How Does a Rotary Combine Harvester Work?

Whether you’re facing faulty equipment or expanding operational needs, choosing the right addition to your farm equipment lineup can be a frustrating process. With different types of machines to choose from, how do you know which will be the most beneficial to you? You also have to decide where to buy your equipment. If you’re still unsure, Machinery Pete’s expansive inventory has options for every budget!

If you’ve been searching for used combines for sale, you’ve likely come across both rotary and conventional harvesters. You might also be wondering, “What is a rotary combine harvester and how does it work?” In this blog, we’ll cover what makes a rotary combine different than a conventional combine harvester. We’ll also compare them head-to-head so you can see which is better for your farm.

What Are the 3 Main Functions of a Combine Harvester?

The primary function of a combine harvester is to make harvesting more efficient by performing several operations with just one machine. Here’s what you can expect to get done with the typical combine harvester:

Reaping: At harvest time, crops need to be cut from their stalks. The speed of cutting all depends on the machine’s header. What does the header do on a combine harvester? The header gathers your crops using an orienting reel to create batches and guide them to the cutting bar. The cutting bar then reaps your crop, and the augur transports the cut crops to the main part of the combine.
Threshing: The threshing process separates the edible part of the plant from the inedible. The main part of the combine contains the threshing drum, which beats the reaped crops. Straw walkers send the stalks out of the back of the combine while the edible grains fall into the collecting tank.
Winnowing: Threshing removes the stalks from your harvest, but lighter chaff can still cling to your grain. Combine harvesters also include a winnowing fan that blows away the chaff while the heavier grains are transported up with another augur into a collection tank.

Combine harvesters complete these three essential steps with one process, saving countless hours and dollars that would go toward labor costs.

What Is a Rotary Combine Harvester?

Rotary combines are a type of combine harvester that have innovated in the grain separation process. Instead of containing a threshing drum that slams your crops against rasp bars, rotary combines use a rotating helical drum to separate out the edible grain. This allows for the handling of more delicate crops and a threshing process that removes a higher percentage of inedible material.

Prospective customers might ask, “Do rotary combines have straw walkers?” Like most combine harvesters, rotary combines have a straw walker to carry the chaff and stalks from the thresher to the back of the machine. One of the most significant downsides to rotary combines, however, is the quality of straw they produce. Due to the nature of the rotating helical drum, the leftover straw is often twisted and broken.

Outside of the threshing process, rotary combines share most features with other types of combine harvesters.

Rotary Combine vs Conventional Combine

The key differences between how rotary and conventional combines work are in the speed and thoroughness of the threshing process.

Speed: Using centrifugal force, rotary combines can move plant material through the threshing drum faster than conventional combines.
Thoroughness: Conventional combine harvesters process your crops once before sending them on. Rotary combines keep your crops in the threshing area for two or three rotations, so they can remove even more of the stalks before starting the winnowing process.

Are Rotary Combines Better than Conventional Harvesters?

In most cases, rotary combines are easier to use and yield better results than conventional harvesters. This makes sense, as the rotary combine was an innovation made to the conventional combine in 1975, and it has only grown more advanced since.

On top of the operational advantages mentioned earlier, here’s why you might consider a rotary combine over a traditional machine:

Reliability: Rotary combines are produced with simplicity as a goal. They contain fewer moving parts than combine harvesters, and the less moving parts there are, the less that can break. Not only will you be up and running longer, but repairs will also be easier on a rotary machine.
Capacity: Having fewer parts also means that the parts with key functions, like the thresher and collection tank, can occupy much more space. In fact, to achieve the same capacity as a rotary combine, a conventional combine would have to be as big as a house!
Versatility: Rotary combines are more capable of handling delicate crops—like barley and peas—than conventional harvesters. That means you preserve more of your harvest.

Whether you’re expanding your lineup of machinery or considering upgrading from your current harvester, a rotary combine can save you time, money, and headaches.

Machinery Pete: Your Trusted Farm Equipment Provider

Wondering where to find the most reliable rotary combines without breaking the bank? Head to Machinery Pete! We carry major brands like John Deere and International Harvester, so you can always find the machine you’re looking for. We have solutions for every budget, and we also provide a platform for selling your farm equipment, so you can upgrade your lineup easier than ever.

Browse our inventory of rotary combines and contact us with any questions about buying or selling farm equipment.