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Previously, when automatic washing machines were just coming into use, spinning the laundry in them was especially pleasing to the owners. No joke - technology freed them from such a tedious process. Then no one thought about how fast the drum rotated. The machine still squeezed much better than a man. Now manufacturers are trying to make sure that the laundry wrung out in the washing machine can be hung up almost immediately in the closet. True, increasing the speed of rotation of the drum - the method by which they are trying to achieve this, in our opinion, is very doubtful. Let's try to figure out whether the washing machine needs "space" speeds?

Spinning in the washing machine: observe speed mode!

The final stage of washing - spinning has always been one of the most difficult stages. As the saying goes, "the last fight is the most difficult one." Women, who in our country, as a rule, were engaged in washing, it was at this stage that they called for help from their husbands and children: one cannot squeeze a heavy duvet cover.

Fortunately, times have changed. Now, in fact, none of the family members is engaged in washing in the house. Preparing and sorting the laundry doesn't count. The process itself is at the mercy of automation - a modern washing machine has settled in our apartments.

We can talk for a long time about what programs and functions have washing machines of different price categories and manufacturers, how they differ from each other, or vice versa - similar. Sometimes, on specialized Internet forums or even just in the subway, there are disputes about which programs a washing machine needs, and which one can be completely dispensed with. All debaters, however, agree on one thing - without spinning, an automatic washing machine would immediately lose its appeal.

Classes and spinning technology

Washing machines by spin class are divided into 7 categories, which are designated by the Latin letters A, B, C, D, E, F, G. The awarding of one category or another depends on the residual moisture of the laundry, which is measured as a percentage. It is determined simply - dry laundry is weighed before washing, and after it the wrung (wet) is weighed. The dry weight is subtracted from the wet weight, and the resulting difference is divided again by the dry weight. The quotient is multiplied by 100 percent - the desired result is obtained.

The residual moisture of the laundry in spin class A must not exceed 45 percent. B-class allows residual moisture up to 54 percent, C - up to 63, and D - up to 72. Models that squeeze worse are now practically not found on sale.

I must also say that you should not be "afraid" of washing machines whose spin class is lower than A (such, by the way, the majority), the difference between classes A and B or even C - although it looks significant in percentage, in practice it is not so great. Of course, when spinning the C-class, it will take a little more time to dry the laundry, but the quality of the wash (what, in fact, you need a washing machine for) will obviously not get worse.
But the spin class depends not only on the degree of residual moisture in the laundry. One of its criteria is also the number of revolutions that the drum of the washing machine can complete in a minute. The more of them, the higher the chances of the manufacturer to proudly announce that the spin class of their unit is A. In most models offered on the market today, the number of revolutions is 1000 - 1200 per minute. However, there are units that "accelerate" to 1600, 1800 and even 2000 rpm (for example, the Gorenje WA 65205 model).

Is this good or bad? Are such "cosmic" spin speeds needed, or will the usual, "earthly" ones be enough? To answer these questions, it is necessary, first, to understand how the spinning process itself actually occurs.

In principle, it is not difficult at all. After the end of rinsing, the used water is drained off using the pump. Then the spin itself begins. The number of revolutions of the drum gradually increases, water from the laundry, obeying the centrifugal force, enters the tank through the holes in the drum, while the pump periodically turns on and it is removed to the sewer. The engine (and hence the drum) reaches its maximum speed at the end of the spin cycle, and only for a few minutes (usually no more than two).

Expert opinion

Returning to the question of the need for "high speeds" of rotation of the drum, it should be noted that until recently in Russia there was a steady opinion that what more revolutions per minute during spinning it is able to complete the drum of the washing machine, the better and more reliable the entire unit as a whole. In fact, this is not the case. In order not to be unfounded, we decided to turn to practitioners - the specialists of one of the largest Moscow networks for the repair of household appliances "A-Iceberg". Our questions were answered by Andrey Belyaev, the manager of the department for the repair of large household appliances, whose work experience in this area is 11 years.

-Andrey Viktorovich is it possible to assert that the number of revolutions of the drum of the washing machine during the spin cycle is indirectly an indicator of technical excellence, greater reliability of the model, and therefore more long term her service?

