Fractured connecting rods

[Vulnavia]

Learned something new today. When building the new corvette engines, the connecting rods big end is "1" piece.
It is then placed in a machine that "fractures" the big end so the technicians can align them with precision.
Who'd a thunk it?

Will

[Rick Kirchner]

Been going on for about 20 years. IIRC they use powder met in the production of the forging, so you get a grain structure that works for this.

But then again, I only impersonate an ME every now and then, and occasionally sleep at a Holiday Inn.

[Charlie Schmidt]

https://www.cycleworld.com/2014/05/2...ing-rods-made/

[APEowner]

The first time I ran across that was in a 2 stroke outboard engine built in the '50s.

[Mark_Silverberg]

First automotive application was the Ford 4.6 l Modular engine in fall of 1990 for the 1991 model year. This was also the first powdered metal connecting rod. The fracture concept was to provide lateral location of the rod cap without having to sleeve or pin the caps. It also eliminated a machining operation.

[Vulnavia]

Had no idea they have done this for that long. It surprised me at first, but with the replies I did a little net surfing to learn more about the process and reasoning. Always happy to learn about this kind of stuff. ( the rods were a pressed powdered steel).

Thanks,
Will

[APEowner]

Had no idea they have done this for that long. It surprised me at first, but with the replies I did a little net surfing to learn more about the process and reasoning. Always happy to learn about this kind of stuff. ( the rods were a pressed powdered steel).

Thanks,
Will

They've been around for so long that when I first saw them I had to go to a library and read an SAE paper, printed on actual paper, when I wanted to research them.

[nwp]

Learned something new today. When building the new corvette engines, the connecting rods big end is "1" piece.
It is then placed in a machine that "fractures" the big end so the technicians can align them with precision.
Who'd a thunk it?

Will

VW/Audi have been doing it ages ago, really old school now.

[JSM16]

I used to work for Ex-Cell-O machine tools north America. We built rod cracking machines for the automotive industry. It's quite the process first the rod gets broached 45° on the I.D. at the intersect point, then it transfers to the fracture station. The fracture station uses high speed high pressure hydraulics to stretch the rod causing the fracture and separation.