Rotary mower for tractor: operating principle, price, popular models

This procedure, such as mowing vegetation, is familiar to all agricultural workers and land owners.

It is carried out to clear the area of ​​grass. The most famous and oldest way to do this is to use a hand scythe.

However, this method is somewhat outdated today, since it is labor-intensive and, in addition to having a scythe, requires certain work skills.

The use of electric, gasoline and battery-powered lawn mowers is much more popular. But it is advisable on plots of up to several tens of acres.

What to do if the plot is a hectare or more in size? In this case, a device such as a mounted mower, which is operated with the help of a tractor, comes to the rescue.

A tractor is the main agricultural machine that performs many different operations, and installing a rotary (disc) mower on such equipment allows you to use the tractor for:

• making hay or silage;
• clearing the area of ​​wild grass;
• mowing green areas;
• mowing grass on roadsides or banks of drainage ditches.

Design and principle of operation

The basis of a rotary mower is a thick steel disk (rotor) on which freely rotating blades are mounted.
When the mower is connected to the power take-off shaft (PTO) of the tractor, the disk rotates at a speed of 1.5–3 thousand rpm (depending on the gear ratio).

Under the influence of centrifugal force, the knives take a working position, and when they encounter grass, they cut or chop it.

If the knife encounters a solid obstacle, then it is not affected by the kinetic energy accumulated by the disk, but by the centrifugal force, so the impact force is small, and if it was not possible to cut down the obstacle, then it rotates around its axis and returns to its working position.

The optimal diameter of the disks is 30–50 cm, and the relationship between diameter and mass is nonlinear, so disks with a diameter of more than half a meter are too heavy . To increase the working width of such a mower, several discs are installed in a row; there are four and even eight-disc devices.

If even this working width is not sufficient, then install one mower in front and two in the rear, but this is only applicable for tractors of the second or higher traction class.

Since the direction/speed of rotation of the PTO and the cutting disc are not the same, a cardan drive and various gearboxes

Four and six rotor mowers that are mounted to a standard rear suspension system use a combination of belt and gear drives.

This configuration is most effective on machines whose mower is installed vertically in the transport position. Although the direction of rotation of the cutting discs changes by 90 degrees, this change is fully compensated by both types of gearboxes.

a ski or wheel is installed on the edge of the mower farthest from the tractor , from which the required mowing height is then set. The largest six-disc mowers are often equipped with a frame with two wheels, between which the cutting tool is located.

Safety precautions for operating a homemade rotary mower

You must remember that:

• it is necessary to control the permissible loads on the mass itself and the axles;
• in order to avoid any unforeseen situations, it is best to use a tractor that has a cabin ;
• Before starting this device, you first need to move the mechanism to the transport direction position;
• you must remember that under no circumstances should there be any unauthorized persons in the driver’s cab while working;
• Moreover, it is strictly forbidden to transport the device if it is not secured or turned on;
• remember that if the unit is in a peculiar transport position, then in no way can you turn on the take-off shaft, which is responsible for the tractor power;
• Before each start of operation of the device, you must check that all parts are tightened and installed;
• if you need to change the oil, lining, or simply clean the mower itself, it is imperative that you first stop the vehicle itself and actually disconnect the cardan shaft;
• until the parts of the rotary mower have completely stopped, under no circumstances should you approach it;
• when working with the mower, do not wear loose clothing, as purely by accident, folds of it can get on the device, which can actually cause an accident;
• In addition, it is prohibited for animals or strangers to be nearby while the device is operating.

DIY mower

Installation methods

All rotary mowers are installed in one or more of the following ways :

• front hitch;
• side hinge;
• rear hitch;
• fastening via a manipulator;
• transportation using a towbar.

The front linkage is used only for cutting grass in the fields, because such an installation greatly limits the maneuverability of the tractor.

Side and rear linkages are the most popular, because they not only provide the operator with good control over the cutting tool , but also allow the mower to be moved to the transport (vertical) position without compromising the forward visibility and maneuverability of the tractor.