- No, there is no direct relationship between the number of drum revolutions, the service life and the reliability of the machine. Each model has its own service life set by the manufacturer, and he also undertakes warranty service its equipment, produces spare parts. And even machines with 400 - 600 revolutions per minute (now these are usually narrow and compact models) may well work for more than ten years. True, the service life, which is announced by the manufacturer, is also subject to revision. For example, at the Ariston company, the service life of the machines decreased from 10 years to 7. At the same time, the manufacturer did not provide any official explanations. But many experts believe that this is due to an increase in the number of complaints about the operation of units of this brand, and in fact this indicates a decrease in product quality and the manufacturer's “safety net”. It is worth noting that a similar trend (decrease in quality) is now observed in many companies that produce household appliances... This can be explained by the desire of some companies to reduce the cost of their products, to make them available to a wide range of buyers. Because of this, many resort to buying cheaper components - as a result, quality suffers.

And aren’t they put, for example, reinforced bearings and other specially prepared components on units with a high drum speed?

- They do, but, alas, this does not lead to a serious increase in the working life of the same bearings. In principle, one can even say the opposite - the lower the number of revolutions, the longer some units of the washing machine can work, which is reflected in the service life of the entire unit as a whole. But still, I will emphasize once again that the duration of the washing machine's service and the number of drum revolutions during spinning are not related. Rather, how many years your "automatic washerwoman" will work depends more on the quality of the components. For example, since we are talking about bearings, some companies order them in Poland, but the quality of bearings from this country is worse than, for example, from Sweden, SKF. So it is advisable to choose the machine according to the configuration, and not according to the number of drum revolutions during spinning.

What number of revolutions makes the machine a "high-speed" unit?

- Today, such models are considered to be capable of wringing out with a drum rotation frequency of more than 900 rpm.

Does high-speed washing machines have special devices to reduce the inevitable noise and vibration? And in general, how does a "high-speed" machine differ from a conventional one, except, in fact, the drum rotation speed?

- Differs, for example, in the presence of a processor board that allows the user to independently change the number of drum revolutions while setting the washing program. In addition - the presence of reinforced shock absorbers and suspension springs. As a rule, more modern ones are installed on such models. asynchronous motors... Recently, cars with a new type of motor appear in general - it is "directly" connected to the drum. This avoids the belt drive, one of the main sources of noise during spinning. For example, LG already has such machines.

And yet, there is a direct relationship between the maximum drum speed and the spin class of the washing machine. The faster the drum spins, the drier the laundry is, the less its residual moisture, which means the higher the spin class. Where is the limit, how much more can you increase the rotation speed - 1600, 1800, 2000, maybe 2500 rpm perfect option?

- Do not increase the number of drum revolutions indefinitely. If you do this, then the laundry will simply tear: microscopic holes will turn into small, small into large, folds on synthetics can become creases

What is the optimal speed?

- More than 1000 rpm is not needed. All the same, for washing wool, silk, fine fabrics, the limit is 500 revolutions. Synthetics cannot be wrung out at a speed of more than 900 revolutions (this is the maximum!). For some things, spinning is generally contraindicated. And as for the notorious residual moisture of the laundry, if you compare it at 500 and 1000 rpm, the difference will be significant, and at 1000 and 1200 rpm it is almost invisible. The residual moisture content of 45% or less (which some manufacturers strive for) is achieved by complex and expensive technical solutions.

In which type of machine is it easier to "organize" high spin speeds: front-loading or top-loading?

- On the one hand, the reliability of "vertical" washing machines is theoretically higher than "frontal" ones. This is due to the fact that in them the drum is fixed on two sides, and not on one, as in front-loading devices. Naturally, this affects the service life of other parts, for example, bearings, which in "vertical" devices are "spaced" to different sides (in accordance with the drum mountings). But on the other hand, the level of vibration during spinning in such washing machines, in general, is higher due to the design features. Therefore, now there is not much difference between the types in which one is more suitable for spinning at high speeds.

Are there any alternative methods of spinning the laundry?

