What makes the spark plugs. Types of automotive spark plugs - their device and malfunction

In gasoline engine internal combustion (DVS) For ignition, compressed by the piston, the fuel and air mixture uses an element called - Ignition Candle. Invented her Robert Bosch in the distant 1902 after which, the company of the same name introduced it in.

What is her device?

The basic device of the spark plug is about the same in any company producing it. This is a metal housing, the electrodes whose number can vary depending on the brand, a ceramic insulator and a central contact rod passing through it. The further distinguishes begin.

The central contact rod, for example, may have a tip in the form of a flat platform. But may have U or V-shaped groove. It may be pointed - in the event that it is made of iridium as in Denso's candles. They even have a side electrode has a special form profile. This company produces the most, perhaps, reliable candles - Iridiyevo-platinum.

W. separate models The side electrode may not be generally - in particular, SAAB engineers have developed a motor in which the piston itself has a pointed ledge, the function of which is the same as the side electrode. When the piston is as close as possible to the upper dead point, there is a spark between it and the central electrode, igniting the compressed fuel and air mixture.

Already mentioned two and more side electrodes also change in best side Work modes and motor operation parameters. At the same time, the requirements for working gaps that do not recommend changing or somehow touching or bend, but only strictly retaining the factory parameters of their manufacture are increasing.

At the same time, the principle of operation of the candle with two or more electrodes is simple, no technical tricks are required for its stable operation: when, as the electrode is produced, the sparks "eaten", it starts, it automatically appears on the non-worked electrode, and the process of operation of the OBS continues without interruptions.

The metal housing at the bottom of the thread for screwing into the cylinder head (GBC) has a flat or conical ring-shaped platform. In the candles with a flat venue in the kit there is a crimp ring-washer made of soft metal, which prevents the breakthrough of a compressed fuel and air mixture or combustion products. In the candles with a conical profile after a thread in such a ring, no need the conical profile is reliably cleaned the top of the combustion chamber.

Central insulators in all models make heat-resistant ceramics. It is on it that the markings are applied with the type, the name of the manufacturer, etc. Inside, between contact for the wire and a core with a central contact, a resistor is placed, the main function of which is the suppression of radio cells that occur at the time of the spark discharge. Taking into account the development of radio and telecommunications and their introduction to the car system, including electronic control Injection, the placement of such a resistor has become mandatory in the spark plug device.

In that part, which is screwed into the GBC, the central insulator has the form of a gradually narrowing cone - this is done in order to more effectively distinguish heat, not allowing it.

View of modern candles

A variety of technical solutions in the development and production gasoline engines Internal combustion gave rise to many candle models for them. Depending on the fuel used for the machine, the compression ratio in the cylinder, the ignition control method (mechanical, using a distorter, or electronic), can be divided into the following types.

Types of candles

They are divided into several characteristics:

1. A calic number.
2. The number of electrodes.
3. Spark gap.
4. Temperature range.
5. Service life.
6. Characteristics of heat resistance.

In addition, some of the spark plugs of different years of release of the same company may differ along the length of the thread skirt: early car models have a smaller thickness of the cylinder heads that were made from cast iron and, respectively, the thread is needed shorter. With the transition to the GBC from aluminum alloys, their thickness increased, which means - and the length of the thread in it also became greater.

An experienced motorist at the beginning will always pay attention to a calil number that shows the pressure with a glow effect, that is, the continuation of the engine operation after breaking the ignition circuit when the motor heated to critical values \u200b\u200bcontinues to operate.

At the same time, the use of a candle with a calil number is more recommended to use even permissible, with the exposed - the operation of the engine is prohibited! Otherwise, the unlucky driver will quickly collide with the problem of burning pistons, valves and with breakdown of cylinder head laying.

For high-quality and stable sparking in the last two dozen years, we produce candles with two, three and even four side electrodes.

But the stability of work can be achieved in other way: the location of the auxiliary elements playing the role of these electrodes, on the insulator of the candle. There are several ring wandering around the central electrode of electrical discharges, and thus, the likelihood of the engine operation is significantly reduced.

