minimum teeth in socket for crowns

[gerod]

sprocket/corona for European roller chain. we talk about the minimum number of teeth in the socket: do you know the formula for calculation? I know it's a trivial question but I'm out of office and I have nothing under my hand except the forum.
a greeting

 

[luigi.paiano]

each chain has its own characteristics, usually you use about 18 teeth but you have to refer to the catalog! ! !
too low number of teeth causes wear and noisy operation!

 

[cacciatorino]

each chain has its own characteristics, usually you use about 18 teeth but you have to refer to the catalog! ! !
too low number of teeth causes wear and noisy operation!

the speech was related to resistance and not to good ingration. The question is, how many pinion teeth are distributed to the chain.

In my opinion, it is better to consider all the strength on the first tooth, which then is what happens when the chain wears a minimum.

 

[luigi.paiano]

then I understood wrong!the calculation should be done as you say with a suitable safety coeff. for wear!which can be high mlt(30-36)

 

[luigi.paiano]

However the message speaks of the minimum number of teeth in the socket.
as I said the minimum number should be calculated on the chain resistance with a very simple calculation on the shooting side of the chain itself.
there is a law, if you want I can expose you

 

[gerod]

we say that the minimum number depends on the pressure that the rollers exert on the tooth.
The more teeth I have, the better.
I am the interested user: Of course you cannot expose the legislation as a document if protected by copyright.
if you expose the concept or formulas then ok.
Hello and thank you.

 

[luigi.paiano]

the concept is this:
as another user rightly said the legislation is such that the number of pinion teeth affects only the safety coefficient, this because the design is a design based on the chain resistance and not on wear!
This is because it would be very complicated to perform calculations on it. So it was thought (intelligently) to perform resistance calculations and take into account a safety coefficient to indirectly include the calculation (not made) to wear.
Now wear is directly proportional to the relative rotation between the various chain links,this rotation is equal to 2pigreco/n where n is the number of teeth!so the more teeth you have the better!
Unfortunately, however, if you do not have the abachi of the building house you can do very little, I can only say that the safety coeff is usually worth 30-36 for n=8 and 8-15 for n=12 if you use zobel chains (for those rollers you could use a value between 6 and 25 depending on the peripheral speed)!
calculation is carried out on the free driver branch:
-calculum internal pin diameter knowing that qs/2 = (r/m)(pigreco d^3)/32,where q/2 is the traction of platelets,s is the thickness of platelets,r is the tensile strength,m the safety coefficient before said.
- plate number plate n:
q=ns(d-d) where d is the outer diameter: if I am not wrong d=d+s;
-refer that q/(nsd) is less than 10 kg/mm^2;
do this you're done. Be aware that the other chain sizes are based on d, if you want I can tell you.
I apologize if I have been unprecise, please note that this is a maximum dimensioning.It is also a didactic method, so it is not the bible

 

[gerod]

Well, I have to say that to be a postgraduate student, you seem prepared to me.
Congratulations.
Actually, I just had to prove that the choice of a chain transmission was wrong.
Of course, we can do a treatment on resistance and then we have to put the effort.
As a rule, the chain is chosen according to what the manufacturer tells you, or in the catalogue.
then, to avoid breaks for wear / fatigue do your nice maintenance plan and, in the case of lifting chains (my was one of these) you must check them every 3 months, as imposed by Legislative Decree 81/08.
the problem that I found was precisely to have a corner of hug of 90° and especially the chain always worked on the same shirts.

I won: they went to hydraulics!
Hi.

 

[luigi.paiano]

thank you for the compliment hi!