In agriculture, the preparation of plant feed for livestock is of great importance. However, mowing grass by hand takes a lot of effort and time, and this is now only done on small and private farms. Currently, to facilitate this process and cultivate agricultural land, rotary mowers of the KRN series have been developed. These devices are designed for mowing perennial and annual grasses intended for making hay and feeding cattle.
Rotary mower KRN series
The mower is used for mowing wild and specially sown grasses, as well as for processing road slopes. For such work, a function for adjusting the angle up to 30˚ is provided. Rotary mowers of the KRN series, as a rule, are aggregated with MTZ tractors of 0.8-1.4 traction class.
Mower KRN-2.1
Mower KRN-2.1
The rotary mower KRN-2.1 is produced not by one, but by several manufacturers. For example, it is worth noting the Moscow region in Lyubertsy, which produces equipment from Belarusian spare parts; Smolensk enterprise "Smolenskspetstekh"; Kirov PKF "Rakita". However, equipment from Tver is more popular due to its reliability and durability. It is worth saying that at present the model of the mounted mower KRN-2.1 is not produced in its pure form. Usually, the letter “A” is added at the end of the name, indicating the base model, or “B”. The model with the letter “B” has a slightly modified design - pulleys of the same diameter are used, as a result of which the tractor PTO speed increases to 1000 rpm.
Purpose
The KRN 2.1 rotary mower easily mows small bushes, removes weeds, cuts large masses of tall grass, and cleans pasture lands. At the same time, minor surface slopes and complex terrain are not an obstacle to work. It is also effective to use this model of rotary mower in areas where the yield is more than 15 tons per hectare. The equipment is able to work in any climatic zones and is aggregated with power units of 0.9-1.4 traction class through the hitch system of the tractor used.
Device
The unit drive operates from the tractor power take-off shaft. For this, a cardan drive, a V-belt connection, an overrunning clutch (providing idle speed), as well as a gearbox and rotary gears are used. To connect to the tractor, a suspension and a welded frame are used, which is attached to the tractor hitch (its lower links).
The cutting mechanism with shoes rests on the soil. To copy its relief, it has the ability to rotate in the bracket supports. The four rotors are equipped with eight knives of two sizes (the middle rotors are longer).
If the cutting mechanism encounters an obstacle, a special fuse is triggered, forcing the mower to turn around. It consists of two rods and wedge clamps held by a spring.
The blades of the KRN-2.1 rotary mower not only carefully cut the stems, but also throw them to the side. The field divider, mounted on a bracket on the right side of the cutting mechanism, prevents the grass from flying away. A divider shield placed on the spring at an angle in the direction of travel forces it to change the direction of movement and then lie in an even layer. During the next pass, nothing will interfere with the tractor.
To transport the mower to the desired location, activate its transport traction by lifting the machine blade and securing it. This is done hydraulically, using a balancing mechanism (which also serves to regulate ground pressure and avoid uneven surfaces). It consists of a hydraulic cylinder, a hinged lever, a flexible rod, a freewheel and balancing springs.
You can change the pressure of the shoes on the ground using tension bolts. When avoiding obstacles, you should, operating from the cabin, move the cutting mechanism to a position called “near transport”. After turning on the hydraulic cylinder of the tractor hitch, you need to slightly raise the mower. And then its hydraulic cylinder comes into action, allowing you to rotate the cutting mechanism.
Mower diagram KRN-2.1
1 – traction fuse; 2 – stand; 3 – subframe; 4 – axle; 5 – main beam of the cutting apparatus; 6 – knife; 7 – rotor; 8 – field divider; 9 – fence; 10 – cutting device bracket; 11 – suspension; 12 – axis; 13 – hinge frame.
Mower KRN-2.1B
Mower KRN-2.1B
A modification of the rotary mower KRN-2.1B is designed for mowing high-yielding and laid-down grasses at high speeds with laying the cut plant mass in the swath. This model of equipment can be used on slopes up to 100, while the modification with the letter “D” is used on inclined surfaces up to 300, which allows you to mow grass on steep road slopes and dams. The KRN-2.1B rotary mower is equipped with a safety device that allows you to protect the cutting elements from damage when colliding with an obstacle. The working part of the mower consists of four rotors located on the frame and equipped with eight plate knives, hinged. Suspension springs allow you to fairly accurately copy the terrain of the area and ensure an even cut of vegetation across the entire working width. The KRN-2.1B mower is aggregated with MTZ-80/82, LTZ-55.