Brist Sports Candle with Intermediate Electrodes on Isolator

We give a few more important moments In the characteristics of candles:

• Violation of such a parameter, as a spark gap, will also adversely affect the operation of the motor;
• No less important thermal resistance, its temperature range, meaning the heating of the part, which is immersed in the space between the piston and the cylinder head. The temperature range inside the working part is normally under 500-900⁰. The output beyond this range means lowering the resource. In particular, in all types of spark plugs, a decrease in temperature leads to a rapid rise in Nagara;
• In a normally adjusted engine, efficiency depends on the run and amounts to about 30,000 km for candles operating on the classic ignition scheme, and 20,000 - to electronic. However, at the highest price (but also in the most reliable) candles of DENSO service life - up to 5-6 years. Or, in other words, they will provide mileage without replacement, subject to standard operation for about 150,000 - 200,000 kilometers. True, the requirements for maintaining modes according to the instructions are tightened. These requirements include the use of fuel with octane number In no case below the recommended, and their installation is strictly according to the rules. In particular, they are not allowed to tighten them into the cylinder head with effort above or lower than recommended, which may entail reduced to all of their advantages;
• The heat parameter shows the relationship of the engine modes and operating temperature Candles. It increases the size of the thermal cone, adhering to the size of the thermal cone, and, however, the recommended value of 900 degrees. The way out of these boundaries increases the risk of vibil ignition.

Precious metals in candles design

The gradation of species depends not only on the stated parameters. Describing the performance of the spark plug, it is necessary to take into account since what material the tips of the electrodes are made.

The cheapest candles are nickel. The simplicity of the design causes a short service life, so their replacement is often done, after 15-18 thousand mileage kilometers. Although in the conditions of the city, given the irregularities of operation (standing with a working engine in traffic jams, frequent alternation of acceleration and braking on traffic lights) This mileage can be safely divided into two, so that the time of operation of nickel candles is no longer more than a year.

Platinum candles are made platinum attacks, which increases their life to 50,000 kilometers. Look at the cost of platinum in any exchanger - and you will understand why these attacks make them as expensive.

IN iridiyev Candle Already two precious metal: Iridium in the form of a naughty on the edge of the central electrode and platinum - on the side. Given the cost of iridium, the price of them compared to nickel increases by 50-60%. But specifications Spark plugs with iridium are such that it is already from 60 to 200 thousand kilometers away with them.

Such candle parameters like: thread diameter; number head number under it; Skirt length with thread; The gap between the electrodes also belongs to their technical characteristics.

Conclusion

Progress does not stand still. New technologies allowed, for example, to bring the degree of purification of metals for electrodes to 99.999%. Iridium, platinum and even nickel such cleanliness are able to increase the service life of the spark plug by another 15-18%, in the example, we will deliver Denso. In addition, engineering thought continued their development, offering the factory and the forkar type of spark production, which made the work of the motors even more stable.

As for the inevitable in this case, the price increase is the possibility in the process of operation of the car as much as possible to look under the hood already justifies the purchase of each spark plug even for 10-20 dollars per piece.

Spark plugs are present in each car and each of the car owners at least once in his life tried to "figure out" with them on their own. In the operation manual, the machine is always recommended by the manufacturer. It is worth understanding what the candles differ of different types and various manufacturers? Is there any difference when replacing one type of candles to others in the machine?

Often, car owners cannot decide on the choice, buy cheap candles or high-quality

Types and principle of work

Spark plugs ignite the mixtures formed by mixing fuel and air. Depending on the manufacturer, the design of the candles is different, however, two groups can be distinguished. Their types:

• multielectrode spark plugs;
• two-electrode.

The two-electrode devices are equipped with a single side electrode, in contrast to them, multoelectrode candles consist of several side electrodes. The latter justify themselves with a long service time. In the most common spark, there are two electrodes that wear out. The failure of the side electrode is full replacement Candles. The spark in a multi-electrode device comes only on one side electrode, which increases the opening time of the candle.

Spark plugs are different from each other also material. In classic devices, minor electrodes are made of steel. The most expensive candles are equipped with platinum attacks, in addition, the release of plasma-forcar spark plugs began quite recently. The tip of the main electrode is made of alloys consisting of iron, nickel and chromium and copper plugs. The side of the central element often flashes, it must be periodically verified for a malfunction. The insulator is almost always made of ceramics of aluminum composition, carrying temperatures above 1000 ° C. The heat marking of the ignition candles directly depends on the composition and proportion of the various components contained in the insulator.

