What is Upsetting in Forging Die Design?

[hemal1972]

hello, expert people,
i am fresh mechanical engineer.
right now i am reading about forging die design.

i can not understand one term. i.e. upsetting or upsetter. please explain me about it.

 

[AlephZero]

It means shortening the length of a bar of material and increasing its diameter to make the required shape.

http://www.ustudy.in/node/2890

 

[peterlonz]

Very commonly you will see "hot upsetting" which is self explanatory.
Due to the extent of deformation resulting in most industrial upsetting processes, it is necessary to improve material flow by reducing material strength - achieved commonly by heating the material to above its plastic deformation range before upsetting.
The hot riveting process used widely in the early days of steel hulled ship construction is a good example.