Subject: Turbo compound belt drive
From: rotaryeng
Date: 6/3/2013, 3:07 PM
To: AAA-rotaryeng



BTW do you or anybody else on here know anything about the HP
capability of J section belts at 6000 RPM?

Paul Lamar


Paul, It depends on the number of ribs of course, but Gates has
charts for them. Go ti the Gates web site and search Micro-V. J
section is fairly small. K might be better for power transmission.
Bill Jepson

I did but I found no engineering manual. They wanted me to contact
them and they wanted a bunch of info. If you have a pdf please email
it.

The only thing I could download was this chart. I want to operate in
the red box so I know I need a J section. What about pulley diameters
for that range?

Paul Lamar


Paul, In j section all the pulleys you might normally use would be
fine. I believe the minimum radius suggested is about 2 inches. I
would stay up around 4 inches for power transmission. Bill

How many do you think I need to trans mitt 50 HP? Would a cog belt
be better? Some of those blower drives are well over 50 HP.

Paul Lamar

Yes Paul, for 50 hp. You would do well to consider a tooth belt
drive. A
multi-rib design would get really wide to handle that much power. A j
section belt would be at least 3-4 inches wide. One of the carbon fiber
backed[cog] belts in 20 mm would likely work. I checked the gates site and the 5
inch diameter pulleys with 20 mm width would handle the power. The biggest
trouble is speed. They suggest a max belt speed of 6500 fpm. A 5" pulley at
6000 rpm is 7800 fpm. What rpm do you expect at the output?
Bill

I'll be surprised if we get over 6500 RPM with Tracy's old
2.17:1 gear box and a wood Warnecki prop. My guess is we will have
close to 400 HP over all. Acid test for the old four pinion gear box:)

I'll put a new rubber coupling in it. No use in destroying a perfectly
good flex plate :) I was going to change the gear box in the RV4
to a 2.85:1 anyway.


Maybe two 20 mm wide on a 4.5  inch cog pulley.

Paul Lamar

The Rotary Engine News Letter. Powered by Linux. ACRE NL web site.
http://www.rotaryeng.net You Tube http://tinyurl.com/beqqxas
Copyright 1998-2013 All world wide rights reserved.