In the long process of piston skirt, prone to severe wear, damage and fracture, local surface strain, prone to severe wear ring groove plane.
(1) the phenomenon and causes of serious wear and tear of the piston
When Baotou beiben heavy truck parts piston serious wear, cylinder seal will deteriorate, cylinder pressure decreased obviously, and the lubricating oil may also enter the combustion chamber, resulting in increased oil consumption, fault phenomena of blue smoke exhaust. Under the action of lateral force, the piston will also appear in the motion of the cylinder knocking phenomenon. Serious wear and tear of the piston is generally due to the piston and the cylinder sleeve between the inner wall lubrication is not caused by the deterioration of the installation position of the piston.
(2) the burning or fault phenomenon and reason
Fault or fracture of the piston burning generally occurs in the piston combustion chamber throat and valve pit edge and corner parts, as well as regional precombustion chamber nozzle flame shock. Piston fracture generally occurs at the top of the piston and piston pin seat hole. When the piston has high thermal stress and impact load, the piston will be burning or cracking phenomenon in these parts. After the piston fracture, diesel engine speed will be significantly decreased, the crankcase ventilation hole will emit a lot of smoke.
The main reason there is damage and fracture of the piston:
Diesel engine is often in the state of overload, the top of the piston thermal load and gas thrust is too large.
Diesel engine in the running of the coolant temperature is too high or too little coolant, resulting in diesel engine combustion chamber components overheating.
The clearance between the piston and the cylinder wall is too small, when the piston is at work after the expansion of the heated cylinder and the piston pull off, stuck.
The valve into the cylinder and cylinder caused by accident.
The Baotou beiben heavy truck parts of the cylinder oil injection pump was uneven, caused by the individual cylinder supply is too large, resulting in heat load exceeds the limit temperature allowed by the piston material.
(3) the phenomenon and reason of piston abrasion failure
The abrasion surface will appear after the axial grooves of different, this failure is usually due to the oil too dirty or assembly parts cleaning not clean caused.
Failure and cause of plane wear of (4) piston ring groove
The piston in the use of the most serious wear position of the piston ring groove plane, this is because the impact of high pressure gas cylinder, piston ring unit pressure on the piston ring groove is very high, at the same time in the reciprocating movement of the piston, piston ring in the ring groove of the piston is also a great impact, and high working temperature. In the piston ring, the top gas pressure piston ring a the maximum, bearing temperature is the highest, so the top ring groove is a most serious wear, several other ring groove wear are reduced from top to bottom. Ring groove wear is mainly in the ring groove, and the upper plane wear less. Ring slot after long-term use, the channel will become trapezoidal cross-section, the outer width of the narrow, so that the side gap increases, resulting in cylinder sealing performance decline, serious, but also make the cylinder oil leakage and leakage phenomenon.
The serious wear, loss or fracture after repair method
Baotou beiben heavy truck repair parts of the piston when the piston is difficult, serious wear, damage or fracture, should be replaced with a new piston of the same type.