2.5. Cushion Blade

When we discussed about the application of bulldozers, I told you that the bulldozers are also used for supporting the other machines, so it helps in assisting the other machines in its job. Say this is the schematic sketch showing a scraper. So, this is the bulldozer, so your bulldozer is helping to push the scraper. This scraper is also when earthmoving equipment, we are going to discuss about this equipment in detail in the next lecture. This scraper has a bowl and a cutting edge. So, the scraper will cut the earth and fill the bowl that is called as a loading operation. So, during the loading operation, I have to supplement the power of the scraper with the help of a pusher, this pusher is nothing but your bulldozer.

A cushion blade is a specialized type of blade on a bulldozer that is primarily used to push other machinery, such as scrapers, rather than for traditional earthmoving tasks. The bulldozer acts as a pusher for the scraper, which does the digging and collects earth in its bowl. During this loading operation, the bulldozer provides additional force, which helps the scraper function more effectively. This is particularly important during loading operations when the scraper needs extra support to fill its bowl with earth efficiently.

Think of the cushion blade like a friend lending a hand during a tough task. Imagine a friend trying to push a heavy cart up a hill. While your friend is doing their best, you step in to give an extra push. The cart moves more smoothly and quickly up the hill because of your assistance. That’s how the cushion blade supports the scraper, enabling it to work better and move material more efficiently.

So, this bulldozer will supplement the loading power of the scraper thereby you can enhance the productivity of your scraper. So, only during the loading operation I need the help of the bulldozer. So, for those bulldozers, so I am not going to use the blade for earthmoving operation. So, I need a blade for just pushing the machines that blade is called as cushion blade, C blade. These blades are generally the height will be shorter. So, that the height of the blade, the blade will not disturb the rear wheel of the machine which it is pushing. So, the blade height is shorter and this blade no movement is possible, I cannot tilt or pitch or angle nothing is possible with this cushion blade it is just fixed. So, these cushion blades it is productivities also less.

Cushion blades have specific characteristics that distinguish them from other types of blades. They are lower in height to avoid interfering with the other machine's wheels while pushing, ensuring that the rear wheels of the equipment being assisted do not get obstructed. Also, cushion blades are fixed, meaning they cannot tilt or pitch like other blades, which further limits their versatility. Because their main function is to assist other machinery rather than perform traditional earthmoving tasks, their productivity in this role is generally lower.

Imagine using a tiny, fixed ramp to help your bicycle get over a curb. The ramp doesn’t move or adjust; it simply helps your bike go over the steep edge without getting stuck. This is similar to how a cushion blade works—it serves a specific function of helping other machines without versatility, making it efficient in its limited role.

With respect to earthmoving operation it is not commonly used for earthmoving operation, it is used primarily only for pushing the other machines. So, we have discussed about different types of blades so far. So, straight blade, U blade, angle blade and cushion blade and SU blade. Straight blade as I told you for harder terrain, you have to go for straight blade, because their cutting ratio and load ratio is high. But the problem with a straight blade is you will have end spillage, when you push the earth, there will be spillage of material at both ends of the blade that will reduce the productivity of the bulldozer. So, in that case I have to go for the U blade, if you wanted to reduce the end spillage, you are going to push the material for a longer distance and if the material is easier to handle it is preferable to go for U blade. Because U blade has a greater blade capacity also, bigger in dimension. So, similarly the cushion blade it is used only for pushing the other machines, when the bulldozer is used for assisting the other machines then it you can go for the cushion blade.

Overall, cushion blades are not used for traditional earthmoving; instead, they are specifically designed to push other machines during operations. While there are various types of blades suitable for different soil types—like straight blades for hard terrain and U blades for softer materials—cushion blades have a unique function. Their design and limitations mean they are best used in situations where the bulldozer is acting as a support mechanism, rather than engaging in direct earthmoving tasks. This highlights the specific nature of each blade type in terms of functionality and efficiency.

Think of cushion blades like a movie director's assistant. While the director (the bulldozer) is crucial for making the movie happen, the assistant isn’t there to act or direct but to help get things done smoothly behind the scenes. The assistant’s role is different but equally important when it comes to ensuring that everything works well together during production.

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