In addition, the candles differ in the type and long thread, the size of the head.

Ignition candle device

Any candle, regardless of its type and manufacturer, consists of a metal housing, electrodes, a ceramics insulator and the main contact rod. The base of the case covered with a special means of corrosion, upstairs is equipped with a thread embedded in a block of cylinders and a hexagon. A part of the plane that the candle "faces" with the head has a flat or conical shape. If there is a flat reference part for better sealing, the sealing ring is built. In contrast to the first conical top, it seals the hole between the spark plug and the block head. The insulator is made of durable ceramics. The spark plug device is thought out to the smallest detail to avoid electricity leakage in the insulator, ring longitudinal stripes are provided and the technical glaze is applied, part of the hull next to the combustion chamber is made as a cone. FROM inner The main electrode and rod are attached to the isolator. In some models, the gap between them fills the resistor that is preventing. Compounds are tightly sealed by glass mass with high conductor. Next to the central there is a side electrode, which is made of heat-resistant metal and is welded to the case. To reduce the thermal effect, the main electrode is performed from several metals (copper and heat-resistant shell).

Signs of Ignition Candle Fault

Stable work of the candle provides car owner reliable operation of a gasoline power unit. However, problems in the work of candles simply not to avoid. Let's figure out when changing spark plugs:

• the car began to start not the first time, the engine is working with difficulty, "coughs" displeased idling. This is one of the very first signs on the need to check the candles for a malfunction;
• fuel consumption has recently increased significantly, in addition, CO and CH increased in exhaust gases;
• one of the candles all the time is wet from the gasoline falling on it (it will be faulty).
• during the operation of the motor, negative dynamics is manifested (a reduced power or auto is not limited to revolutions).
• "Trojections" appeared (the car pulls into the car during driving, the engine lacks the power).

It is not necessary to wait for it, if there is at least one of the described features, you should take a box with tools and thoroughly check the functioning of the candles. On time not replaced parts can be in as soon as possible Apply a huge damage both the car and the owner's wallet. All manufacturers of the car recommend replacing these parts with the annual maintenance passage.

Methods of diagnosis

The diagnosis of the power unit provides for inspection of candles as an important element of the ignition system. Almost all cars are overseas and domestic production They are easily accessible, car enthusiasts themselves can check them. In order for checking successfully, they are undesirable to be confused and change places relative to cylinders, it is best to consider them in.

There are several ways to check the health of the candle at home. Before removing them, first of all you need to disconnect the wires going to the distributor. To determine which candle stopped working, you can remove them alone and listening to the operation of the engine. A unchanging sound talks about the problem in a disconnected part.

Check sparks

The first method of checking at home is the presence of a spark. Carefully cleaned OT different pollution The candle with the device (probe) is adjusted at a distance with the electrodes. It is covered with wire and adjacent to the metal basis of the power unit. This is done in order to create electrical contact. Check the operation of the candles (the presence and color of the spark) is necessary by the starter included for a couple of seconds. In a normal functioning candle, the spark has a blue color, but if a red color or it is played in a spark, in general, no, it means that the candle is subject to replacement.

Checking multimeter

In the second way, to test the health of the candle is much easier, for this you need a multimeter - a device that is often called a tester. This device checks the presence of either no short circuit. However, the verification of the multimeter does not always exactly indicate a malfunction. Simple in circulation The device has a form understandable for a simple car enthusiast. Checking the candle is carried out as follows: The wires from the device should be on the spark plugs so that the first wire is at the exit, and the other was attached to the base. A spark appears in a workable position, with 4 mm regarding contacts.

Check "Pistol"

The third method of calibration is the most sophisticated - this is a test of a gun. To make it yourself, you need a stand, conducted by such a test under some pressure. Nowadays, you can buy such a device in the store trading in auto parts. Check the candle is needed like this: insert it into and wear a special cap. The main candle after pressing the trigger should respond on the electrodes of sparking and a tanned light bulb. It is worth remembering that the gun, due to the pressure difference in it and in the car, cannot give an exact result. However, the candle does not work when checking the pistol must be replaced soon.

