Virtual model of the excavator. Excavators advise excavators

Wheel excavators modern models can be equipped different systems management, but the requirements for them are the same, namely, management should be convenient and easy.

The driver must operate the excavator without much effort, since in just one hour of work he sometimes has to make up to 4000 inclusions of working mechanisms. Accordingly, this number increases several times over the shift.

Wheel excavator control system requirements

From any equipment used on construction sites, production or in a quarry, high labor productivity is required. The same requirements apply to the work of an excavator. The wheeled excavator is controlled by the driver, whose speed of action determines the productivity of the work.

Therefore, from the control system of excavators, which are produced by various enterprises and firms, the consumer expects certain qualities:

1. The effort required to press the levers and pedals should not be large.

2. The inclusion of mechanisms should occur smoothly.

3. The transfer of energy from control to mechanisms must be instantaneous.

4. Regulation is required simple but reliable.

5. Ability to work without failures at temperatures from -50O to +50O.

6. Using the maximum of automation.

Each control system taken separately can only partially fulfill all these requirements.

How to drive a wheeled tractor

Ways to transfer energy to the mechanisms of the excavator:

• Lever. Mechanical servo mechanisms may be used. The simplicity of design and the possibility of smooth switching with high sensitivity are the advantages of this method. Operation is complicated due to the presence a large number levers, rods and hinges. Management requires a lot of physical strength from the driver.
• Pneumatic. Gas (air) pressure is used. Smooth start, the ability to work with the engine off, simple blocking of individual mechanisms - all these qualities are among the advantages of this method.
• Hydraulic. The mechanical force of the liquid (oil) is used. Advantages: compactness and lack of levers with a complex design, requires little effort to operate. Disadvantages: dynamic loads on mechanisms due to sudden switching on.
• Combined. A combination of several methods in one system.

The complete set of a certain control system depends on the power of the excavator, the type of drive, the required reliability of actions. Large capacity bucket requires a lot of effort on the control lever, so manual mechanical control won't fit. It is used in wheeled excavators with a bucket up to 0.4 mg with a single-motor drive.

Operation of the hydraulic control system

This system has been extensively improved in last years, has found the widest application to the design of excavators, the mechanisms of which are driven by a single engine.

The design of the control system based on hydraulics has the main instruments and components:

• Pump. Works for high pressure. Provides in hydraulic system fluid movement. Powered by an excavator engine.
• An accumulator with a filter that plays a role in starting the engine of a temporary pressure tank.
• Distribution and return manifolds, control spools.
• Hydraulic cylinders that are on the mechanisms. Designed to turn mechanisms on and off.

Pipeline and fittings

Sometimes in design hydraulic control pump not included. In this case, the force on the lever is slightly reduced, but the system itself has smaller parts and assemblies due to fluid pressure and does not have a complex system of levers.

The hydraulic system without the use of a pump is used on low-power excavators and separately for brake system other models.

Control systems with a pump and hydraulics completely facilitate the work of an excavator who only moves the spools. The force is created by a pump, the liquid under pressure enters the cylinder mounted on the mechanism.

Operation of the pneumatic control system

It is used on excavators with different bucket sizes. The system uses normal air. The pressure does not exceed 10 kg/cm2, so the cylinders used are large and heavy, which is a disadvantage. pneumatic system management.

The main devices and components of the pneumatic system design:

• Compressor forcing air into the system.
• Oil and water separator.
• Receiver.
• Pressure regulator.

Coming from the compressor compressed air into the oil sump, then through check valve through the pipeline enters the tanks. On the way to the working cylinders, the compressed air is freed from moisture in the condensate collector, and is regulated in the electro-pneumatic distributor.

The spools can be controlled manually or electromagnetically.

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Excavators

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Fundamentals of high performance excavators

The successful use of excavators depends not only on the type and complexity of the earthwork in the construction of which they are used, its capacity and type of working equipment, but to a large extent also on the type and properties of the soil that the excavator must develop.

Excavators are designed for earthworks in soils of 1-1U groups. They may also develop other soil groups, such as pre-loosened, rocky and frozen soils (XIII groups).

