Pass multiple test runs. Finding the above-mentioned appearance of the fault: Only when the car is continuously driving, the automatic transmission will lock the gear and enter the protection mode. At this time, if the engine is turned off for a few seconds and the car is driven again, the automatic transmission will return to normal operation. According to the analysis of the failure law, the temperature of the engine and the automatic transmission changes with the travel time, which is likely to be a stable display of a control or a working element of the automatic transmission. Check intake manifold, no leakage; check throttle control mechanism, no problem; check idle motor, normal. Then read the engine dynamic data flow, and found that there are four items of data is not normal, these four data are: injection pulse width is 7.30ms at idle (normal value is 2.6ms), the signal pressure of the intake manifold absolute pressure sensor is 3.3V (normal value should be 1.sv), the idle motor step number is 102 (normal value is 30), ignition advance angle is l to 20, and unstable. Comprehensive analysis of the above four items of data, the focus of conflict is concentrated on the intake manifold absolute pressure sensor, its signal voltage is too high, making the injection pulse width increases. At this point, the oxygen sensor detected a rich mixture.

The engine electronic control unit then instructs the idling stepper motor to increase the intake air volume, thereby causing an increase in the number of idling steps, and the engine electronic control unit also continuously adjusts the mixture to check that the intake manifold is not leaking. Further inspections found that the engine is powerful and has good power. This means that there will be no problem with mismatched valve timing and blocked exhaust pipes. Vacuum is applied to the intake manifold absolute pressure sensor by the vacuum gun. The sensor indicates that the sensor is normal. Based on the above inspection results, it is concluded that the fault location may be in the EGR system. After dismantling inspection, it was found that the EGR solenoid valve was stuck in the open position, the exhaust back pressure tube was broken, and the exhaust back pressure valve base was severely cracked. Replace EGR solenoid valve troubleshooting. According to past experience, the first thought was the automatic transmission control unit, and some of its electronic components were suspected to have become abnormal at high temperatures. Then they put on a normal running vehicle with the same type of automatic transmission control unit, and the failure still failed. exclude.

Bright Steel Bar


BRIGHT STEEL BAR


Bright steel bar is carbon or alloy steel bar with shining bright surface which is improved by cold drawing, peeling, turning, grinding and polishing over hot rolled black surface bars. By cold drawing, the steel bar yield strength and tensile strength will be improved. By peeling and turning, the surface imperfections will be removed. By grinding, the diameter tolerance will be more precision. By polishing, the surface will be much more shining.

peeled steel bar processing

Except the shining bright surface, comparing with the hot rolled black surface bars, the bright steel bars has better surface roughness, better roundness, straightness, more precision size tolerance etc.

Heat treatment such as annealing, normalizing, quenching and tempering will be done before do cold finishing on the hot rolled bar to get bright steel bar, in such condition, the steel bright bar will get most suitable mechanical properties to meet different application requirement.

The advantages of steel bright bars we supply:

1) Big stocks of hot rolled round bars or wire rods as raw materials

2) Heat treating furnaces to adjust the mechanical properties

3) Full sets of testing equipment to test the sizes, mechanical properties and microstructure.

4) Multiple packages to avoid broken packages and anti-rusty

Diameter tolerance

+0/-0.02mm

Straightness

0.5mm/m

Surface roughness

0.4um

Roundness

80% of diameter tolerance

Diameter range

14mm to 100mm

Steel grade

Kinds of carbon steel and alloy steel

Length

Any length can be cut with precision tolerance


Bright Steel Bar,Bright Steel Round Bar,Steel Bright Bar,Bright Polished Steel Bar,Alloy Steel Bright Bar Manufacturer

SHANDONG LE REN SPECIAL STEEL CO., LTD. , https://www.sdthreadedrods.com