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standards of reference wheels dentate

Mattymecc

Guest
Hello everyone, it is the first time I write on this forum, I am a student of a technical institute, I write this 3d since in the study of the dense wheels I have arisen a doubt: for the sizing we have been told to use the formulas of lewis (for the bending) and those for the surface pressure sizing of the tooth, the manual of mechanics of the hoepli, while for the verification I did not understand how it proceeds, I have seen that there are various norms that can be/must follow, the uni 8669 (reported in the manual) and the iso 63wis, but also suffice with I have tried to read various discussions but I find it unclear the procedure of verification, perhaps for my inexperience. thanks in advance
 
Bye. The problem is easier than you think.
dimensioning: method to determine a priori a possible size and preliminary parameters. you can use any method. randomly shoot, use lewis, use hertz, use my curves (which I talked about everywhere).
verification: Once you set the data you should see if the teeth last or break. Here comes the rules. iso 6336 is the most comprehensive international reference standard for cylindrical wheels. However, you can also use the din 3990 even if you stopped and lost the last evolutions or you can use the uni 8862 that is experimental but still in 1987. There are also American standards anxious/agreed 2001-d04 which are a bit the primordial of the calculation of gears with some considerations but no longer developed in detail.
a little depends on the state of verification of gears and a little what you want to verify.

students often go into crisis because they teach him two formulas and make him believe that lewis and hertz stick to determine the ability of a gear... .not so because there are a lot of parameters that come into play: lubrication, surface finish, number of cycles, material hardness, type of treatment etc.
 
Good morning, thank you for the information you gave me, have made me clear in a simple and exhaustive way a couple of months of lessons and formulas. Would you know where I can find some dispenses explaining the application of the rules you mentioned or the rules themselves? Thanks again
 
If you are a student the rules you can take them free of charge thanks to the university (surely your has a convention, they will probably be in English but it's not a problem, you will find the English version with a measuring unit you). the norms just read them that explain everything, how to do the verification, how to control the values, they are error-proof.
 
I thank you for the information but I am a student in an industrial technical institute. ...
 
as the internal search of the forum, which few use, is a bit dispersive do a search on google inserting this string into italics site:cad3d.it "iso 6336"site:cad3d.it specific searches carried out only in that specific site
"Iso 6336" research specification exactly this text; removing quotes will also be returned pages where only the word iso or only number 6336 is present. It goes as if without the space between the two words you could have other results in case the norm had been written all attacked, as sometimes happens.
 
Excuse me if I break up again, online and here on the forum I looked at some things on the norms you have spoken about, and I have seen that there are a lot of coefficients and factors that do not always understand how they are calculated, usually in the professional field the checks are carried out by hand or with the use of programs? the dimesionment instead, what is simple? thanks to all in advance
 
Mattymecc said:
Excuse me if I break up again, online and here on the forum I looked at some things on the norms you have spoken about, and I have seen that there are a lot of coefficients and factors that do not always understand how they are calculated, usually in the professional field the checks are carried out by hand or with the use of programs? the dimesionment instead, what is simple? thanks to all in advance
Click to expand...
at industrial level, each company has its own calculation tools. They are usually excel sheets where, depending on the ability of those who prepared it, there is the system to measure but above all to verify.
who does craft gears, uses kisssoft or equivalent programs, very specialized, that work only according to the norms and in a quite automatic way propose solutions both for dimensioning and verification.
if you take the iso6336 is not very complex to use, as long as you know all the geometry formulas that however is the basis of everything. you need to work with profile shift and other things.
to start it better you will make the basis with good books, like the three volumes of niemann that I have quoted many times just for the gears.
to help you can also use the khk gear guides that are made very well and to have all the geometric parameters are the best available notes.
 
hi, remember that it depends largely on what you are verifying and the final purpose of your work, one thing is a gear of a differential of a car, another one of an odometer or a coffee grinder. .you should not always go beyond certain computational limits,otherwise you should do the fem analysis and apply the ntc also to the carter of the motor rooms and dimensional all the washers of the plant :d .. said that lewis and hertz constitute a good starting base .. then for those who start from scratch the guides of the khk gear are really done well, as they have suggested ..to every good study;)
 
First of all, thanks to all for the answers, I was useful to have an idea of how, practically, in the companies the design takes place. I will now study the guides of the khk gear, and I will see to get niemann. other question: what standard do you refer to?
 
As for the conical wheels it starts with 2003-b97 or iso 10300 more complete.
a book that is good for making an infarination, in Italian, free is the manual of the driver of the bonfiglioli. I've already talked about it in other posts.
 
There are many interesting conversations, where in my interventions I explain more or less what you asked the first post. qui You find it.
there are then many projects solved, studied and analyzed, like this....qui....opture qui.
There is only the embarrassment of choice. seek baby and discover a world.
there are also examples and drawings of some gearboxes as qui...and especially qui.
If you have some time I recommend you to run our forum well because it is a mine of information.
 
I thank you again mechanicalmg, I looked a little around, and I already found the manual of the bonfiglioli, which I am beginning to read, instead of the manual of the khk gear, which is in English and it turns out complicated. I would have the intention to create a spreadsheet, after studying how to extract coefficients with the bonfiglioli manual, only that of excel I barely have the basics. would you have some guidance to recommend? and moving profile into what is it and when using?
 
Mattymecc said:
I thank you again mechanicalmg, I looked a little around, and I already found the manual of the bonfiglioli, which I am beginning to read, instead of the manual of the khk gear, which is in English and it turns out complicated. I would have the intention to create a spreadsheet, after studying how to extract coefficients with the bonfiglioli manual, only that of excel I barely have the basics. would you have some guidance to recommend? and moving profile into what is it and when using?
Click to expand...
I'm glad you're adventured in this world of gears.
profile shift is a modification of the standard tooth shape and serves mainly for two reasons:
- increase the tooth base for gears with few teeth to eliminate the undercut and then give a very robust base
- change gears to reach the desired interest

secondary but importantly, the profile shift leads to a pair of gears to:
- different noise
- relative creeping speed equal to or different
- contact pressure equal to or different

profile shift we have treated it several times on the forum. on khk gear find the formulas step by step to have consistency of gears. on other books and manuals the thing is dispersive and there are not all formulas. on the niemann instead it is explained well to what it is necessary to move profile.

As for excel we say that if you do not subscribe to vba programming it is all simple with formulas, with formula guide and some tutorials. you can add some button to make choices from a list and then create a small database of materials or options from which to fish. remember that lists, if you use the function =search(what;vector search;vector result) must be placed in alphabetical order for the search column.
 
Thank you, excuse me if it is the umpteenth question, I wanted to ask you if the method c of iso 6336 is the one normally used or if others are used. the method is good for all gears?
 
Mattymecc said:
Thank you, excuse me if it is the umpteenth question, I wanted to ask you if the method c of iso 6336 is the one normally used or if others are used. the method is good for all gears?
Click to expand...
Don't worry, it's normal to ask if you want to know... one thing not to give me her please.
the b method is normally used. the method is often derived from b with simplifications.
all methods are valid in their field of application....and you have to read all the rules to understand exceptions.
 

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