How to Design a Two-Stage 200 kW Helical Gear with 1:8 Ratio?

[Asif221]

Hello,
I want to design two stage 200 kilowatt helical gear. Ratio that I want is 1:8.
Input rpm 1250 with medium shock.
Can anyone help me.
Or suggest me any free software where I can get gear design.

 

[anorlunda]

What research did you do before posting your question?

I did a quick search and found lots of free gear design sites. https://duckduckgo.com/?q=gear+design&ia=web

For us to give guidance on your design, we would need a lot more information on your goals and requirements. Your best approach is to use Internet searches first.

 

[jrmichler]

This is beyond what can be done with an internet calculator. Start by buying a copy of Practical Gear Design by Dudley. That may not be the exact title, but it's close. Read the book from cover to cover until you understand how and why to adjust tooth geometry to get the maximum efficiency, why a reduction gear set uses different tooth geometry than a speed increase gear set, until you understand how do design a lubrication system for this gear set (oil bath is probably not good enough), how to design an oil cooling system, tolerances, effect of shaft and housing deflection, etc. Then, and only then, buy a copy of Kisssoft gear design software.

If your reading convinces you to hire a gear design expert, then you understood the book. If not, go back and read it again.

Your profile indicates that you are a student, in which case this appears to be homework. In that case, go to your library, find the book by Dudley, skim it from cover to cover, then go to your undergrad machine design textbook, and go through the procedure there. Just recognize that if somebody actually tried to build that gear set, they would learn some expensive lessons.

 

[berkeman]

If your reading convinces you to hire a gear design expert, then you understood the book. If not, go back and read it again.

Classic!

Just recognize that if somebody actually tried to build that gear set, they would learn some expensive lessons.

Yeah, 260 horsepower is a handful to manage!

 

[Asif221]

hello,
i have a gear box but i don't know its power i thought that it would be approximately 200 kw. by the way suggest me with below mentioned specs of gears.
1ST STAGE
PINION TEETH-20, HELIX ANGLE-8 DEGREE, MODULE-6, OUTER DIA-133, FACE WIDTH-8 INCHES
GEAR TEETH-50, HELIX ANGLE-8 DEGREE, MODULE-6, OUTER DIA-315, FACE WIDTH-8 INCHES
2ND STAGE
PINION TEETH-22, HELIX ANGLE-11 DEGREE, MODULE-10, OD-244
GEAR TEETH-70, HELIX ANGLE-11 DEGREE, MODULE-10, OD-733
ALL GEARS ARE HARD UPTO 55-60 HRC AND MATERIAL IS 8620.

SO CAN ANY ONE TELL ME THAT HOW MUCH POWER THIS GEAR BOX HAS OR HOW MUCH POWER CAN BE TRANSMITTED ON THIS GEAR BOX.

 

[berkeman]

hello,
i have a gear box but i don't know its power i thought that it would be approximately 200 kw. by the way suggest me with below mentioned specs of gears.
1ST STAGE
PINION TEETH-20, HELIX ANGLE-8 DEGREE, MODULE-6, OUTER DIA-133, FACE WIDTH-8 INCHES
GEAR TEETH-50, HELIX ANGLE-8 DEGREE, MODULE-6, OUTER DIA-315, FACE WIDTH-8 INCHES
2ND STAGE
PINION TEETH-22, HELIX ANGLE-11 DEGREE, MODULE-10, OD-244
GEAR TEETH-70, HELIX ANGLE-11 DEGREE, MODULE-10, OD-733
ALL GEARS ARE HARD UPTO 55-60 HRC AND MATERIAL IS 8620.

SO CAN ANY ONE TELL ME THAT HOW MUCH POWER THIS GEAR BOX HAS OR HOW MUCH POWER CAN BE TRANSMITTED ON THIS GEAR BOX.

Please don't post in all capital letters. It is considered yelling, and is against the PF rules. I can see how some of the lines are maybe copy-paste information that may have already been all caps, but you also wrote in all caps for part of that post. Thanks you for your consideration.

 

[jrmichler]

I once was discussing a gear with the gear expert that designed it. The gear was a heat treated and ground helical gear. The gear expert said that it was rated for 640 ft-lbs torque in that particular application. I asked what the torque would be if he redesigned the gear, keeping the size and dimensions constant. He started mumbling about alloy, double heat treatment, shot peening, and some other things. The upgraded gear would have been rated for 1140 ft-lbs torque, 80% stronger than the standard gear.. None of the differences he mentioned were detectable by simple observation.

That told me that attempting to reverse engineer a gear without knowing its detailed design and manufacturing procedure would be a hopeless task. As an example, look in your undergrad machine design textbook at the graph that shows gear velocity factor as a function of gear tooth tolerances and speed. The correct procedure to find the rating for an existing gearbox is to contact the manufacturer and ask them.

BTW, your title does not agree with your first post, which does not agree with your second post. You claim to be working on a master's degree. You are are asking for help from people with doctorates and people with several decades of experience. You are asking about a very expensive piece of equipment. A person in your situation should expect to spend a couple of hours putting together a coherent and well written request for information, not just bang out a demand for an answer before you fully understand the problem.

 

[Baluncore]

I want to design two stage 200 kilowatt helical gear. Ratio that I want is 1:8.
Input rpm 1250 with medium shock.

Is that a speed reduction of 8, or a torque reduction of 8; For 1250 RPM input, what is output RPM?

Power = Torque * RPM. It is torque that a gearbox is designed and specified to handle. Knowing HP or kW is meaningless without RPM or torque. If you know torque and RPM, the power can be computed. The RPM is limited by lubrication and cooling, it decides MTBF.

That told me that attempting to reverse engineer a gear without knowing its detailed design and manufacturing procedure would be a hopeless task.

I agree. Opening the box to look at the contents will give you the exact ratio but will only put you in the ballpark regarding torque and MTBF.

You can often better identify gearbox specifications by knowing the input shaft diameter and RPM.
Sometimes knowing the type of coupling helps.