Forging

Forging Overview

Metals, in their raw form, are of less importance. You need to process them so that they can be put into proper use. The processing can change the physical structure of the metal or even the visual aspects of this material. Forging is just one of the industrial activities that are carried on metals to make them more relevant.

Do you want to learn about forging and its importance? In this guide, we are unraveling everything that you should know about forging.

What is Forging?-Definition

Forging is an intricate manufacturing process that entails shaping the metal using a series of localized compressive forces. These forces are delivered blow by blow utilizing a hammer or even a die. Forging is sometimes referred to as impression die forging, closed die drop forging, or Near-Net.

These forces will eventually change the shape of the metal even as it remains in the solid-state. This is unlike other methods such as casting whereby the metal is first turned into a liquid form before its shape is changed.

Forging is often categorized depending on the levels of temperatures that are used for the process. For that reason, we have cold and hot forging. For the hot forging, the piece of metal is heated before its shape is changed.

There are different types of metals that are subjected to the forging process. However, each metal is handled in a unique way and this explains why there are different types of forging processes. Each process is well-curated for a particular type of material.

It is also critical to note that forged metal parts vary in terms of weight. Some metals can be heavy, while others are very light.

Forging has been used for many years and it enjoys a wide range of applications in the metal industry. Many products have been obtained from this metal processing technique.

Products of forging include; kitchenware, hardware tools, weapons, cymbals, jewelry, among others. There is no doubt that forging is a process that has a major impact on the modern world.

History of Forging

History of Forging  

http://www.steelforging.org/the-history-of-forging-process/

Forging is one of the oldest known processes for metalworking. In the ancient days, forging was performed by a smith using simple tools such as hammer and anvil. It was quite cumbersome and time-consuming.

The introduction of water power to the assembly and dealing with metals in the 12th century allowed the utilization of large-sized hammers or power hammers. This increased the quantity and size of metals that would be produced and forged.

The smithy or forge industry has evolved over centuries to become a facility with engineered processes, tooling equipment, raw materials, production equipment, and other range of products that are designed to satisfy the high demand of metals.

In modern times, industrial forging is completed with either with presses or with hammers powered by compressed gas, electricity, hydraulics, or steam.

These hammers tend to have reciprocating weights within thousands of pounds. Smaller power hammers, 500 lb (230 kg) or less reciprocating weight, and hydraulic presses are common in art smithies.

Some steam hammers are still used to date. However, most of them became obsolete with the innovation of the more convenient, power, and electricity sources.

Advantages and Disadvantages of Forging

Should I use the forging process to shape my pieces of metals? This is a question that many people tend to ask.

Like many other metalworks techniques, there are advantages and disadvantages of forging. We are going to look at the two sides of the coin so that at the end of the day you can make an informed decision with regards to this process.

Advantages of Forging

Here are the main benefits of forging process:

Results to strong machined parts: When compared to the casting process, the parts from the forging process are definitely stronger. Well, how is this possible? With the forging process, the internal grain of the metal will realign itself to be in unison with the shape of the metal. This results in the improved strength characteristics of the metals.

forging process

Image showing the grain conforming to the forging process source: https://www.whtildesley.com/processes/advantages-of-forging

Lower cost: In terms of the cost, forging is still cheaper than metal casting or even fabrication methods. There are fewer requirements for forging as compared to the casting process.

Unlike the popular assumption, the tools required for the forging process are also cheap. This ultimately means that you will pay less money for the overall forging process.

Also, choosing the right forging company in China will result in low cost o the process.

Structural integrity: Structural integrity is the ability of the metal to perform its job without any structural defects. Forging eliminates the cases of common metallurgical defects such as porosity and segregation of the alloys. These are common issues with metal casting.

The resultant effect is a uniform metal outline and minimized scrap.

Also, forging eliminates the risk of porosity. The metal won’t has any cracks that can compromise its integrity.

Allows for post-forging machining:  Forging process makes it easier for the execution of the post forging machining. This is because the process results to minimal voids, cracks, and porosity. The after machining process will be more accurate.

Shorter cycle times: How long does the forging process take? Although there are no defined cycle times for forging, one thing that is clear is it takes a shorter time than the casting process. However, the time taken will depend on the shape and type of metal.

Allows for maximum flexibility: Metal forging gives manufacturers plenty of opportunities to explore. For instance, the method can be used for shaping metals with complex designs.

Also, you can use forging to shape metals with different weight and strength.

In terms of production capacity, forging can be an ideal method for both small scale and large scale production. Any volume of metals can be subjected to the forging process. The same applies to the sizes of metals. Both large and small-sized metals can be shaped through this process.

Disadvantages of Forging

The main problem with the forging as a method for metal manufacturing is the high capital investment. The machinery and tooling required for the process are quite expensive. Also, forging can only be monitored and executed by well-trained technicians.