Conclusion

Even small violations and malfunctions from the spark plugs can, with the unscrupulous attitude of the car owner, lead to serious malfunctions in the operation of the machine. It is worth knowing that any driver can do this device. To do everything correctly, you only need to follow the actions described above.

It is time, dear readers, talk about the element that matures the entire car ignition system and no doubt is one of the key in the work of gasoline. Ignition Candle - it is for the sake of sparks that occurs between its electrodes, and all the tricks with electronics, tramblings and other things are crushing. Let's get closer to this node, consider the Ignition Candle and Nuances, which you need to know for novice drivers.

So, as we already know with you, the heroine of this article is needed in order to ignite the fuel and air mixture in the motor cylinder.

Unfortunately, very often the owners of the machines do not pay due attention to these elements, considering them simple consumable material. In fact, the candles, like many other engine nodes, require a certain proportion of attention, because they depends the stability of the operation of the power unit.

In addition, sufficiently high demands are presented to their reliability. Only imagine under what conditions you have to work with candles - high voltage fed to their electrodes (up to 40,000 volts), high temperatures reaching 1000 degrees and aggressive chemical processesassociated with combustion of fuel. All this dictates certain conditions that the ignition candle can be answered, and on this further ...

Despite all the responsibility lying on the shoulders of the candles, their design is quite simple. As stated: "The simpler, the more reliable." It consists of such parts:

• contact rod (tip);
• central electrode;
• ceramics insulator;
• metal case;
• resistor;
• side electrode.

The contact rod or, as it is also called, the tip is designed to connect with high-voltage wires of the ignition system.

Another end of the rod through a resistor, which serves to reduce the level of interference from the spark discharge, is connected to the central electrode, and all these elements are placed in an insulator from refractory ceramics.

The insulator, as follows from its name, is used to prevent short circuit between the central electrode, which is supplied to a voltage to 40,000 volts and the case having a reliable electrical connection with the "mass". The insulator has not only the outer part, which is visible, but also the inner (the so-called heat cone), which goes straight into the combustion chamber of the motor cylinder.

With the right mode of operation of the power unit and the candle, the heat cone performs a very important role - on its surfaces, due to the high temperature, the particles of soot are burned, self-cleaning of the candle from the products of combustion of fuel and the deposits do not accumulate.

But if suddenly the temperature of the thermal cone exceeds the permissible, then the variety of mixture can occur - an extremely negative phenomenon in which fuel is flammable not from the spark, but from heated to very high temperatures of the insulator.

Metal case combines the above internal details and has a thread for screwing into the landing place.

Well, the last element is the side electrode. It is welded to the body and is located near the central electrode. It is between them and skipping a spark, an animating gasoline engine.

What do you need to know the car owner?

Car owner is useful to know not only the ignition candle device, but also its main characteristics. Only so you can pick up the optimal model of this part, which is best for the motor. There are several of them:

• a calil number is a very important parameter, it depends on it whether the vanish ignition will occur in the cylinders, which can lead to serious breakdowns Engine. Each motor in the specification indicates the recommended value of this parameter and it is extremely desirable to use the corresponding candles - not with great and certainly not with a smaller number;
• spark gap - in fact, this is the distance between the central and side electrode. The smaller it is necessary to form a spark;
• the ability to self-cleaning is how the candle copes with fuel combustion products and sediments. Any objective scale does not have this parameter - it is necessary to believe in the word manufacturers;
• the working temperature of the candle - should be located within 500 - 900 degrees Celsius;
• the diameter of the candle and the length of the thread - the first parameter is usually 14 mm, and the second depends on the power of the motor - the more horses under the hood, the longer there should be a thread, as a rule, from 12 to 25 mm.

Many of these characteristics manufacturers indicate the candles housing in the form of special ciphers, to solve that can be solved using tables.

There are also interchangeability tables - a model of which candle without problems can be replaced with another.

As we can see, friends, the heroine of today's article - the element is not easy and for the motorist, it is important to know not only the spark plug device, but also its parameters, in order to replace the problems with force aggregatewhich can turn in expensive repair.

At this, the story about the candle comes to an end, and I will start preparing the following articles in which I will tell you about other secrets hiding in the depths of cars.

To start the engine operation, it is necessary to ignite the mixture in the cylinders. To do this, the ignition candle is used, between the electrodes of which the spark arises, the flammable mixture in from the candle state largely depends on the normal start and engine performance.