Soil groups characterize the difficulty of their development. Group I is the easiest soil for digging, C group - soils that are more difficult to dig, III - even more difficult, etc. The difficulty of developing the soil depends on its properties, density, expressed in tons per cubic meter of soil volume. The more difficult the soil to develop, the lower the performance of the excavator.

Each driver, starting work, must know the type of soil; which he will have to develop in order to imagine what kind of excavator performance can be expected in such conditions.

When looking at the table, it is clear that the same soil can belong to different groups if its state has changed (for example, it was loose, but became hardened).

What kind of earthwork needs to be erected in these soil conditions is known to the engineer from the project and technological maps production of works. They show the dimensions of earthworks, the arrangement of vehicles, the ways of movement of the excavator and vehicles. Based on these documents, each driver is given a specific task with an indication of the deadline for its implementation. And here it is important for him to apply such methods and techniques of work in which the performance of the excavator will be the highest.

Before proceeding to consider the advanced organization of the work of excavators with various working equipment, it is necessary to briefly get acquainted with the types of earthworks in the construction of which excavators are used.

The size and shape of earthworks (Fig. 37) dictate the use of certain types of excavators with certain working equipment.

Thus, large channels (Fig. 37, a) are constructed mainly using dragline equipment. Irrigation canals, small in width and depth, are built by bucket-wheel excavators. The layout of slopes near canals (Fig. 37, i), embankments (Fig. 37.6) and dams (Fig. 37, c) is carried out by excavators with telescopic equipment or a dragline.

In the construction of large pits (Fig. 37,?), excavators with dragline equipment and a straight shovel are used, and in the construction of small pits, backhoes are used. The construction of large semi-dredging (Fig. 37, d) (semi-dredging - one-sided recess on the slope) is carried out by excavators with straight shovel equipment, and full recesses - also using a dragline. Small excavations, for example, in the roadway, are developed by excavators with backhoe equipment. Trenches (Fig. 37, e) are successfully constructed by bucket-wheel excavators.

In addition to the construction of these earthworks, a large amount of work is carried out by excavators for the development of soils in quarries (Fig. 37, lg) with loading into dump trucks and others. vehicles. This is explained by the fact that in such earthworks as embankments, dams, etc., it is often necessary to lay soils specially selected in quarries, and not those that are in the immediate vicinity of the structure.

Rice. 37. Earthworks, in the construction of which tori are used:
a - channel; b - embankment; c - dam; g - pit; d - semi-dredging: e - trench; w - quarry

The excavator digs all the earthworks listed above gradually, moving as part of the structure is ready to a new location within the design dimensions. At the same time, each time he covers such a work area, which is achievable for his working equipment. The working area of ​​the excavator is called the face. The slaughter is understood as the location of the excavator, the place of digging the soil and the location of the vehicle or unloading the soil into the dump when the vehicle is not in use.

The dimensions of the face are chosen so that the excavator can work with the highest productivity, i.e. with minimal time spent on filling the bucket with soil, turning to the place of unloading the soil, unloading the soil and returning the bucket to its original position for digging.

To ensure high performance of the excavator, the driver must fulfill the following general conditions for all types of excavators:
1. Choose the shape and width of the faces such that the angle of rotation of the excavator to the place of unloading the soil would not exceed 70 ° - At the same time, take into account that the smaller the angle of rotation of the bucket, the less time it will take to turn.
Since this angle depends on the position of the vehicle, it is necessary to provide for the most favorable ways for the operation of the excavator to access the vehicle and the sequence of its loading.
2. The height or depth of the bottoms must be chosen in such a way that the bucket is filled “heaped” in one movement of the bucket. The size of the "cap" over the bucket, as you know, depends on the angle of repose of the soil (for dry sand 25-35°, for dry clay - 40-45°); due to the “cap”, the volume of soil in the bucket increases by 20-25%.
3. Choose the length of the face so that the number of movements of the excavator is minimal, since maneuvering and relocating the machine causes a loss in its productivity.
4. Carefully prepare the bottom of the face along which the excavator moves, smoothing out excessive irregularities, removing stones and boulders, providing the bottom with a slope to prevent the accumulation of groundwater and surface water.

