U/C is it better to be slow or fast???

[Deeretime]

I have been running iron since 5 and one thing that i could never completely understand was the corilation between speed and wear on U/C.
my dad and some of the old boys from the company always told me that walking a hoe in fast mode or running the 850c in 3rd was hard on u/c.

I always thought that if you were a good dozer op. you could cut grade @ 2.5-3 Atleast i can on ours. So i am traveling the same distance as i would at a slower spd and doing the same amount of work, so the only diference is that i am being more productive.

what are your opinions on this topic?

 

[rutwad]

Speed kills...:d

 

[Deeretime]

But how? same distance same wear as far as i'm concerned, that kind of speed produces no more heat than it would going slower would it ??

 

[nilzlofgren]

I have been running iron since 5 and one thing that i could never completely understand was the corilation between speed and wear on U/C.
my dad and some of the old boys from the company always told me that walking a hoe in fast mode or running the 850c in 3rd was hard on u/c.

I always thought that if you were a good dozer op. you could cut grade @ 2.5-3 Atleast i can on ours. So i am traveling the same distance as i would at a slower spd and doing the same amount of work, so the only diference is that i am being more productive.

what are your opinions on this topic?

Here is the answer.http://http://www.deere.com/en_US/cfd/construction/deere_const/media/pdf/DKB765.pdf

 

[Greg]

You don't produce enough heat in the undercarriage of a machine to do any damage. All of things in the Deere publication listed in the post above explains it very good. One of the better publications I have seen on the subject.

 

[JDOFMEMI]

Like Greg says, that is one of the best presentations I have seen to explain U/C wear and its causes. I especially like the graphic showing the wear in reverse.

I have understood this for many years, but never seen it explained in such an easy to understand way.

 

[John C.]

High speed operations cause impact loading on the sprockets and bushings, especially in reverse. I have seen up to 30% faster wear for dozers with operators who continually run third gear reverse. I usually advise customers that I like being paid to work on undercarriage, so keep up the good work.

Excavators use a different kind of track link and they don't move nearly as fast. I generally only ask operators to make sure the sprockets are always on the down hill side of travel. Reverse operation still wears out chain faster but excavators are only carrying their own weight.

 

[rutwad]

So don't back up, don't turn, don't work on hillsides, don't work along crowns are swales, don't go fast, don't go far and your undercarriage will last longer!!!

 

[2stickbill]

Makes you wonder why some old standard shift dozers had five forwards.

 

[Deeretime]

Wow alot of that stuff i knew already but that definately reinforces my dad's point.

I think i will print that off and go through some of that material on monday's start up meeting.

Thank you guys :drinkup

 

[lgammon]

mmm so if i don't use the machine it will last for ever!!!! wow i just saved thousands in fuel and maintenance

 

[coalrulz]

mmm so if i don't use the machine it will last for ever!!!! wow i just saved thousands in fuel and maintenance

All sarcasm aside, there are slight changes to operator procedures that can be made to prolong undercarriage life, after all undercarriage accounts for more than 50 percent of maintenance costs of a dozer over it's life.

 

[coalrulz]

Here is the answer.http://http://www.deere.com/en_US/cfd/construction/deere_const/media/pdf/DKB765.pdf

Interesting article. If you take the information about forward and reverse wear, and apply it to a high track. The high track "even in forward" is going over and idler "rear" with track chain loaded, where as a low track is not.

 

[JDOFMEMI]

Which is why parts of the U/C on high tracks lost some life from the beginning. It led Cat to develop better components to get the life back up to the acceptable range. The arguement is that they are more productive, so it balances out. Not always though.

Notice the smaller Cat machines all going back to low drive.

 

[rutwad]

Which is why parts of the U/C on high tracks lost some life from the beginning. It led Cat to develop better components to get the life back up to the acceptable range. The arguement is that they are more productive, so it balances out. Not always though.

Notice the smaller Cat machines all going back to low drive.

What makes them more productive??

 

[johncxr]

850J. I set the reverse speed to 130% and boy the bushings on the chain literally cracked and started flaking off within 300 hours.

 

[Dozerboy]

What makes them more productive??

It eliminates the final drive system that oval track dozers have. The drive sprockets don't have to carry the weight of the dozer only drive it so more pushing power. The tracks fallow the contours of the ground better so more traction and smother ride. I'm sure theres more too.

 

[deerefan]

So what's the verdict? Go slower and take more tome to do the job, but have your U/C last longer. Or go faster get the job done quicker, make more money, but more maintenance?? im confused.

 

[sultan]

So what's the verdict? Go slower and take more tome to do the job, but have your U/C last longer. Or go faster get the job done quicker, make more money, but more maintenance?? im confused.

From my very limited experience with dozers, you can be just as productive and sometimes even more productive doing big heavy slow pushes than by fast and light pushes, and reduce the wear on the undercarriage. I haven't run any hydro dozers, so I can't say what to do with them, but when pushing a full bladeful on a powershift push cat, first gear gives much better performance and efficiency than second. You also have more time to think and control grade better in first gear. In other words, you can get an area to the basic (but not finish) grade just as quickly and perhaps quicker by doing full pushes at a slow speed rather than by going fast and doing light pushes. You normally can't get full pushes going much faster than 1st gear speed. Thus, slow but full pushes are just as productive as fast light pushes, but slow pushes reduce the wear and tear on the undercarriage.

For smoothing and final grade though, 2nd gear seems better, because you just want to make fine adjustments to a large area quickly, and no great earthmoving pushing force is needed. 3rd gear is just for travel around the job site in a 3 speeder.

I'm no real dozer operator though, I've just messed around with them a bit, so don't take my words as the 'facts.' What do the real dozer operators here think about this?

 

[nilzlofgren]

3rd gear is just for travel around the job site in a 3 speeder.

You would make your undercarriage a lot happier if you never used 3rd gear, especially in reverse.