Any spark plug has a steel case. At its lower part there is a thread for turning the candle and its side electrode into part of the chamber. Inside the body of the candle, in a sealed insulator there is a metal rod, it serves as a central electrode. On its top there is a thread for summing up the armor tip. The base of the candle is a ceramic insulator.

For proper and durable operation, the lower part of the insulator with the engine running should reach a temperature of up to 600 0 C. Under these conditions, the oil is full of combustion, which falls on the electrodes, and does not form a nagar. With such temperature mode Self-cleaning of the candle is ensured.

If the temperature is lower, the oil does not completely burn, and in the electrodes, the insulator and the body of the candle are formed a curly crust. The result of this is the failure of its work, the disappearance of the spark feed (the discharge can not break through the sediment layer). In such cases, a cylinder ignition occurs, that is, the fuel mixture is ignited not from the electrospray, but from the interaction and direct contact with the chopped parts of the candle.

The design features of the central electrode and the insulator are made of candles to the cold (with the highest heat transfer) and hot (with low heat transfer). The ability to scap the heat characterizes the calil number of spark plug. It is indicated on the candle and means time (in seconds), after which the calillery will occur.

Each convoy, caring for his car, knows the spark plugs on pollution and deposits. With a well-running engine, correctly and ignition, with proper work The candles themselves can be seen on them the deposits of light brown.

The appearance of a light gray or whitish plaque on the insulator cone speaks of the presence of such problems as small fuels, overheating with candles due to the wrong poor composition of the working mixture.

Dry black loose Nagar testifies to re-enrichment of the mixture, late ignition, quite frequent engine work in the engine. If you adjust the ignition system, the NAAR will disappear.

Oil black flare is a sign of a cold candle. The spark does not appear on it, or there is no compression in the cylinder, and it does not give the power, with the result that the engine works unevenly.

Red-brown deposits on the insulator cone are the result of fuel combustion, which contains many additives. Such an ignition candle is subject to a replacement or mechanical cleaning.

We can safely say that the ignition candle is not working, if: its carving in oil, the body rim is covered with a friable black nagar, dark brown spots on electrodes and insulator, chip and burnout on the insulator cone. Ground candles in the engine with huge mileage talk about wear pistons, cylinders, rings.

Reduce and exclude various troubles will help qualified auto maintenance, every 15-20 thousand km, and timely troubleshooting.

Spark candles are used. Arson with a combustible mixture is made by electric discharge voltage of several thousand or tens of thousands of volts arising between the electrodes of the candle. The candle works on each cycle at a certain point in the engine operation.

IN rocket engines The candle lights the fuel mixture with an electrical discharge only at the time of launch. Most often, in the process of operation, the candle is destroyed and unsuitable for reuse.

In turbojet engines, the candle flames the mixture at the time of running a powerful arc discharge. After that, the burning of the torch is supported independently.

Kalil and at the same time catalytic candles are used in model engines internal combustion. The fuel mixture of the engines specifically contains components that are easily flammable at the beginning of work from a split candle wire. In the future, the races of the thread is supported by the catalytic oxidation of the vapor of alcohol included in the mixture.

Device of spark plugs

The ignition candle consists of a metal housing, an insulator and a central conductor.

Spark plug details

Contact pin

The contact output located in the top of the candle is designed to connect the candle to high-voltage wires of the ignition system or directly to the individual high-voltage ignition coil. There may be somewhat slightly different design options. Most often, the wire to the ignition candle has a snatching contact, which is put on the output of the candle. In other types of design, the wire can be attached to the candle with a nut. Often, the conclusion of the candle is made universal: in the form of an axis with a thread and a screwing snap-in contact.

Ribra Isolator

The radomb of the insulator prevent electrical breakdown along its surface.

Insulator

The insulator is usually made from aluminum-oxide ceramics, which should withstand temperatures from 450 to 1000 ° C and voltage up to 60,000 V. The exact composition of the insulator and its length partially determine the thermal marking of the candle.

A portion of the insulator directly adjusted to the central electrode, the most strongly affects the quality of the ignition candle. The use of a ceramic insulator in a candle is proposed by G. Honold due to the transition to high-voltage ignition.

