View previous topic :: View next topic |
Author |
Message |
pete_k
Joined: 21 Feb 2013 Posts: 12
|
Posted: Wed Mar 27, 2013 4:50 pm Post subject: AT pumps questions |
|
|
Hello,
In a nutshell. Can someone explain the differences between the AT309, AT312 and AT203. In simple terms to as of yet a non-boat owner.
I understand the Hamilton 212 is a volume pump. Although coveted in some circles they need lots of HP and are usually meant for bigger boats or work boats. The AT's are pressure pumps (smaller nozzle, more response a bit faster and more fun). But why the 3 choices?
Also....Reverse. It seems to me the Split duct would be a better option than the HTR. Yet some opinions suggest the HTR is the better for reverse.
So. Is a 309 with a SDR just as good as a 312 with a SDR or 203? And what are the fundimental differences?
Thanks
|
|
Back to top |
|
|
ALEX
Joined: 02 Aug 2005 Posts: 176 Location: red deer
|
Posted: Wed Mar 27, 2013 8:40 pm Post subject: |
|
|
The 309 is an updated version of the Berkeley 12 JG mixed flow pump
Quiet,simple and reasonably priced
The 312 is a larger version for heavier boats,,,again with a mixed flow impeller
The 203 uses the same intake as the 312 but has an axial flow (open blade like Hamilton and Sport Jet)
For those boaters who prefer an axial pump
American Turbine now makes a large pump to compete with the 212 as well...the 231
|
|
Back to top |
|
|
pete_k
Joined: 21 Feb 2013 Posts: 12
|
Posted: Sat Mar 30, 2013 12:30 pm Post subject: |
|
|
Thanks Alex,
Whats the difference between mixed flow and axial flow?
|
|
Back to top |
|
|
ALEX
Joined: 02 Aug 2005 Posts: 176 Location: red deer
|
Posted: Sun Mar 31, 2013 10:33 pm Post subject: |
|
|
An axial flow is basically a propeller in a wear ring...low pressure...high volume
A mixed flow is partly axial and partly centrifugal...if you look at a Berkeley style impeller you will see the front edges of the blades bite into the water and then it is slung off the trailing edges at an angle;this gives it high velocity which is why virtually all high speed and river race boats use this pump;it does not grip the water as well as the axial flow and is not used in sprint boats
The 212 and Sport jet use a modified axial design with a tapered cone hub that is a partial mixed flow design.
|
|
Back to top |
|
|
ALEX
Joined: 02 Aug 2005 Posts: 176 Location: red deer
|
Posted: Wed Apr 03, 2013 6:47 am Post subject: |
|
|
sj impellers top row
hamilton 773 on left;atj/berk on right
Description: |
|
Filesize: |
235.3 KB |
Viewed: |
11179 Time(s) |
|
Description: |
|
Filesize: |
224.99 KB |
Viewed: |
11179 Time(s) |
|
|
|
Back to top |
|
|
|