2.14.7. Spark plugs
The spark plug consists of the insulator, the case, the central electrode and an electrode of weight. The electrode of weight is densely fixed in the insulator. The insulator is rigidly connected to the case. Between central and an electrode of weight the ignition spark which ignites air-fuel mix slips.
Ease of start, the characteristic of idling, acceleration and speed limit depend on a spark plug. Proceeding from it it is impossible without the bases to deviate from type of the candles ordered by manufacturer which is defined by kalilny number. The Kalilny number specifies degree of thermal loading of a candle in the engine in certain service conditions.
Candles for the engine are selected so that they in various service conditions reached self-cleaning temperature. The kalilny number of a spark plug, the higher it resistance to kalilny ignition and the less its resistance to pollution is lower. The kalilny number of a candle, the less its resistance to kalilny ignition and the higher it resistance to pollution is higher.
The Kalilny number of a candle contains in a spark plug code. The code is deciphered as shown below.
BOSH spark plug
Example:
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F
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R
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G
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D
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U
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R
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1
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2
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3
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4
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5
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6
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F – a carving of M14x1,25 with flat landing, SW16;
M – a carving 18 x 1,5 with flat landing, SW25;
N – a carving of M14 x 1,25 with conical landing, SW16;
D – a carving of M18 x 1,25 with conical landing, SW 21;
SW – the key size.
2. R – with the noise suppressing resistor. Work of system of ignition at the same time is not broken.
3. Kalilny number. The Kalilny scale has designations from 06 ("cold") up to 13 ("more hotly"). At the same time number 7 corresponds to old kalilny number 175 (old designation), 6-200, 5-225, etc.
4. And – length of a carving is 12,7 mm, a normal trajectory of the spark category;
In – length of a carving of 12,7 mm, the extended trajectory of the spark category;
With – length of a carving is 19 mm, a normal trajectory of the spark category;
D – length of a carving of 19 mm, the extended trajectory of the spark category;
DT – length of a carving of 19 mm, the extended trajectory of the spark category, the 3rd electrode of weight;
L – length of a carving of 19 mm, strongly extended trajectory of the spark category.
5. Electrode material of the central electrode: Cr-Ni alloy;
With – the central electrode from the Ni connection - the SI;
S – silver central electrode;
Р – platinum central electrode;
About – a standard spark plug with the strengthened central electrode.
6. R = 1 kOhm, resistance to an obgoraniye, X – distance between electrodes of 1,1 mm.
Thanks to impregnations of copper (SI) in the central electrode and, even more, when using a silver electrode heat conductivity and consequently, thermal loading increases. Advantage of a spark plug with a platinum central electrode is high ability to sparking, small wear and wide kalilny range.
BERU spark plug
Example:
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14
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F
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G
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D
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U
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R
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1
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2
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3
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4
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5
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6
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2. A design, for example To – for conical landing, F – for flat landing, SW16, R with the noise suppressing register.
3. Kalilny number. The Kalilny scale has designations from 06 ("cold") up to 13 ("more hotly"). At the same time number 7 corresponds to old kalilny number 175 (old designation), 6-200, 5-225, etc.
4. And – length of a carving is 12,7 mm, a normal trajectory of the spark category;
In – carving length 12,7mm, the extended trajectory of the spark category;
With – length of a carving is 19 mm, a normal trajectory of the spark category;
D – length of a carving of 19 mm, the extended trajectory of the spark category;
FROM – length of a carving of 19 mm, the extended trajectory of the spark category, the 3rd electrode of weight;
L – length of a carving of 19 mm, strongly extended trajectory of the spark category.
5. Electrode material, for example, with U copper impregnations.
6. R = 1 kOhm, resistance to an obgoraniye.