Seals

Serve to prevent the penetration of hot gases from the combustion chamber.

Base (housing)

It serves to wrap the candle and hold it in the thread of the cylinder head, to remove heat from the insulator and electrodes, and also serves as a conductor of electricity from the "mass" of the car to the side electrode.

Side electrode

As a rule, made from nickel doped and manganese steel. Welded with contact welding to the case. The side electrode is often very heated while working, which can lead to a callery ignition. Some candle designs use several side electrodes. To increase the durability, the electrodes of expensive candle are supplied with platinum attacks and other noble metals. Since 1999, a new generation candles have appeared on the market - the so-called plasma-forkar candles, where the body of the candle is played by the role of the side electrode. At the same time, a ring (coaxial) spark gap is formed, where the spark charge moves in a circle. This design provides a large resource and self-cleaning of the electrodes. The shape of the side electrode in the breakdown area resembles the nozzle of Laval, due to which the stream of cracks, expiring from the inner cavity of the candle. This flow effectively ignites the working mixture in the COP (combustion chamber), completeness of combustion and power increases, the toxicity of DVS decreases. The effectiveness of the "Forkarm" candle is questioned by the ecperimet.

Central electrode

The central electrode is usually connected to the contact terminal of the candle through a ceramic resistor, it allows you to reduce radio interference from the ignition system. The tip of the central electrode is made of iron-nickel alloys with the addition of copper, chromium and noble and rare earth metals. Usually the central electrode is the most hot candle item. In addition, the central electrode must have a good ability to emissions of electrons, to facilitate spark formation (it is assumed that the spark is planned in the phase of the voltage pulse when the central electrode serves as a cathode). Since the tension of the electric field is maximum near the edge of the electrode, the spark skips between the sharp edge of the central electrode and the edge of the side electrode. As a result of this edge of the electrodes, the largest electric erosion is subjected. Previously, the candles were periodically removed and removed traces of erosion emery. Now, thanks to the use of alloys with rare-earth and noble metals (yttrium, iridium, platinum, tungsten, palladium), the need for sweeping electrodes almost disappeared. The service life at the same time increased significantly.

Gap

The gap is the minimum distance between the central and side electrode. The magnitude of the gap is a compromise between the "power" spark, that is, the dimensions of the plasma arising from the test of the air gap and between the ability to break through this gap in a compressed air-gasoline mixture.

The factors determined by the gap:

1. The greater the gap - the greater the size of the spark, \u003d\u003e more likely to ignite the mixture and more ignition zone. All this positively affects fuel consumption, uniformity of work, reduces the quality of fuel, increases power. Too increasing the clearance, too, it is impossible, otherwise the high voltage will look for more light paths - punch the high-voltage wires on the body, punch the candle insulator, etc.
2. The more the gap - the harder it is to pierce it spark. The insulation breakdown is called the loss of insulation of insulation properties when the voltage is exceeded by a certain critical value called the punching voltage U PR. Appropriate electric field strength E PR \u003d U PR / Hwhere h. - The distance between the electrodes is called the electrical strength of the gap. That is, the more gap - the greater the breakdown voltage U PR necessary. There is another dependence on the ionization of molecules, the uniformity of the structure of the substance, the polarity of the spark, the rate of increasing the impulse, but this is not important in this case. It is clear that the high voltage U PR cannot change - it is determined by the ignition coil. But we can change the g of H.
3. The field strength in the gap is determined by the form of electrodes. What they are sharper - the more the intensity of the field in the gap and lighter to the breakdown (like iridium and platinum candles with the subtle C. E.).
4. The gap penetration depends on the gas density in the gap. In our case, from the density of the air-gasoline mixture.

What it is more - the harder it is to pierce. The punching voltage of the gas gap with a homogeneous (OP) and weakly inhomogeneous (SNP) electric field depends on both the distance between the electrodes and the pressure and temperature of the gas. This dependence is determined by the Law of Pashen, according to which the punching voltage of the gas gap from the OD and the SNP is determined by the product of the relative density of the gas δ by the distance between the electrodes S, U PRF (ΔS). The relative gas density is called the ratio of the gas density in these conditions for the gas density under normal conditions (20 ° C, 760 mm Hg. Art.). Clear clearance is not a constant once specified. It can and must adapt to a specific engine operation situation.

