So, now let us discuss about the types of the scraper. So, there are different types of scrapers. So, in this we have classified based on whether the scraper needs assistance from the other machines during its loading operation or not based upon that we have done this classification. Pusher loaded means that scraper needs the assistance of a pusher or a tractor or a bulldozer during its loading operation, those scrapers are called as pusher loaded scrapers. So, there are certain scrapers which are self loading in nature. That means it does not need the assistance of other machines during its loading operation. That is why they are called as self loading. So, we can classify the pusher loader into single power axle and tandem power axle, we are going to discuss that in the upcoming slides. Similarly, self loading also there are different types, push-pull and elevating.

So, now first let us see what are pusher loaded scrapers? So, I have shown the schematic sketch earlier, this is your scraper machine which is leading. The trailing one is your bulldozer. So, hope you remember what type of blade you will fix for assisting other machines. So, you are using a cushion blade, C blade, C blade is attached to the bulldozer just for pushing or assisting the other machines. So, you know that the scrapers are tyre mounted, normally wheel mounted machines. So, for the wheel mounted machines, the tractive effort generated will be lesser when compared to the crawler or track mounted machines. So, the coefficient of traction will be poor. So, the amount of tractive effort generated will be less for the wheel mounted machines, to supplement the loading power of this wheel mounted scraper you can take the help of a crawler mounted or track mounted bulldozer.

So, now let us see what are these are single versus tandem powered axle scrapers? So, axle basically how do you classify the axle into powered axle and dead axle? See in our common vehicle say for example car, so you know that it may not be the case like all the axles are powered. So, maybe we only one axle may be powered the other axle we just dead ok powered in the sense the powered axle will transfer the power to the wheel those wheels are called driving wheels. So, the other axle will be just dead axle which would not transfer the power to the wheel, it will just act like a steering component. So, the axle which serves to transmit the power to the wheel is called a powered axle, the axle that carries a wheel without power to drive it, it is called as it dead axle, they are just acting like a suspension steering component.

So, next is your self-loading scraper. So far, we have discussed about the pusher loaded scraper where it needs the assistance of a pusher during its loading operation. In the scrapers it is self loading, that means it can load on its own, it does not need the assistance of another machine during its loading operation. So, but basically these machines are heavier and costlier when compared to a conventional pusher loaded scrapers that is one limitation of this machine. So, under the self loading, there are different types.

The another type of to self loading scrapers is your push pull scrapers. Here, these machines are not going to take the help of other machine like a pusher. But let us say for example, the scrapers which are employed in a project site. So, they will do a teamwork. Teamwork in the sense if there are 2 scrapers, one is in the leading position, the other one is in the trailing position. See, the one which is in the leading position. So, it will pull the trailing for the scraper when the trailing scraper is doing the loading operation.