The good news is you can avoid the issue of cost by choosing affordable metal forging manufacturers in China. With them, you will cut down the cost by a significant margin.

Another problem with forging is the negative environmental impact that the process can have. The process is always associated with constant noise and vibrations. People living in the surrounding areas may find this uncomfortable.

However, this issue can be deal with by using special buildings that are noise-proof.

On the other hand, there is minimum wastage of the material through forging.

What are forging defects?

Although metal forging is curated to produce the best results, some defects are associated with it. Some of these defects include;

-Unfilled section

-Scale pits

-Die shift

-Flakes

The best forging companies are always dedicated to eliminating or minimizing the impact of these forging defects.

By comparing the advantages vs. disadvantages of forging, it is crystal clear that there more to gain from the process.

Types of Forging Process

  Types of Forging Process

Image source https://www.ispatguru.com/processes-for-forging-of-metals/

There are different types of forging processes that can be used on metals. Let’s look at each type and its importance:

As we had stated earlier, forging is divided into two broad groups. These are Hot and Cold forging.

Hot Forging

Hot forging is where the metal is heated beyond its normal recrystallization temperature. For most metals, the temperature can be as high as 2000 degrees Celcius.

One of the chief advantages of hot forging is that it decreases the temperature required for the metal forging. In fact, the excess heat generated from the process is used to enhance the strength and ductility of the metal.

Also, products that are created from hot forging tend to have a uniform temperature consistency.

Cold Forging

Cold forging is where the process is carried out under the normal room temperature. This means that the temperature is way below the recrystallization temperature of the metal.

The main advantage of cold forging over hot forging is the quality of the metal produced. It is of a higher standard, uniform, and results to a smoother surface finishing.

However, this method is not ideal for some hard metals such as steel. They are too strong to be shaped under normal conditions. Powerful and expensive equipment may be needed to perform cold forging.

Categories of Forging Process  

Beyond the cold and hot forging, the processing is further subdivided into smaller categories. These are;

Press Forging

Press forging works by slowly applying endless pressure or force, which varies from the near-instantaneous impact of drop-hammer forging.

The period of time that the dies are in contact with the workpiece is measured in seconds (as compared to the milliseconds of drop-hammer forges). The press forging operation can either cold or hot.

The main advantage of press forging, as compared to drop-hammer forging, is its ability to deform the entire workpiece. Drop-hammer forging will only cause deformation only on the surfaces of the workpiece in touch with the hammer and anvil. Otherwise, the workpiece will remain relatively undeformed.

Another advantage of this method includes the knowledge of the new part’s strain rate. By controlling the compression rate of the press forging operation, the interior strain is often controlled.

Closed die forging

Closed die forging is also known as impression die forging. Its working mechanism depend son the molds to transform the shape of the metal.

The molds are attached to the anvil while the hammer forces direct the molten metal to flow through the cavities of the designated die.

The shape and the geometries of the metal are formed after several strikes. This type of forging is ideal for producing complex shapes and geometries.

Closed die forging is also known for producing strong metals. This explains why most automotive parts are shaped using this method.

The main disadvantage is the equipment that is used for closed die forging is quite expensive.

Open die forging

This method of forging is used on flat dies that don’t have precut profiles. It is also known as smith forging. The open die forging method restricts the movement of the metal flow to all the regions except to the zones that are in contact with the die.

The movement of the workpiece should be well done so as to achieve the best results. The metal should also be heavy and be relatively long.

Open die forging is mainly used for shaping ingots before they are subjected to the secondary shaping processes. Some of the advantages of open die forging include an elaborated grain flow, minimized voids, and high resistance to fatigue.

Materials and Products of Forging

What Metal is the Best for Forging? This is a question that you are likely to ask when inquiring about the best materials for forging.

Any metal can be subjected through a forging process. However, there are metals that are commonly forged. They include;

-All types of steel

-Carbon

-Aluminum

-Titanium

-Copper

-Alloys such as cobalt, molybdenum, nickel

-Brass, among many others.

Do you have any metals that you would want to be forged? Get information from the best metal forging companies in China.

In terms of the application, forged metal parts are used in any application that requires the use of well-shaped metals. These include automotive, cookware, jewelry, building and construction, electric and electronics, among many other products of forging.

Conclusion

Now that we have covered almost all the basics of forging, the next step is to seek this service. You should consider seeking this service if you have metals that need to be shaped before being used for different products.

At Roche Industry, we provide accurate forging services in China. We have the best people and equipment to do the job. Simply contact us, and we will answer everything that you need to know about forging.

References

Advantages of forging https://www.whtildesley.com/processes/advantages-of-forging

Different forging defects https://studentlesson.com/forging-defects/

Forging wiki https://en.wikipedia.org/wiki/Forging#Press_forging