The driver should not try to load large stones, boulders, rock fragments into the bucket, spending useful time work. They are either bypassed or pushed aside with a bucket.

Poor ground conditions in the face can complicate the movement of vehicles, create pauses in its loading, and thereby reduce the productivity of the excavator when working in the face.

5. Strive to reduce the time of work operations. If, for example, for single-bucket full-revolving excavators, the time of a full work cycle (digging - soil transfer - unloading - returning the bucket to its original position for digging) takes from 10 (small excavators and light soil) to 30 s ( big cars and heavy soil), it is possible to reduce the cycle time by reducing the time of filling the bucket, combining the turn of the bucket for unloading with its rise to the unloading height, combining the end of the turn with the beginning of unloading the soil (especially when unloading to the dump), combining the return turn of the empty bucket with its lowering to the place of digging in the face.

Saving a few seconds on each cycle, these working techniques have a great effect throughout the entire shift. Advanced machinists cherish, combining operations, up to 5-6 s in one cycle.

6. Strive to reduce unproductive downtime of the excavator associated with the maintenance of the machine, cleaning the bucket, refueling with fuel and lubricants, etc.

The technical condition depends on how timely and carefully the driver conducts Maintenance, lubrication, adjustment of units and minor repairs excavator. You can only work on a fully prepared and serviceable machine.

The time spent on moving the excavator in the face can be reduced by choosing the minimum path for moving and maneuvering the machine, as well as increasing its speed.

The excavator bucket must be cleaned regularly, as soil adhering to the inner walls and bottom of the bucket reduces its capacity. However, it is better to carry out cleaning during the planned downtime of the excavator (during refueling, scheduled maintenance, etc.) or when technological downtime machine (slaughter preparation), as well as possible organizational downtime (lack of vehicles).

Fill the excavator with fuel and oil before the start of the work shift. Refueling is best done during planned stops.

7. Use the power of the excavator and its design capabilities as fully as possible based on the specific working conditions in the face. So, if the soil allows and the engine power is sufficient, it is necessary to dig with the maximum possible thickness of the chips. This will make it possible to shorten the path of the bucket, and consequently, the digging time.

8. Maintain in good condition cutting parts of the bucket (teeth or solid cutting edges for buckets without teeth). They must be sharp and not damaged. It is necessary to carry out preventive maintenance of the cutting parts of the bucket in a timely manner and restore their original dimensions.

You also need to watch correct installation the cutting angle of the bucket in relation to the ground, since the effort expended on digging the soil depends on this. Wrong set angle cutting the bucket leads to unproductive overload of the excavator engine. For normal soil development, it is recommended to set an angle of 25-45° between the upper surface of the teeth and the soil surface. For a cable-driven excavator, this is achieved by changing the place where the bucket is attached to the handle. On a hydraulic machine, the cutting angle is set by tilting the bucket using a hydraulic cylinder.

9. Organize the rational movement of vehicles and loading places with the help of pointing poles, restrictive bars, etc.

10. Carefully unload from the bucket, do not allow the bucket to touch the dump truck body.

11. Ensure that the full working cycle of the excavator (digging - turning the bucket to unload - unloading - returning the bucket to its original position) is within 11-19 s when digging light soils of the C-1] group) with an angle of up to 90 ° and 14-30 s when digging medium and heavy soils (W ~! W group) with the same turning angles (smaller seconds refer to excavators with a smaller bucket capacity).

12. Fully (but not excessively) load vehicles, as underloading reduces the efficiency of its use, and overloading leads to vehicle breakdowns. To do this, the excavator operator must know how much soil is placed in the body of dump trucks of various brands.

13. Notify drivers vehicles by using sound signal about the end of loading, in order to ensure the timely departure of the loaded transport and the entrance of the empty one, and, therefore, about smooth operation excavator.

The size and shape of the face depends primarily on the size of the type of excavator and the size of its working equipment and type of vehicles. So, for an excavator with dragline equipment, equipped with a long boom, the bottom has big sizes in area than that of an excavator equipped with a straight shovel, the maximum bucket distance of which is small. The smallest bottomholes, as a rule, are found in small bucket and mounted shovel excavators.