Modes of operation of candles

Spark candles of gasoline engines according to the mode of operation are conventionally divided into hot, cold, medium. The essence of this classification is to the degree of heating of the insulator and electrodes. When working, the insulator and electrodes of any candle should be heated to temperatures contributing to the "self-cleaning" of their surface from combustion products fuel mixes - Nagara, soot, etc. Therefore, the insulators of candles operating in optimal mode are always the colors of "coffee with milk".

Cleaning the surface of insulators is necessary to prevent surface leaks high voltage Through a nagar layer, which reduces the power of the spark breakdown of the gap, or in general makes it impossible. However, if the elements of the candle are heated too much, the uncontrolled calilie can occur. The process is often manifested by large turns. This can lead to detonation and destruction of engine elements.

The degree of heating of the elements of the candles depends on the following main factors:

• Internal
  • construction of electrodes and insulator (long electrode heats up faster)
  • material of electrodes and insulator
  • material thickness
  • the degree of thermal contact of the elements of the candle with the case
  • the presence of a copper core CE
• External
  • degree of compression and compression
  • fuel type (more high-octane has a greater combustion temperature)
  • ride style (on large speed and engine loads Heating candles larger)

Hot Candles - The design of the candles is specifically designed in such a way that heat transfer is reduced from the central electrode and the insulator. Used in low compression engines and when using low-fuel. Since in these cases less temperature in the combustion chamber.

Cold candles - the design of the candles is specifically designed in such a way that the heat transfer from the central electrode and the insulator as much as possible. Used in high-compression engines, with high compression and using high-octane fuel. Since in these cases there are more temperatures in the combustion chamber.

Medium candles - occupy an intermediate position between hot and cold (the most common)

Optimal candles - the design of the candles is designed in such a way that heat transfer from the central electrode and the insulator is optimal for this particular motor.

Unified candles - the calil number captures the range of cold and hot candles. It is thanks to the "half-openness" candles, the problems of ventilation and clogging by the products of incomplete combustion are not terrible.

Candles are normally self-cleaning in all modes of engine operation and at the same time do not lead to a callery ignition.

Typical sizes of spark plugs

The dimensions of the spark plug are classified by the type of thread on them. The following thread types are used:

• M10 × 1 (motorcycles, such as candles of type "T" - TU 23; chainsaws, lawn mowers);
• M12 × 1.25 (motorcycles);
• M14 × 1.25 (cars, all candles like "A");
• M18 × 1.5 (Candles of the M8 brand, installed on the "old" car engines GAZ-51, GAZ-69; "Tractor" candles; Candles for gas pipeline DVS et al.)

The second classification feature is thread Length:

• short - 12 mm. (ZIL, GAZ, PAZ, UAZ, Volga, Zaporozhets, Motorcycles);
• long - 19 mm. (VAZ, AZLK, IZH, Moskvich, Gazelle, almost all foreign cars);
• extended - 25 mm. (modern forced DVS);
• candles with shorter threads can be installed on small-sized engines (less than 12 mm)

Turnkey head size (hexagon):

• 24 mm (Candles of the brand "M8" with a thread M18 × 1.5)
• 22 mm (Candles of the brand A10, engine engines ZIS-150, ZIL-164)
• normal - 21 mm (traditional, for DVS with two valves per cylinder);
• average - 18 mm (for ICA some motorcycles)
• reduced - 16 mm or 14 mm (modern, for internal circulation with three or four valves per cylinder);

Kalil number (thermal characteristic):

• Hot candles 11-14;
• Medium candles 17-19;
• Cold candles 20 or more;
• Unified candles 11-20.

Thread sealing method:

• With flat gasket (with ring)
• With conical sealing (without ring)

The number and view of the side electrodes:

• Single-electrode - traditional;
• Multielectrode - several side electrodes;
• Special, more resistant electrodes for gas or for larger run;
• Tormetic - unified ignition candles, there is a cone resonator for symmetric fuel mixture.
• Plasma-forcar - side electrode is made in the form of a nozzle of the boiler. In conjunction with the body of the candle, the internal forkamar forms. The ignition occurs at the forecastern way.

see also

Links

	Spark plug on wikisklad