Flange bearing question??

[Frank S]

Hi Steve; Perhaps you did not read my post completely I mentioned (Full HP Side loading)
duel Opposing loads are consummate of inline loading.
most belt driven accessories are located above the center-line of the crank shaft loading of this nature is counteracted by the downward thrust of the pistons during the power stroke.
even at that during a tear down the front main bearing will show top wear where as the rest will show more wear on the bottom half of the mains. even so 15 to 20 hp being pulled from belts on the crank shaft of a 200 to 600 hp engine is like wearing a properly fitted back pack during a hike you feel its presents but can ignore it for long periods of time a whole lot longer than trying to carry a single 2 gallon can of gas in one hand.
Gear driven accessory drives are designed for both belt driven and inline loads.
hope this clears up any miss conception of what I have been saying.
I have built units that had such a high single side load that not even a factory made load adapter mounted to the bell housing could handle them an out board bearing had to be installed in order to prevent designation of the engine bell housing. even then if a solid happened to be sucked into a mud pump causing it to lock down when you have 5 sets of 4 teamed "V" belts having a cross section of 2 inches it is going to either shuck the 15 Inch diameter double helical pinion and 6 ft diameter bull gear, pretzel the connecting rod, or snap all 20 belts or rip the adapter and the out board bearing right off the back of the engine or explode the fluid head I have seen all of the above happen.
 

[tinkerer]

Thanks everyone for your replies, thoughts, etc. I have done some thinking and have decided to go with a short shaft supported by two pillow block bearings. The short shaft will be driven by a love-joy coupler off the flywheel. Instead of using my stub shaft, I plan on machining my coupler to fit inside the recess on the flywheel so that it will be centered. I will then build a round plate with a hole machined in the center that will slip over the coupler. I will then weld the coupler to the plate and bolt the plate with coupler to the flywheel. I decided to go this route over using my stub shaft for space reasons. I hope my description makes sense. One more ?. Will a 1" shaft supported by two pillow block bearings handle approximately 12hp running my gen head? Its a small two cylinder diesel running at 2800RPM.

Ben

[mobile_bob]

your 1" shaft will be just fine

before you go with the dual pillow block brgs, and seeing how you are going to make up the plate, bore and weld
in half of the lovejoy, you really ought to reconsider my option

you can limit the length to something much shorter than with dual pillow blocks

also their are flange mounted brgs that are self aligning, something that is going to be an issue with dual pillow blocks

if you are going to use  the dual pillow blocks, you will need  to have the mounting system very rigidly mounted to the engine
and very carefully aligned.

my vote would be to save the expense and the hassle

you can use tubing risers to bolt the outboard flange brg mount plate right into the engine block through the starter plate holes
they already exist and can be used as a pattern drill the outer plate.

basically it could all be done without the use of any machine tools, save for maybe the adpt plate that bolts to the flywheel and where you will
be welding in the lovejoy half.

the 1" shaft can also be bought already with a keyway running down the full length, not that you need it all the way, but it is always cheaper than having a shop key the end of a piece of shaft without it.

alignment would be very easy using stuff you probably already have in your toolbox.

the amount of side loading we are talking about does not warrant a dual pillow block setup, not unless you plan on using stamped steel elcheapo brgs, which i know you are not contemplating.  even a light series 4bolt flange brg will handle several hundred lbs of side load.

the other advantage to the flange mount is the ease of alignment compared to that of a pillow block brg, no shimming needed with the flange
brg and likely will have shimming to do with a pillow block brg mount and definitely with a dual pillow block mount.

fwiw
bob g

[EBI-WPO]

Thanks for posting that Bob. I think the original intent got skewed, and then overengineered. With a well centered & secured shaft fastened to the flywheel, spacers between the starter plate, and another plate large enough for a good quality flange bearing, you could easily mount a pulley outboard of the flange bearing. It would easily carry sideloading, with minimal effect on the engines bearing.

Hey that sounds a lot like what I'm doing... (on my Yanmar which will be driving a 5K Kato head)

I made a shaft from a heavy schedule flanged stub I had laying around. It appears to be a 2" ANSI flange with a 2" OD, which I turned down to 1-15/16" which I had a flange bearing for. I turned a shoulder on the face of the flange so it would pilot into the recess where the flywheel bolts are for centering. I then drilled a 6 bolt pattern in the flange/shaft, as well as a matching pattern in the flywheel. The shaft is a very snug push fit in the flange bearing. I have the appropriate size toothed pulley to match my generator, and a 1-15/16 taper bushing to mount it to the shaft. I see no issues with this performing/lasting a very long time.
KISS? Yes. Adequate? Yes.