Advantages of the KRN-2.1B mower:
- the all-welded beam of the working unit increases the tightness;
- due to the fact that the rotor supports are removable, repairs can be carried out without disassembling the timber;
- the pallet protects the cutting unit from abrasion on the soil;
- possibility of mowing in areas with a surface slope of up to 35˚.
Where is it used?
The mounted mower has certain design features that ensure adaptation to the necessary conditions of use. It is operated only with the participation of large agricultural transport, which is used for the purpose of mowing wild or crop plants in large areas (plots, fields) overgrown with small bushes and grasses.
The design of the mower allows you to adjust its tilt angle. Thanks to this feature, it can be used to remove heavy vegetation along road edges and near dams.
Working with a mounted rotary mower
Before you start working with a rotary mower, you should first check the track. If the dimensions are smaller or larger than 1.4-1.5 m, then it is necessary to adjust to normal. Afterwards, you need to adjust the length of the central tractor link.
Set the hydraulic system distributor to the “floating” position, then secure the rods with the axles of the attachment, and the cardan drive with the tractor PTO. Using a bracket, attach the casing chain to the central tractor link, maintaining a slight slack. It is necessary to install locking devices included in the equipment set on the longitudinal rods. Connect the hydraulic systems of both units, then lift the mower and adjust the axis of the hitch frame.
Before you start mowing, you should run the equipment in idle mode for a couple of hours. After that, check the condition of the bearings, nuts and belts, and only then start working.
On smooth terrain, you can maintain a speed of about 15 km/h, and on uneven terrain – a little lower. The mower must operate at its maximum cutting width and therefore the tractor should be driven so that the inner shoe is as close as possible to the edge of the cut vegetation. If an obstacle is detected using hydraulics, the working unit must be lifted, and during transportation it must also be secured using a transport rod and a stopper.
When moving the rotary mower over significant distances, it is brought into a vertical position, for which it is necessary to use the hydraulic system of the tractor and secure it using a transport rod and a locking device pin.
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:
- Z 064/3.
- 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:
- KOR-16.
- KND-210.
- 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:
- Strige 3200 (ZhTT-3.2).
- Berkut 3200 (KRP-3200).
- 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.
Criterias of choice
When choosing a mounted rotary mower, you should decide what crops are going to be mowed, what tractors they will be installed on and what the terrain and size of the areas being processed are.
If you plan to mow thick-stemmed hard crops, then the power of the equipment should be greater than that of mowers used for cutting soft grasses.
A variety of rotary mower models can be suitable for tractors, but it is best to use equipment from the same manufacturer as the power unit, or recommended for use with it.
The choice of mower is also greatly influenced by the availability of spare parts for the equipment and, of course, its price.
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:
| Mower type | Advantages compared to this type of mower | Disadvantages compared to this type of mower |
| Segmental | Easy to maintain, not afraid of stones and other solid obstacles | Low productivity, less accurate cut |
| Flails | Noticeably cheaper, suitable for cutting not only lawns, but also wild grass | Low productivity, less accurate cut |
| Saber | Slower to blunt, not afraid of stones and other solid obstacles | Not suitable for cutting thick grass and weeds |
Average cost of equipment in Russia (RUB)
| City | Provider | KRN-2.1 | KRN-2.1B |
| Nizhny Novgorod | LLC "Promtekhstroy", t. +7831212-96-69 | 145 000 | |
| Kazan | KaravanAgroTrade, t.+7 +7 | Check availability and price | |
| Moscow | TractorSpetsMash, t.+7 +7 | 129 000 | |
| Ufa | LLC "AGROSOYUZ", t.+7, | 125 000 | |
| Yaroslavl | LLC PKF "Selkhozmash", t.8-800-234-56-01 | 145 000 | |
| Novosibirsk | "ERIZ", t.+7 +7 | 135 000 | |
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.