- It is difficult to call them alternative, rather it is a symbiosis of methods in which you can wring out the laundry at the "sane" drum speed, and then dry it using a tumble dryer or a washing machine with a dryer. But there are downsides to this. For example, there may not be enough space to install a tumble dryer. After all, the bathrooms and kitchens in the apartments of many people are very small, and not everyone wants to put such a unit in the hallway or in the living room. Washing machines with dryers are distinguished by their small capacity. As a rule, you can dry in them no more than 3 kilograms of linen, and given that you can usually wash 5-6 kilograms, it turns out that the drying process will take two stages, and this is additional time, and electricity consumption. By the way, many dryers do not use electricity very economically at all. Basically, their energy consumption class is higher than C. In addition, you need to know that the laundry that is constantly dried "machine" wears out faster. This is due to the fact that no matter how hard the manufacturers try, no matter how they improve the drying process, the fibers of fabrics do not always warm up evenly. In some places, a banal overheating occurs, the thing dries up and the fabric becomes thinner.

Conclusion

Well, it seems to us that now everything that is called has fallen into place. The desire of the manufacturer to capture the imagination of the buyer is understandable. After all, equipment must be sold in order to make a profit. But the catch is that in the process of washing automation, now, perhaps, almost everything has been invented that has allowed the modern development of technology. Breakthroughs and revolutions are not worth waiting for. So the "poor" firms that produce household appliances have to come up with something out of nothing to attract buyers to their new models. "High-speed" pressing is just one of this series.

We hope that those who used to pay attention to this parameter - spin speed when buying a washing machine - will reconsider their approach after our material. Of course, we do not urge you not to be interested in how the machine squeezes. But chasing "centners per hectare" - a large number of revolutions of the drum during spinning is certainly not worth it. Rest assured - 1000, maximum 1200 revolutions per minute is enough for high-quality spinning of terry robes, sheets and towels. We do not recommend squeezing everything else at such speeds.

There is, of course, such a thing as prestige. For some, it is especially important that they do everything better than others. But believe me, if you buy a Swiss washing machine Schulthess (for example, the Spirit XL 1800 CH model), for 75,000 rubles, then it will amaze neighbors and friends with its cost alone, and, perhaps, design. Of course, you can squeeze out something unnecessary at 1800 rpm, but only if you really don't need it.

In general, the choice, as always, is yours. We just wish it was meaningful.

In materials about cars, the expressions "high revs", "high torque" are often used. As it turned out, these expressions (as well as the relationship between these parameters) are not clear to everyone. Therefore, we will tell you more about them.

Let's start with the fact that the engine internal combustion It is a device in which the chemical energy of the fuel combusted in the working area is converted into mechanical work.

Schematically, it looks like this:

Combustion of fuel in the cylinder (6) causes the piston (7) to move, which in turn causes the crankshaft.

That is, the expansion and contraction cycles in the cylinders drive crank mechanism, which, in turn, converts the reciprocating motion of the piston into rotational motion of the crankshaft:

What the engine consists of and how it works, see here:

So, essential characteristics of the engine are its power, torque and revolutions at which this power and torque are achieved.

Engine speed

The commonly used term "engine speed" refers to the number of revolutions of the crankshaft per unit of time (per minute).

Both power and torque are not constant values, they have a complex dependence on engine speed. This relationship for each engine is expressed by graphs similar to the following:

Engine manufacturers strive to ensure that the engine develops maximum torque in the widest possible range of revolutions ("the torque shelf was wider"), and the maximum power is reached at the rpm closest to this shelf.

Engine power

The higher the power, the great speed develops auto

Power is the ratio of the work done over a period of time to that period of time. In rotary motion, power is defined as the product of torque and angular velocity rotation.

Recently, engine power is increasingly indicated in kW, and previously traditionally indicated in horsepower.

As can be seen in the above graph, maximum power and maximum torque are achieved at different crankshaft speeds. The maximum power for gasoline engines is usually achieved at 5-6 thousand rpm, for diesel engines - at 3-4 thousand rpm.

Power graph for diesel engine:

In practical terms, power affects the speed characteristics of a car: the higher the power, the greater the speed the car can develop.

Torque

Torque characterizes the ability to accelerate and overcome obstacles

Torque (moment of force) is the product of force per lever arm. In the case of a crank mechanism, the given force is the force transmitted through the connecting rod, and the lever is the crankshaft crank. The unit of measurement is Newton meter.

In other words, torque characterizes the force with which the crankshaft will rotate, and how well it will overcome the resistance to rotation.

In practice, the high engine torque will be especially noticeable during acceleration and when driving off-road: at speed the car accelerates more easily, and off-road the engine can withstand loads and does not stall.

More examples

For a more practical understanding of the importance of torque, we will give a few examples on a hypothetical engine.