But the size of the face also depends on the size of those earthworks that need to be built. There is a direct relationship between the size of structures, the dimensions of the excavator and its operating parameters (bucket capacity, power, etc.). The more significant excavation, the more powerful and larger excavators are required for them.

When starting to work in the face, the operator must think in advance how to achieve the highest productivity on the excavator in these specific conditions, and prepare the machine for work accordingly.

Apart from general requirements and techniques that apply to all excavators in general, excavators of each type with specific working equipment (front shovel, backhoe, etc.) require certain specific methods and organization of work in the face for high-performance work. These issues are addressed in the following chapters.

You just have to sit at the "helm" for the first time mining excavator or bulldozer? Of course, experience comes with time, but you can speed up this process by using the knowledge of more experienced machinists.

Users of the Excavator Ru Forum gave some advice to those who are just starting to comprehend the wisdom of mining.

The work of an excavator in a quarry:

1. If there is a risk of stumbling upon a monolith or permafrost, when collecting soil, move the bucket at a small angle to the horizon (as if you are cutting the soil) - then unwanted contact will not occur with the entire area of ​​\u200b\u200bthe bucket, but only with the tip of the crowns.
2. Keep a comfortable bottomhole height and do not change it significantly during operation.
3. Watch out for the "hangs". Don't forget that rocks can roll from above and hit the headlights of the dump truck.
4. Keep an eye on the entrance so that the dump truck does not run into stones. If possible, it is best to work most of the time without the help of a bulldozer.
5. Large stones must be loaded into the body very carefully, especially the first bucket. If the dump truck has a tailgate, then think about whether such stones will get stuck when unloading.

Work better slowly but surely!

Good relationships with colleagues are important in any job. And if your work functions are associated with strict observance of safety regulations, then this is doubly important. So, how best to correct the actions of dump truck drivers (sometimes very capricious)?

Interaction with quarry equipment operators:

1. Set up a few large stones on the sides of the check-in borders - the driver of the dump truck will drive up exactly the way you need to convenient operation.
2. To prevent dump trucks from approaching the excavator closely, you need to press the horn button in time. If the driver still does not keep the distance, make a barrier of several small stones, placing them under the track.
3. Another option is to fill the entrance area with a trifle. And the wheels of the dump truck will not pierce, and the driver will guess that it is enough to drive.
4. Make a "pit" for the crusher and work around it. The main thing at the same time is to have at your disposal a long arrow and a handle.

You can take care of the convenience at work yourself!

Rely on the "serviceman", but do not make a mistake yourself. A few tips on how to keep undercarriage tracked vehicles clean.

How to clean the undercarriage:

1. A piece of a spring sharpened on an emery wheel can be welded to a pipe of small diameter (15 or 20 mm) - it is much easier to clean the "hodovka" with such a device than with a shovel.
2. Pressurized steam - but for this you will have to get special equipment.

And a few more tips.

Track tension check:

1. Rotate the platform 90 degrees (across the tracks) and "push up" so that the track sags (but don't push too high). Place the bucket as follows: position the bucket teeth parallel to the ground, and the arm hydraulic cylinder rod should be extended half way. After performing all the above manipulations, measure the sagging of the track (as the distance from the track rollers located in the middle of the track to the track). By the way, the standard is 10-15 cm.
2. Second option. Pull the "slack" on one of the tracks forward, then put the block on the sloth and the support roller. The distance from the greatest sag to the bar should be 10-30 mm. Then repeat the steps for the other caterpillar. This work should be done on a flat, firm surface.

Advice was given: HITACHIST, zemlekop-54, Nafis, uncle bone, naufal, techrep, KOTYARA1967, naufal.

Hydraulic excavators are a fundamental technique in the production of many types of earthmoving or when performing on the movement of masses of various kinds of soils. According to statistics, the growth in the excavator market is 7-8% annually. At the same time, imports of equipment from abroad show a good growth of 40-45% of this number. It turns out that the entire market earthmoving equipment divided between Russian and foreign manufacturers.

