THE ENGINE:
I originally planned for a diesel of around 150 hp for the boat but after finding the heavy duty hydraulics an old truck with a recently rebuilt Cummins in it, I'm now up to 250hp. This engine is much heavier than I planned so I still have my eyes open. I hate that I had to pass on a Cummins L10 a couple moths back. Same hp with half the weight.
HYDRAULIC PROPULSION:
NEW CONFIGURATION
Now that I have fallen into a deal and acquired all my hydraulic pumps, motors and drive train to the wheels with spares (see the blog), I have redesigned the
drive train yet again.
The rough plan uses a separate pump which is vaiable speed both forward and reverse, for each wheel with a crossover valve allowing both wheels to drive from one pump should one fail.
Both pumps driven through belts, for slippage, feed the motors mounted on gearboxes attached directly to the wheel. No sprockets, no chains, no transmission. Simple... I hope.
ORIGINAL CONFIGURATION
PUMP:
| MFG |
Part Number |
RPM |
GPM |
Pressure |
Price |
|
Dowty
| 9-2069-P
|
1800 Cont
2100 Max |
48 Cont
56 Max |
2800 Max |
$289 |
|
MOTOR:
| MFG |
Part Number |
Duty |
Pressure |
GPM |
Mtr Torque |
RPM |
HP |
Reduction |
Torq@Wheel |
Cost Ea. |
| Bailey |
116-928
|
Cont
Max |
2000
2800 |
25
30 |
1310 ft/lb
1542 ft/lb |
130
150 |
32.4
44.0 |
3.5:1 |
5688 ft/lb
7708 ft/lb |
$229 x2 |
MOTOR CONTROL:
| MFG |
Part Number |
GPM |
Press |
Cost Ea. |
|
| Dowty |
9-7497-30 |
30 |
3000 |
$299.95 x2 |
|
ELECTRIC PROPULSION:
AC: A 3 Phase Electric Drive was under consideration, but a system of this type is way over budget. Given the steep price of the generator, the cost of a frequecy drive for each wheel nearly matched the cost of the generator.
DC: DC power (200+ volts) was under consideration longer than the AC especially after finding a source for several 30 - 50 hp motors and some 40 - 65 KW generators in the 200 - 250 volt range available. Newly developed IGBT's would make building a PWM drive simple.
PADDLE WHEELS:
Two paddlewheels:
| Diameter: | 12 feet |
Insert
Paddle
Drawing
|
| Width: | 4 feet |
| Spokes: | 14 |
| Buckets: | 18 inches |
| | |