Even without taking maximum power into account, some conclusions can be drawn from the torque graph. Let's divide the number of revolutions of the crankshaft into three parts - these will be low, medium and high revolutions.

The graph on the left shows a variant of the engine that has a high torque at low revs (which is equivalent to high torque at low speeds) - with such an engine it is good to drive off-road - it will "pull" out of any quagmire. The graph on the right shows an engine that has high torque at medium revs (medium speeds) - this engine is designed for use in the city - it allows you to quickly accelerate from traffic lights to traffic lights.

The following graph characterizes an engine that provides good acceleration even at high speeds - this engine is comfortable on the track. The graphics are closed by a universal engine - with a wide shelf - such an engine will pull it out of the swamp, and in the city it allows you to accelerate well, and on the highway.

For example, a 4.7-liter gasoline engine develops maximum power 288 h.p. at 5400 rpm, and a maximum torque of 445 Nm at 3400 rpm. A 4.5-liter diesel engine installed on the same car develops a maximum power of 286 hp. at 3600 rpm, and the maximum torque is 650 Nm with a "shelf" of 1600-2800 rpm.

The 1.6-liter X engine develops a maximum power of 117 hp. at 6100 rpm, and the maximum torque of 154 Nm is achieved at 4000 rpm.

The 2.0-liter engine delivers a maximum power of 240 hp. at 8300 rpm, and a maximum torque of 208 Nm at 7500 rpm, being an example of "sportiness".

Outcome

So, as we have already seen, the relationship between power, torque and engine rpm is quite complex. In summary, we can say the following:

torque responsible for the ability to accelerate and overcome obstacles,
powerresponsible for the maximum speed of the vehicle,
a engine speed everything is complicated, since each value of revolutions has its own value of power and torque.

And in general, everything looks like this:

high torque at low rpmgives the car traction for off-road driving (such a distribution of forces can boast diesel engines). In this case, the power may become narrower secondary parameter - remember, at least, the T25 tractor with its 25 hp;
high torque (or better - "torque shelf) at medium and high revsmakes it possible to accelerate sharply in city traffic or on the highway;
high power engine provides high top speed;
low torque (even at high power) will not allow the engine to reach its potential: being able to accelerate to high speed, the car will reach this speed for an incredibly long time.

Almost every driver is well aware that the resource of the engine and other vehicle components directly depends on the individual driving style. For this reason, many car owners, especially beginners, often think about which revs are best to drive. Next, we will consider what engine speed you need to keep taking into account different road conditions during the operation of the vehicle.

Read in this article

Engine resource and rpm while driving

Let's start with the fact that competent operation and constant maintenance of optimal engine speed allows you to increase the engine life. In other words, there are modes of operation when the motor wears out the least. As already mentioned, the service life depends on the driving style, that is, the driver himself can conditionally "regulate" this parameter... Note that this topic is the subject of discussion and controversy. More specifically, drivers are divided into three main groups:

the first are those who operate the engine at low speeds, constantly moving "vnatyag".
the second should include those drivers who only periodically spin their engine up to above average rpm;
the third group is considered to be car owners who constantly maintain the power unit in a mode above average and high engine speeds, often driving the tachometer needle into the red zone.

Let's understand in more detail. Let's start with a low-end ride. This mode means that the driver does not raise the revs above 2.5 thousand rpm. on gasoline engines and holds about 1100-1200 rpm. on diesel. This driving style has been imposed on many since the days of driving schools. Instructors authoritatively argue that it is necessary to drive at the lowest rpm, since in this mode the greatest fuel economy is achieved, the engine is least loaded, etc.

Note that during driving courses, it is advised not to turn the unit, since one of the main tasks is maximum safety. It is quite logical that low revs in this case are inextricably linked with driving at low speeds. There is logic in this, since a slow and measured movement allows you to quickly learn how to drive without jerks when changing gears on cars with manual transmissions, teaches a novice driver to move in a calm and smooth mode, provides more confident control over the car, etc.

It is obvious that after receiving driving license this driving style is further actively practiced in your own car, growing into a habit. Drivers of this type start to get nervous when the sound of a spinning engine starts to be heard in the cabin. It seems to them that an increase in noise means a significant increase in the load on the internal combustion engine.

