Forging is a metallurgical process that involves hammering or pressing metal together to deform and manipulate it into a desired shape. There are so many examples of forging, and it’s not always easy to understand which one is the best option for you. Below I have detailed a few of the significant benefits to upset forging and whether you should choose to use the better forging process.
Many industrial, commercial forging operators specialise in upset forging. But what exactly is upset forging, and what are the advantages of upset forging over other manufacturing techniques.
So what exactly is upset forging?
Upset forging, otherwise known as hot heading or drop forging, is similar to closed-die forging in that it uses the pressure from two presses closing together to mould a metal structure. Upset forging can be done through both the hot forging and cold forging process.
Basically, upset forging is a metallurgical process that uses high pressure to deform metal into high-strength parts of various sizes. For longer shapes, where only one end of a component needs to be forged, this forging method is perfect.
How does upset forging work?
These components are manufactured on a horizontal mechanical press. The dies are split to enable the metal to pass through the mechanical press, and a third die attached to the header provides some of the forming force.
The stress produced on one end of the material being pushed into is utilised to change its shape. This is done by applying pressure to two opposite sides of the material. The material itself can be forced into a larger or smaller diameter. Of course, the press is capable of producing a variety of sizes. The cross-sectional size of a bar can be increased using this method, either at the ends or at any point along its length. To monitor size and form, special upsetting machines with closed dies are used.
In most forgings, an upper die is pressed against a heated workpiece held by a lower die that remains stationary. Drop forging refers to the method of dropping the upper die or hammer.
Advantages of upset forging:
Strength: Much like traditional forging, upset forging utilises all the benefits of the forging process; that is, greater strength is retained within the forged product. This is due to the condensing of the metallic bonds in order to maintain tensile strength and durability. As compared to parts machined from billets, upset forging gives greater strength because the material grain flow is tailored to the component’s desired shape.
Lower risk of fractures at joints:
In comparison to welded fabrications, there is a lower risk of fractures at joints because the upset process actually bonds the two components together.
Where the material size is decreased, no stress areas are produced:
There are no tension areas when the material size is reduced due to the condensing of the workpiece rather than the cutting of the metal often seen in the casting process.
There are no concerns about the porosity or brittleness of the forged material:
Because forging is the most durable method of manufacturing metal products, the risk of brittle material is eliminated as forging works to fortify the product rather than weaken it. In terms of porosity, forging compacts the ions of a metallic bond together and therefore allows the metal to form as a shape without stretching and exposing a porous surface. The upset forging process not only makes products smooth but decreases the risk of a brittle finish.
Resistance against impact:
The fact that intensive impact is applied throughout the manufacturing process means it is more capable of withstanding pressure in the long run, as the product is manufactured specifically to withstand high pressure. The grain flow will have optimum strength and resistance as the part is forged.
Piercing and Trimming Operations: This helps to reduce part weight and eliminates machining operations.
More Cost-effective than other forms of forging:
As upset forging requires fewer operations, this can make it more cost-effective. Not only this, but because there are lower scrap costs, upset forging can save you a significant amount of money in the long run.
Examples of Application:
The following are some main examples of items that would be ideal for the upset forging process:
- Artillery shells
- cluster gear blanks
- heads of bolts
- cylinders for radial engines
It’s a simple enough concept, but mastering upset forging takes time and experience. When you’re looking for a forging manufacturing specialist to manufacture your specialist parts, make sure to choose a proven, experienced operator.