The manipulator is placed at the back or side, not through a standard suspension system, but by attaching it directly to the body. This is due not only to the large mass of the equipment, but also to its dimensions - being installed at the front, the manipulator will greatly impair visibility from the tractor cab.

The connection of semi-trailer and trailed devices is made using various trailer hitches, some of which must not only drag the mower, but also change its position relative to the tractor, moving it sideways.

Regardless of the installation method, the energy for operating the mower’s cutting tool is obtained from the power take-off shaft, and the transfer from transport to working position is carried out by hydraulic cylinders operating from the tractor’s hydraulic system.

How to connect equipment to the T-25?

It is important to choose the right mower model for the T-25 agricultural machine and secure it before work. You need to attach the mower to a switched off machine standing on level ground.

First, the longitudinal rods are fixed, after setting the wheel track, using special chains. The hitch rises to the upper extreme position. This is done by adjusting the lever, which is located on the shaft spline. The rear hinges are mounted at a height of 60.1 cm from the ground.

In front of the canopy, you must drive up to the mower in reverse and move the handle distributor to the floating position. Next, the tractor axle is connected, which is located on the frame of the equipment.

The frame axles of the mower have two sides. The rod on different sides should have dimensions: 0.29 cm, 0.25 cm. After moving the mower, its axles are secured. The end outside the axle should protrude 0.28 cm. The axles are fixed with the canopy rods and secured with latches.

Advantages and disadvantages

To objectively evaluate the advantages and disadvantages of a rotary mower, it must be compared with its competitors, that is, with :

• segmental;
• flails;
• sabers.

Therefore, we have prepared a table in which we summarized all the advantages and disadvantages of rotary mowers compared to other types of devices:

Types of mowers

There are two types of mowers available for the T-25 model:

• With segmented knife system;
• With disc rotors on which movable knives are fixed.

Segmental models differ from rotary ones in their design features, the method of cutting vegetation, and even their size. To make it easier for the reader to choose the appropriate model, we will consider each in more detail.

Segment mower model

The segment mower for the T-25 model is used for harvesting dense vegetation and placing it in shafts. Due to the low price and simplicity of design, the segment model is used in small private farmsteads.

It is attached to the tractor three-pointly on the rear linkage. The working bodies consist of metal bars with “fingers”. One block moves under the influence of the cardan shaft, the second remains motionless. The grass is cut as if with scissors. The standard width of a bar with fingers 2 is 2.1 m. Productivity is enough to process up to 2.5 hectares/hour.

The most common segment mower for the T-25 is KPO-2.1.

Features of the KPO mower - 2.1

Segment mower KPO - 2.1

Mows cultivated and natural grass in a spread pattern. Suitable for working with tractors T-25, T-40, MTZ - 80, YuMZ - 6. The cutting bar beam is made of reinforced metal, so the mower is not afraid of small stones and hard branches. And thanks to its narrow shape, the cut grass mass does not accumulate on the fingers and the KPO is less likely to become clogged.

Mowers for various tractors

Since the mounting method for tractors of the same traction class is almost always the same, in exceptional cases it is possible to install the appropriate system , we will talk about devices designed for equipment of different traction classes using the example of specific tractor models.

As an example, we will use the most popular models in the Russian Federation and the post-Soviet space, both those left over from Soviet times and those developed after the collapse of the USSR.

T-16

The T-16 self-propelled platform differs from a full-fledged tractor only in the location of the engine (it is installed behind the driver), therefore it is suitable for installing rotary mowers.

The location and number of PTOs on the T-16 depends on the modification, so attachments can only be installed where the power take-off shaft is connected. The towing class of the self-propelled platform is 0.6, but the engine power depends on the modification and is 16 or 25 hp. With .

Here are the most popular mowers for the T-16:

1. Z 064/3.
2. Z 178/1 L

Z 064/3

For some reason, these double-disc or twin-rotor mowers are called drum mowers even though they don't have a drum.
The working width is 135 cm, and the minimum engine power is 20 hp. With. However, they can be used even with a T-16 equipped with a 16 liter engine. s., but for this you will have to reduce the speed .