As for the engine itself and its resource, too "sparing" operation does not add to its service life. Moreover, everything happens exactly the opposite. Imagine a situation when a car is moving at a speed of 60 km / h in 4th gear on smooth asphalt, rpm, say, at around 2 thousand. In this mode, the engine is almost inaudible even on budget cars, fuel is consumed minimally. At the same time, there are two main disadvantages in such a ride:

there is almost no opportunity to accelerate dramatically without switching to downshift, especially on "".
after changing the topography of the road, for example, on inclines, the driver does not downshift. Instead of shifting, he simply pushes harder on the gas pedal.

In the first case, the motor is often outside the "shelf", which does not allow the car to be quickly accelerated if necessary. As a result, this driving style affects overall driving safety. The second point directly affects the engine. First of all, driving at low revs under load with a strongly pressed gas pedal leads to detonation of the engine. This detonation literally breaks the power unit from the inside.

In terms of consumption, the savings are virtually nonexistent, as pressing the accelerator pedal harder in overdrive under load causes the air / fuel mixture to richer. As a result, fuel consumption increases.

Also driving "vnatyag" increases engine wear even in the absence of detonation. The fact is that at low speeds the loaded rubbing parts of the motor are not sufficiently lubricated. The reason is the dependence of the performance of the oil pump and the pressure it creates engine oil in from all the same engine speed. In other words, sleeve bearings are designed to operate under hydrodynamic lubrication. This mode involves supplying oil under pressure to the gaps between the liners and the shaft. This creates the desired oil film, which prevents wear of the mating elements. The efficiency of hydrodynamic lubrication is directly dependent on the engine speed, that is, the more revolutions, the higher the oil pressure. It turns out that with a high load on the engine, given the low speed, there is a high risk of severe wear and damage to the liners.

Another argument against driving at low revs is the reinforced engine. In simple words, as the speed rises, the load on the internal combustion engine increases and the temperature in the cylinders rises significantly. As a result, part of the carbon deposit simply burns out, which does not happen with constant operation at the bottom.

High engine speed

Well, you say, the answer is obvious. The engine needs to be spinned harder, since the car will confidently respond to the gas pedal, it is easy to overtake, the engine will be cleaned, fuel consumption will not increase so much, etc. This is true, but only in part. The fact is that constant driving at high revs also has its drawbacks.

High turnovers can be considered those that exceed the approximate figure of about 70% of the total number of available for gasoline engine... The situation is slightly different, since units of this type are initially less revolving, but have a higher torque. It turns out that high revs for engines of this type can be considered those that are behind the "shelf" of the diesel engine torque.

Now about the engine resource for this driving style. Strong cranking of the engine means that the load on all its parts and the lubrication system increases significantly. The temperature indicator also increases, additionally loading. The result is increased engine wear and increased risk of engine overheating.

It should also be borne in mind that at high speed modes, the requirements for the quality of engine oil increase. Lubricant should provide reliable protection, that is, meet the declared characteristics of viscosity, oil film stability, etc.

Ignoring this statement leads to the fact that the channels of the lubrication system can clog with constant driving at high speeds. This happens especially often when using cheap semi-synthetics or mineral oil... The fact is that many drivers change oil not earlier, but strictly according to the regulations or even later than this period. The result is the destruction of the liners, disrupting the operation of the crankshaft, and other loaded elements.

What rpm are considered optimal for the motor

To preserve the engine's resource, it is best to drive at such speeds, which can be conventionally considered average and slightly above average. For example, if the "green" zone on the tachometer assumes 6 thousand rpm, then it is most rational to keep from 2.5 to 4.5 thousand rpm.

In the case of atmospheric internal combustion engines, designers are trying to fit the torque shelf precisely in this range. Modern turbocharged units provide confident traction at lower engine speeds (the torque shelf is wider), but it is still better to spin the engine a little.

Experts say that the optimal operating modes for most motors is from 30 to 70% of the maximum speed while driving. Under such conditions power unit minimal damage is done.

Finally, we add that from time to time it is advisable to spin up a well-heated and serviceable motor with quality oil 80-90% when driving on flat road... In this mode, it will be enough to drive 10-15 km. Note that this action does not need to be repeated often.

Experienced car enthusiasts recommend turning the engine almost to the maximum once every 4-5 thousand kilometers traveled. This is necessary for various reasons, for example, so that the cylinder walls wear out more evenly, since with constant driving only at medium speeds a so-called step can form.