material for reducing

[Gengis26]

Hello, guys.
is facing a small educational project for the examination of mechanical design.
I have to make a maximum sizing of a reducer.
the reducer in question will have to work on a stone crushing device.
I am currently designing dense wheels and transmission shafts, and I wanted to look for a material taking into account the fact that the reducer will have to work in a fairly stressed environment, where not much precision and silence is required, but reliability and durability.
Can you give me some tips on choosing?

Thank you so much!

 

[meccanicamg]

Bye. First of all, let us make a summary of useful things to keep in mind:

- first let's go look for service factors cataloguing on the tables to figure out what kind of oversized you have to do. molino and crushing class m (overloaded) if we plan to start up to 15 times per hour we have a first k1=1.1. evaluating that work 24 hours a day with an electric motor with strong shocks due to the stone we have a second coefficiene k2=2. therefore k=k1*k2=2.2 and is the value for which you have to ensure oversize

- steels for shafts and gears, since they are very stressed to say that you can very well use 42crmo4 uni en iso 10083 to be reclaimed eventually tempered in the tabs to increase the specific pressure resistance from shock to those trees that you can oversize without big problems and on the sides of the teeth continuously. use 17nicrmo6 uni in 10084 more hardened cementing to achieve high performance for the most stressed shafts and gears. when you audit according to regulations uni 8862 or iso 6336 of gears you will need to keep in mind that you have an adequate oversized factor. i.e. that at nominal power you will need to have a service factor and then oversize at least 2.2 or higher even in gear verification, or if you use the correct multiplied power k, you will have a factor of oversize gears greater than 1.

- as far as the case is concerned, I recommend that you use electro-welded plates in s275jr o s355jr and here possibly make a fem on the carcass as it is almost empirical and impossible to make resistance calculations on the case itself
- predict tempered tabs also in c43e/c45e if enough otherwise in c50e However induction hardened on active hips
- pay attention to carvings
- predict if possible a safety clutch system not to damage all organs if there was an anomaly on the plant

 

[Gengis26]

Thank you very much for the answer,
fortunately to intuition I have more or less anticipated everything you have recommended to me; the verification instead on the carcass and the possible friction system are interesting ideas on which to work, to be honest had not come to mind!
being, however, fundamental the materials for the general size and the resistance of the reducer, I am pleased to be on the right path.
I thank you again for the answer, while being a didactic dimension, I want to try to be as realistic as possible!