The question of which excavator is better when choosing is not answered unequivocally by any expert. The arguments are simple: Russian technology cheaper, and the western one is more reliable. Therefore, let's try to understand the question: neat work equipment breaks less often, but ignorance of control functions will lead to an unambiguous breakdown. You can download the manual for excavator operators at.

Import equipment management

Now let's answer the detailed question: how to operate an excavator imported production so as not to break it. To begin with, let's define what hydraulic excavator you won’t have it - large or small, you will need knowledge and skills to manage it, but physical strength will definitely not be required. There will be a dashboard, like a good one passenger car, which will provide the necessary information about all the parameters of the machine. It contains:

• Tachometer;
• Oil pressure indicator;
• Engine temperature;
• Charging excavator batteries;
• Alarm indicator - warning about overheating;
• The level of working fluids of the excavator;
• Hours counting board;

Two joysticks will share the functions of controlling the excavator, one will be responsible for the movement of the excavator in space and the movement of the near part of the boom, the other for the operation of the manipulator boom and bucket. As difficult as the job may be, control will require practice, which can be obtained on a computer with a simulator program for this type of excavator.

It is necessary to know that Various types excavators, depending on the manufacturer, have individual control schemes.

Management of domestic equipment

Excavator control features Russian assembly will differ from imported machines by the presence of up to six hydraulic distributors directly connected to the hydraulic cylinders of the excavator boom arm and the bucket control mechanism.

Behind forward movement technicians will respond with two pedals and levers for tracked vehicle or a wheel for the chassis on a pneumococcus. Well theoretical training And Internship will be the answer to the question how to operate an excavator domestic assembly.

Safety

When working on excavators imported and domestic production you must read the safety instructions developed specifically for a particular model.

Before starting the first work, it is necessary to familiarize yourself with the meaning of the special information located on the body and units of the excavator. Warning labels on the machine will be present in all dangerous places, and have accompanying inscriptions that indicate the level and degree of possible danger:

• A WARNING will signal that a potential hazard has occurred whereby failure to take action will result in potentially minor or moderate injury.
• WARNING is intended to draw attention to the potential for dangerous situation, which can lead to serious injury or death if not taken in time necessary measures as a precaution,
• DANGER, indicates the imminence of a particularly dangerous situation, as a result of which the neglect of safety measures will lead to serious injury or death.

The plates available at all equators use drawings and inscriptions for visual warning and are mandatory. Safety precautions when working on crawler excavator described

Construction is quite difficult process, which implies quite a lot various kinds Job. Among them, a special place is occupied by tillage, which is carried out in most cases by excavators.

These mechanisms are quite expensive, so not every consumer can afford to buy it. An alternative is the usual rental of an excavator for a certain time, which makes it possible to complete all the tasks.

Preparatory work

The excavator is very complex mechanism, so its management will not be easy and requires certain skills. Before proceeding to this process follow a few simple guidelines:

1. First of all, you need to familiarize yourself with the system of the machine itself. It is necessary to single out the working bodies and structures to control them.
2. Before starting work, be sure to check that the excavator is working. To do this, it should be inspected for damage and other similar defects.
3. After that, be sure to read the operating instructions. This will help you deal with all the buttons, levers and other elements.

Getting Started

The excavator control process should begin with the following simple recommendations:

• First you should get behind the wheel and start the engine so that it warms up for a certain time. Also, make sure that all working parts are on the ground.
• After that, let go parking brake and try to move forward on the excavator. In this case, it is advisable to immediately use only low speeds in order to get used to the operation of the device.
• The next step is to study the work of the main organs. They can be controlled both with the help of levers and joysticks. Raise the bucket slowly, understanding in which direction it should move.

To try to dig, you should put the excavator in the rear position and place it on special supports. After that, you can try to control the boom and work with the soil.

Please note that excavators can radically differ from each other, both in power and in the control system. If you want to learn how to work efficiently with such machines, then it is advisable to take special courses where you can gain experience. Only Full time job with an excavator will allow you to feel it correctly and perform the most difficult tasks.