I have never operated a d9 size machine, so was wondering about them in production rates.old timers say two pushes with a d6 equal a d7 which does not add up to the production handbook rates. in the handbook all the smaller ones are bunched together d6 thru d8 then when you jump into the d9 it really jumps up it only weighs 20000 more then a d8, is there a weight thresh hold that is reached, or is a d9 just a Godzilla dozer. I can see the rates for d10 and d11 the machine operating weights really jump up.what am I missing here??
Somebody has had to of operated a d8r/t and a d9r/t.with a close to ten ton weight difference, does the d9 really out produce the d8 by that much????
I can only compare an 8n to a 9n and yes the 9n will rip more and push a healthy pile of dirt. I ran them in hard rock and needed the weight the 9 provided.
Yair . . . earthscratcher . I dunno, but I wouldn't question the rates as published by Cat. Undoubtedly they were established using the correct and established production techniques in (probably) ideal conditions . . . the results I imagine would be verifiable and repeatable. There is only one way to push dirt to reach maximum production and, in the real world, a good operator on a smaller tractor can easily out produce a wannabe on a larger rig . . . disregard all that folklore "two pushes on a six equals one push on a seven" nonsense Cheers.
The reason that D9 and above are put together production-wise is that the D9 is the smallest model that is classed as a mining dozer as opposed to the earthmoving/construction line which stops at D8. I've never compared the 2 models side by side on the same job but a later-model high drive D9 will push gangbusters compared to a D8 of similar vintage.
on short push rates the difference between a 7 and 8 is 275yds per hour with a 20,000 lb weight difference roughly! on short push rates the difference between a 8 and 9 is 700yds per hour with a 20,000lb weight difference roughly,that difference in yardage is what a d6 pushes roughly in a hour, which is almost half its weight! and I thought a d8 was a mountain mover, what a machine this d9 must be. WOW
I have owned a d8K and a d9h................... A world of difference between the two.
Size, I remember after spending lots of time on a D375, then getting on the D8, the 8 felt like a small dozer. D9 ? Yeah does more than a D8 but didn't feel too much bigger. Funky decel from the D8 though.
The cu. yds. for the blades should be easy to look up and the extra weight of the larger machine should push the bigger blade easier. I'd be curious if a Komatsu D575A Super dozer with a 90yd. blade is twice as productive as a D475 or D11 45yd. blade all things being equal.
A dozer with twice the hp of a smaller model, is never twice the size. The blade is not twice as wide, so you have more hp per foot of blade which is probably one of the biggest factors. They are also not twice as wide. Look at a D4E. 75hp something like 16" grouser plates, 8ft blade. A D10 84W from the same time period. 700hp, maybe an 24 foot blade and 24" wide plates (but a much longer track frame)
I currently own a D9T and a D8T and the D9 is around 50% more of just about anything you can think of. Both machines have their places. However,photo’s never do them justice.They are much bigger in the flesh. To move muck requires weight,horsepower and fuel consumption.