22-05-2021, 09:53 AM
(21-05-2021, 07:49 PM)Tony Betts Wrote: interesting stuart.
we had taken into account modern cars having more jernals, also a smaller throw. and staggered jernal cranks.
here are the materials we were offered.
ASTM 4340 used for, engineering structual. used as require good toughness. high strength. as well as the important conditioning of large size. heavy machinery such as high load of axial, turbineshaft. larger than 250mm helicoptor rotor shaft. turbojet engineshaft, blade. high load of transmission parts. fasteners of the crankshaft, gear etc.
As above ASTM 4340 is equivalent to EN24T or 817M40T as the modern British Standard calls it.
(21-05-2021, 07:49 PM)Tony Betts Wrote: ASTM 4140 used for, many applications as forgings for the aerospace and oil and gas industries. a myriad of uses in automotive, agricultural and other defence industries, typical uses are forged gears and shafts, spindles. fixtures, jigs, and collars.
thanks tony
ASTM 4140 is equivalent to EN19 or 708M40 on the latest BS standard. It's used a lot by US manufacturers of forged high performance aftermarket conrods etc.
In general terms there's a lot of confusion over material specifications, not least because the UK, Europe and the US all use different nomenclature for engineering steels, but also because lots of people (me included) use the (obsolete since the late 1970s) EN naming system because it's easier to remember EN16T than 605M36.
Just to add some extra confusion, there is a newish BS EN system in place now (where the EN stands for Euro Norm) which was fun when I needed some bright round engineering steel from a stockholder who was initially convinced that I wanted a hot rolled steel beam.