The mower is equipped with a hydraulic drive that puts it into working or transport mode, so the operator can change the position of the cutting tool from the tractor cabin, but the mower will have to be locked in transport mode manually.

Z 178/1 Lisicki

This Polish mower is in many ways similar to the model described above and is also a double-disc mower, but it does not have a hydraulic cylinder for moving to a working or transport position .

Since there is no such cylinder even on the T-16 as standard, the installation of an appropriate trailer hitch will be required, since the self-propelled platform has a pump and a separate hydraulic system.

The advantage of this model is that after switching to the transport state, the driver does not have to get out of the cab to fix the cutting tool, because in this position it is fixed by a special spring of sufficient rigidity.

T 25

T 25 is a full-fledged light (small) tractor, which has been produced since the mid-sixties of the last century. It also belongs to the 0.6 towing class and is equipped with various engines ranging from 20 to 25 hp. pp., so the same mowers are suitable for it as for the T-16.

Most modifications of this tractor are equipped only with rear drive wheels , but there are devices whose front wheels are also drive. The PTO and standard hydraulic system allow you to install attachments, including mowers, from any side.

T 40

The T 40 is a medium-sized tractor of traction class 0.9, so all mowers mounted with tractors of traction class 0.6, as well as more powerful devices, are suitable for it. It also supports the installation of attachments from any side, and the standard separate-unit hydraulic system provides the operation of hydraulic cylinders that change the position of the cutting tool.

Here are the most popular mowers suitable for the T 40 and other tractors of the same traction class:

1. KOR-16.
2. KND-210.
3. KRN-2.1.

KOR-16

This ride-on mower is designed for cutting grass on slopes, including slopes and berms of various canals, as well as sloping shoulders.
It even copes with trees or shrubs up to two cm thick , and the working width is 160 cm.

The manipulator is attached directly to the body, so the most popular is side installation. All the hydraulic cylinders necessary for the operation of the manipulator are already installed on the mower, so it is enough to attach it to the tractor frame and connect it to the standard hydraulic system.

KND-210

This mounted four-disc mower is designed for cutting any kind of grass and laying it in a swath. The device is installed on a standard three-point rear suspension and connected to the tractor’s hydraulic system, thanks to which the operator can control the position of the cutting tool from the cab , switching it to working or transport mode.

The maximum speed when cutting grass is 15 km/h, thanks to which a tractor with a KND-210 installed on it can process almost 3 hectares of field in an hour.

KRN-2.1B

This mower is in many ways similar to the previous model and differs from it in the presence of a protective cover that reduces the spread of grass. It is also mounted on a standard three-point rear suspension and connected to the tractor's hydraulic system.

The maximum speed when mowing grass is the same 15 km/h, while switching the cutting tool to transport mode allows you to drive at a speed of 25 km/h even in urban conditions.

MTZ 80 and 82

This tractor is a legend of the USSR and is still in demand in farms and municipal enterprises .

It combines sufficient power and the highest maintainability, thanks to which tractors produced even in the seventies of the last century are even now in good technical condition.

Both modifications of the tractor (MTZ 80 does not have driving front wheels, but MTZ 82 has them) are suitable for installing one large mower or several small ones, so any of the mowers described above is suitable for them.

In addition, MTZ 80/82 can be used in conjunction with larger mowers , for example:

1. Strige 3200 (ZhTT-3.2).
2. Berkut 3200 (KRP-3200).
3. DM TREX 320.

Strige 3200 (ZhTT-3.2)

This eight-rotor mower with a working width of 3.2 m can only be used with tractors of traction class 1.4 or higher.
The special shape of the knives on the rotors improves the quality of the cut, which is especially important for regular mowing of meadows during the preparation of silage or haylage.

