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Air Medal or two
Join Date: Jul 2003
Location: cross roads
Posts: 14,081
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Belt / pulley engineers
Is there a rule of sorts for power losses on a pulley?
I checked google for a hour.......sort of got lost...they did 90 deg turns...... Just pulley to pulley........ Is there A rule of thumb of sorts per belt? thanx!
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D troop 3/5 Air Cav,( Bastard CAV) and 162 Assult Helicopter Co- (Vultures) South of Saigon, U Minh Forest, Delta, and all parts in between |
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Get off my lawn!
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Use suspenders not a belt and your pants don't lose any power. For ultimate power use both a belt and suspenders!
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Glen 49 Year member of the Porsche Club of America 1985 911 Carrera; 2017 Macan 1986 El Camino with Fuel Injected 350 Crate Engine My Motto: I will never be too old to have a happy childhood! |
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Air Medal or two
Join Date: Jul 2003
Location: cross roads
Posts: 14,081
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wow........................This used to a place of great thought.
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D troop 3/5 Air Cav,( Bastard CAV) and 162 Assult Helicopter Co- (Vultures) South of Saigon, U Minh Forest, Delta, and all parts in between |
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Did you get the memo?
Join Date: Mar 2003
Location: Wichita, KS
Posts: 32,541
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You would have a coefficient of friction between the belt/pulley, which would be a function of materials, interface, and belt tension. That would be one way to calculate the losses, though guys that do it for a living probably have a more clever way.
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Registered
Join Date: Jun 2001
Location: Sweden
Posts: 5,911
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Rule of thumb:
1. V-belt will loose more than flat-belt. 2. The more "bends" you do the more power you loose.
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Thank you for your time, |
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Ayo Irpin, Ukraine!
Join Date: Mar 2004
Location: Santa Cruz, CA
Posts: 12,552
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For every 2 pulleys you lose 288.
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Harmlessly passing gas in the grassland away; Only dimly aware of a certain smell in the air |
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závodník 'X'
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OP - wide open that leads to a 1000 questions with a 10000 different answers. For example, cogged belt (as in an engine timing belt) vs. V type smooth vs. V w/notched....
For start > Belt Tension Theory: Factors Timing belts > http://apps.gatesmectrol.com/applications/doc/Belt_Theory.pdf
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“When these fine people came to me with an offer to make four movies for them, I immediately said ‘yes’ for one reason and one reason only… Netflix rhymes with ‘wet chicks,'” Sandler said in a prepared statement. “Let the streaming begin!” - Adam Sandler Last edited by intakexhaust; 01-07-2014 at 01:12 PM.. |
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Air Medal or two
Join Date: Jul 2003
Location: cross roads
Posts: 14,081
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V belts
this particular application runs about 7 pulleys engine, jack shaft, then sprocket 15 pound chain to a HUGE sprocket (to gear it all dwn) I can do this with one drive shaft, and a ring gear (ring and pinion type ) I am thinking this would be so much simpler get rid of a bunch of stuff
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D troop 3/5 Air Cav,( Bastard CAV) and 162 Assult Helicopter Co- (Vultures) South of Saigon, U Minh Forest, Delta, and all parts in between Last edited by afterburn 549; 01-07-2014 at 02:10 PM.. |
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Navin Johnson
Join Date: Mar 2002
Location: Wantagh, NY
Posts: 8,808
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Took a few seconds to find this
TUTORIAL – PULLEY DRIVE SYSTEMS It is not a simple exercise, It is a dynamic system with many variable..Your going to need some good math skills, DiffEq's etc.. This is also some light reading on the subject
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Don't feed the trolls. Don't quote the trolls ![]() http://www.southshoreperformanceny.com '69 911 GT-5 '75 914 GT-3 and others Last edited by TimT; 01-07-2014 at 02:15 PM.. |
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Air Medal or two
Join Date: Jul 2003
Location: cross roads
Posts: 14,081
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WOW
and thanx Some one was a genius to come up with this belt system..... I think one more tweek is to get rid of it all togther
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D troop 3/5 Air Cav,( Bastard CAV) and 162 Assult Helicopter Co- (Vultures) South of Saigon, U Minh Forest, Delta, and all parts in between |
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Ayo Irpin, Ukraine!
Join Date: Mar 2004
Location: Santa Cruz, CA
Posts: 12,552
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Quote:
Are there multiple speeds involved with driving individual components off the pulleys? How are you going to keep that drive shaft lubed? How many hours are you going to get on that drive shaft before the lash wear is out of spec? What will be needed to R/R that drive shaft as opposed to R/R belts? Sometimes engineering is not driven entirely by complexity or the number of components used.
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Harmlessly passing gas in the grassland away; Only dimly aware of a certain smell in the air |
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Air Medal or two
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Right now the system is toast between 1oo and 200 hours
A simple ring gear arrangement will weigh no more, should out last all other components involved. I do appreciate everyone's help. If in a car loses are 10 to 15% through a simple drive train. these belts is a parasitical nightmare . Plus all the adjusting all the time
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Unregistered
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I have all that info in some books in my office, it'd prolly take an hour to find all the info to answer your questions given that there are a go-zillion variables.
Are you talking about a standard V belt? Which size, A,B,C,D, DD? Yeppers just like bras. Pitch diameter of each shieve, RPM of smallest, etc. Number of belts, seperated or banded? Or are you referring to a serpantine belt? Which belt manufacturer? I'm not aware of any general rule of thumb that applies to all V belts. Life ain't that simple in my world. Too damn many variables. BUT, I will say that a properly designed and installed belt system can reach 95% efficiency and should always be over 90% efficient or someone screwed up. |
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Navin Johnson
Join Date: Mar 2002
Location: Wantagh, NY
Posts: 8,808
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Quote:
Yes Quote:
Quote:
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Don't feed the trolls. Don't quote the trolls ![]() http://www.southshoreperformanceny.com '69 911 GT-5 '75 914 GT-3 and others |
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Unregistered
Join Date: Aug 2000
Location: a wretched hive of scum and villainy
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Quote:
Needs some serious engineerin'. |
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Air Medal or two
Join Date: Jul 2003
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Posts: 14,081
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Thanx
i could live with a couple belts.......but OMG! From engine to 1st jackshaft its a set of 4 thats right, engine shaft with 4 pulleys to jackshaft again 4 pulleys they are about 6 inches across on the jack. maybe 4" on the engine...i understand they were stepping torq up and RPM dwn........ I am thinking cause they are "V" belts...there is a loss right there...
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Un-Registered User
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A ring gear would be a solid coupling whereas the belts/pulleys have more compliance.
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You do not have permissi
Join Date: Aug 2001
Location: midwest
Posts: 39,923
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Best guess:
Large lightweight balanced pulleys(aluminum/mag) using the same overall ratio, thin flat ribbed belt, add tensioners where needed to make the path round but flexible under heavy load. |
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Max Sluiter
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Quote:
![]() But I guess he must be talking about shafts directly from the engine/transmission rather than with some layshafts.
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Un-Registered User
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Quote:
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