Cat 633D question

[gkprice]

Hello all,

I have a question about 633D, 25W machines. The operators like to half-open the floor and use the resulting straight edge to blade roads, level the fill, etc. They swear up and down it's OK to do so.
The mechanics say this should never be done, it is hard on the rear of the machine and the linkages and cylinders that open and close the floor.
One of the shop guys says he saw a show on National Geographics TV about big earthmovers. He said they specifically mentioned this practice.
I have searched the operater's manuals and can find no mention of this practice-yea or nay. Can anyone cite Cat literature that addresses this issue?

Thanks,

Keith

 

[Gavin84w]

No need to site any Cat manuals mate, you just don,t do it, your mechanics are 100% on the money. The floor on the elevator is just that, a floor to hold the dirt in during loading and hauling, sure it will bulldoze to a degree during the dump cycle as it rotates backward and the machine travels forward but if your roads need grading get a grader and if you run a fleet of scoops with out a grader you will suffer production loss-simple really. What i think someone is confused with is the fact that with an open bowl scraper you can raise the apron and pull the ejector forward and use it to grade, this is quite common and you are using the cutting edge to do the work and it is designed to take those forces, a 633D floor is not.

 

[WabcoMan]

Don;t do it.
Your maintenance guys are right on the money.
633 bowls aren't designed for that kind of thing.

The only elevators that have a proper strike off blade are the Wabco's and any of the other manufacturers that used a Hancock type bowl (Michigan, MRS, Euclid/Terex etc)

Happy scrapin'

 

[Buckethead]

Can anyone cite Cat literature that addresses this issue?

I wouldn't feel right doing it, unless the owner of the machine wanted me to. I have a John Deere 862B manual that says it is acceptable to do it with a JD 862. I don't have a Cat manual handy unfortunately.

originally posted by Gavin84W:

if your roads need grading get a grader and if you run a fleet of scoops with out a grader you will suffer production loss-simple really.

I agree. Usually there is no grader available so the scraper operators do the best they can.

 

[Jck64]

It is hard on the floor, especially in hard material. I have seen several that the pins broke or even the cylinder itself gave way from dragging to floor too much. 33's dump like no other scraper, they take time to get a feel for. The greenies always leave a nice turd when they dump. Gets old beating across all day.

 

[Buckethead]

33's dump like no other scraper, they take time to get a feel for.

JCK I did not know that when I posted my answer above. I have run scrapers just not a 633. All the self-loading scrapers I ran had a regular ejector and the floor slid back to dump. How does a 633 dump?

 

[Jck64]

The D models have a set cutting edge with either teeth or a smooth edge. The floor isn't attached to the cutting edges. The floor pivots back as it is opened, there is a large hydralic cylinder that opens and closes the floor. The lever that opens the floor should kick off when the floor is opened up and vertical to ground. 33's are tricky, mainly because the floor will open up all the way leaving giant turds in the fill. E models are similar to 23's in that they have a regular ejector and sliding floor.