Terry

[EBI-WPO]

More.

[tinkerer]

Bob, thanks for the reply on your idea. I went back and reread your post and I like the idea. Thats sort of how I originally wanted to do it but I hadn't thought of "piloting" the end of the shaft nearest the flywheel. The engine bearings will still be carrying some of the sideload right? When the flange bearing is new it probably wouldn't be much, but what about after it wears a little? I have contacted yanmar about sideloading and they don't recommend it at all. This is my only concern.

[tinkerer]

Terry thanks for the pictures! Looks like its turning out well. Did you get your yanmar from Surplus center? Is it the 2TNV70??

Ben

[EBI-WPO]

Tinkerer,
Yes it is also a 2TNV70. I am using the original 2" wide toothed belt from the Kato system. I will mount the pulley just outboard of my flange bearing, which will be mounted as close to the flywheel as possible. I plan on running my engine right around 2600 RPM, if I remember my calculations correctly. Should be adequate for 5K. My project is one among many that share too little time, but want to finish it before winter.

I don't believe a quality bearing would let you down for a long time.

Terry

[Frank S]

This is the bearing style everyone has been talking abot

[mobile_bob]

it would appear that even if you made the unit very close coupled the side loading would be half that of direct drive off the flywheel
and if you extended out to a reasonable length, perhaps as little as a quarter of the side loading would be transmitted to the crankshaft.

even that could be reduced further with proper pulley placement, wherein if you slid the pulley onto the shaft where it fit over the outboard
flange brg as far as possible, the side loading transferred to the crankshaft would be even lower, perhaps as little a 1/6 or less.

also bear in mind, proper belt drive engineering, with a bit larger pulleys than the minimum called for would allow for lower belt tension in the
first place.

i am running dual AA belts, with enough contact area on my unit that i run no more tension than it takes to keep the whip down, basically
very loose by most standards,there is no slip, no heating, no dusting and probably less than a quarter of the side load seen in typical applications engineered to use the smallest possible pulleys and the fewest belts.

sometimes just running dual belts or another groove or two allows you do do things that aren't normally done.

bob g

[mobile_bob]

fwiw

i would also like to add, Terry does nice work!



if one has a machine shop at his disposal, and is so inclined, he can do lots of cool stuff.

bob g

[EBI-WPO]

Bob,
I can't remember the exact belt cofiguration, but it is 2" wide with 1/4" teeth (I think), but quite limber construction. Kato used it between the motor & Generator on their systems. It requires little tension to efficiently transfer power, and last many years as long as aligned correctly.

Poor pic of genset below. Sorry, none of the belt drive, I'll have to take some soon.

Oh, and thanks for the compliment.

Terry

[mobile_bob]

when i mentioned notched belts i was not referring to cog belts, although they run at very low relative tensions and side loading
and while reportedly being noisy run practically forever.

i mentioned notched belts such as the AX or BX series which have notched undersides but don't engage teeth in the pulleys, the notched
belts are able to deliver about 30-40%more power for a give application compared to a standard V belt. this allows in many cases lower tensions and therefore less sideloading.

Terry, nice paint! 

sure would like to see the completed project

bob g

[EBI-WPO]

Bob,
The pic in the back of my truck is when I picked up the Kato Genset in Austin Tx. It is a 50 hz unit rated at 5K, but knowing Kato, and running it at 60Hz, I'm sure it would produce more if asked to. The motor is identical to the gen head, with controllable field windings for speed control, and is a 12 lead configuration. Sounds like a 3 phase 5K unit came with my Kato find. The pic is dated from 2007. I gather my parts far in advance sometimes. I bought it on E-bay and got it for the initial/only bid of $1.99, yes $1.99. Cost me almost $200 in gas to go get it, but who am I to complain. Also came with a good Basler KR4F regulator, along with many other useful tidbits.

The toothed drive belt is only about 1/8" thick between the teeth. They do make their own brand of "noise", but have very little drag, and require little tension to do so. The Pulleys are of course toothed to match. I need to look up the belt family, so others can check them out. I am using the pulley, and belt from the 50hz side and a smaller one I bought to make the 2600 RPM translate to 1800 at the gen head. I cheated and let Kato do the initial engineering on my belt drive, I think they knew what they were doing.

Terry

[hal]

Steve, do you have any pictures of the Kubota DG972?