How to choose a mounted mower
To select an effective unit for operation in specific conditions, you need to pay attention to the following factors:
- Composition of grass stand . The stiffer and thicker the plant stems in the area, the more powerful the model should be. Consider the likelihood of small shrubs, as well as changes in grass over the seasons. The stems of some plants are soft in the spring and become very stiff and hard in the summer.
- Area and topography of the site . For large fields with difficult terrain, it is better to choose implements with increased weight and coverage width. They will help you get the job done faster and at the same time level out small bumps. For mowing near the house, in the garden, you can choose lightweight attachments from the catalog that can be carried manually.
- Purpose of mowing grass . If you plan to harvest forage hay, you will need a tool that puts the hay into rollers. For primary mowing, models with mulching are chosen. They grind the cut grass.
- Type of equipment . For mounted implements, manufacturers indicate recommended brands of mini tractors and walk-behind tractors.
- Allocated budget . High-quality equipment cannot be cheap. Reliable equipment from well-known manufacturers is more expensive than its Chinese counterparts, but lasts much longer.
Operating principle and purpose
Rotary lawn mowers are equipped with a motor with a shaft that rotates the blades parallel to the soil at high speed.
Standard models of devices have double blades, but there are also examples with four-bladed cutters. The second type provides a cleaner cut.
The blades create a flow of air that sucks up mown grass fragments, which, due to the rotation of the mechanism, are poured into a special grass collector or onto the lawn at the side or behind the unit.
Many models are also equipped with a mulching function, which allows you to chop up grass clippings and fertilize the lawn with the resulting substrate.
Due to their power, rotary-type devices are used for cutting tough grass and processing heavily overgrown areas, as well as slopes and areas with uneven surfaces.
Types and classification
There are several types of rotary mowers. Depending on the mowing method, they are divided into:
- mulching;
- cutting grass;
- folding grass.
According to the type of attachment to the tractor there are:
- trailed;
- mounted
Tools are also classified according to the location of the knives relative to the tractor:
- side;
- front;
- behind.
The tractor mounted structure does not have its own chassis. It may have 1 support wheel or several. A mounted belt-type rotary mower is a device of low weight and performance. The tool works well on uneven surfaces.
The trailed unit consists of a frame that rests on pneumatic wheels. Cutting elements and control levers are mounted to the frame. A trailed rotary mower has a larger grip and is more productive. Such units are used in large fields.
What is a rotary mower used for?
The equipment is a structure made of disks mounted on a metal frame; steel knives are mounted on these disks on hinges (their number can vary, from 2 to 8). As the discs rotate, the blades spin and cut the grass. Due to the simplicity of the design, you can easily repair the mower yourself.
The rotary mower is widely used in agricultural complexes and on private farms. The equipment has become useful in public utilities and forestry. Work performed using a rotary mower:
- harvesting hay for feed;
- harvesting;
- mowing the grass before cultivating the land or planting;
- lawn mowing;
- cleaning grass along highways.
Using a haymower on the field
FAQ
Is it possible to use gasoline rotary devices for mowing grass on a slope?
Petrol mowers with a four-stroke engine are not suitable for slopes with an angle greater than 25-30°, since oil in this position can spill onto the cylinders and damage the machine. But under these conditions, units with two-stroke engines work effectively.
What power rating is optimal for lawn mowers?
For processing areas up to 400 square meters. m. A gas-powered tool with a power limit of 3 liters is enough. s., electric mowers up to 1000 W, for an area of up to 1200 sq. m. cars up to 5 liters will be required. With. and 2000 W respectively. Territories over 2000 sq. m are mowed with gasoline devices from 5 liters. With.
How long can grass be cut with a rotary cutter?
Many models are designed for shoots measuring 20-30 mm; more powerful units capture plants 60-80 mm tall. It is better to choose units with mechanical adjustment of the bevel level through the central lever; they are much more convenient to use.
Which direction is best to cut the grass?
It is preferable to cut the grass overlapping. In this case, it will be easier to drive the lawn mower forward and it will be possible to cover areas missed in the previous pass.
How often should a haircut be done?
Pushing a rotary unit through tall grass is much more difficult than cutting small growth, so mowing should be done at least once a week.
The variety of models of rotary lawn mowers allows you to choose the optimal device for a specific area in accordance with its size, complexity of the landscape and frequency of mowing.
