. The sort of metal that can be machined with CNC has no limitations. However, some of them may necessitate specific cutting instruments and conditions.
3. Cutting Tools used in CNC machining are often consumable and less expensive than tools used in other manufacturing processes such as metal stamping.
4. Throughout the process, the surface finishing is unaffected.
On the other hand, CNC machining has the following drawbacks:
1. The material efficiency or utilization is low.
2. CNC machining may have a low production rate depending on the material removal rate.
3. Machined parts may require additional machining before they can use them.
Four crucial factors need to be kept into account:
1. Quantity required
2. The component's geometry
3. Precision and tolerance levels
4. The material's nature
As a result, these are the most critical considerations to consider when deciding between metal stamping and CNC machining. Let us now discuss the significance of these aspects.
Metal stamping is a considerably faster technique than CNC machining. Hence it is used to produce parts swiftly. It is possible only when the press is ready to run, and the tooling size and design are of moderate complexity. Otherwise, metal stamping can take a long time, up to several hours.
As a result, metal stamping might not be the best option. Though the footprints and part programme are produced using the CAD file, CNC machines may have a faster setup time. Metal stamping tooling costs are often greater than CNC machining tooling.
Metal stamping tools are made from complex steel grades that take weeks to create. However, CNC machine tools often employ disposable cutting inserts stored on a rack and ready to use.
It is unable to stamp intricate designs. They can't stamp cylinder heads, engine blocks, housings, or valve bodies since they are perfect. Achieving specified dimensions, tolerances, and surface finishes may require additional machining processes.
CNC machining, on the other hand, has decreased part geometry constraints. However, the cutting tool must always fulfil the features to be machined.
Metal stamping has increased product uniformity thanks to the precision of stamping tools and material quality control. Tolerance, though, continues to be a challenge. On the other hand, CNC machining is capable of handling tighter tolerances.
When stamping, metal should be flexible or malleable. Although it can imprint some metals after heat treatment, many are not suited for stamping due to their excessive hardness.
Furthermore, the thickness of the sheet can rule out metal stamping as a viable option because bigger sheets may necessitate greater force for deformation and piercing. Large-scale machinery and sturdy tooling are required at the end.
Working with thin metal sheets is a challenge for CNC machining. It is the situation because the clamping loads cause deformation in the delicate sheet metal parts.