After all, a neat cut does not injure the stem and root system, so the grass does not slow down its growth, which means the time between mowings is reduced.

After mowing is completed, the cutting tool can be moved to the transport position (raised almost vertically), which will allow you to move even on public roads.

Berkut 3200 (KRP-3200)

This trailed mower is equipped with two wheels, which puts less strain on the tractor chassis and also follows the terrain better . In the transport position, it moves strictly behind the tractor; to move it into the working position, the hydraulic cylinder moves it to the left or right (depending on the configuration), due to which it moves parallel to the self-propelled equipment, but to the side of it.

This position eliminates the pressing of vegetation by tractor wheels, which means the quality of grass cutting and mowing speed are increased.

In addition, it is equipped with a conditioner , thanks to which the mown grass, being laid in windrows or collected in stacks, dries faster. There are modifications without a conditioner, they are noticeably cheaper (1,270 thousand rubles with a conditioner and 990 thousand rubles without it).

DM TREX 320

Another trailed mower with seven cutting discs and a working width of 320 cm. Like the previous model, the DM TREX 320 moves from transport to working position and back using a hydraulic cylinder mounted on it , which displaces the mower relative to the base tractor, due to which it moves parallel to it, but from the side.

A shaft with constant velocity joints ensures the transmission of torque from the PTO to the cutting discs with minimal energy losses.

Specifications and prices

all the main parameters of these devices in a single table:

Attachments for Chinese tractors

Regardless of the place of manufacture of the tractor, the principle of operation and aggregation with this or that equipment are the same, so there is no difference whether the equipment is Chinese or Russian.

If the Chinese self-propelled device meets the basic parameters, that is :

• the presence of a PTO and a separate hydraulic system;
• sufficient engine power;
• traction class,

then you can install a mower on it, designed for a tractor with the same parameters, but made in Russia.

Which mowers are better – Polish or Russian?

Polish and Russian devices operate on the same principle, so the difference concerns only the materials used and workmanship. Old Soviet technology does not have a high service life, because all the elements are already worn out and the metal is tired .

However, after a major overhaul, even such a mower is in no way inferior to a Polish one. New Russian mowers, if made with high quality, are also in no way inferior to Polish ones, therefore, with the same quality of attachments, everything depends on correct use and maintenance.

But Soviet and Russian models have a significant advantage - you don’t have to wait long for parts for repair.

Therefore, with proper operation and high-quality maintenance, there is no difference between Russian and Polish mowers, because they work on the same principle , and Russian-made bearings and hydraulic cylinders have always been at least as good as Polish ones.

If we compare the reliability of replacement knives, then not a single manufacturer makes them from tool steel, preferring the most inexpensive metal, because they are consumables and in case of a defect they can be sharpened or replaced.

Where is the best place to buy a mower and how much does it cost?

The price of mowers for T-25 tractors depends on the following factors:

• Model - rotary ones are more expensive than segment ones, but their performance is higher.
• Equipment - mowers with protective brushes are more expensive.
• Manufacturer - the price for Polish models is higher than for Russian ones.

For small farms there is no need to overpay; it is enough to buy a small segment KPO 2.1. If you need to make hay for 10-20 cows, then the rotary model is more suitable. The price of Chinese models is lower, but they quickly break down and are not always suitable for our climatic conditions.

Let's look at the table where the best price for mowers for T-25 is:

Lower prices for used equipment. But the warranty and service do not apply to it. Before purchasing, ask how many years the mower has been in use and in what conditions it was stored. You can buy equipment no older than 5 years in good condition. The price will be lower by 10 thousand rubles. If you don’t have enough money at all and you like to tinker with equipment, then you can try to assemble the equipment yourself. A homemade mower will last no worse if you assemble it according to a ready-made scheme. You can find the diagram in this article above. But it is worth considering that if there are no suitable materials for assembly, you will have to buy iron, a welding machine and much more. The price of components and materials will be 3-4 thousand rubles lower than the finished factory model. Whether it is worth spending your time and effort is up to you to decide.