Forklift vacuum booster system fault analysis and

Web Design And Seo For www.china-webdesign.com

fork attachment - China Manufacturer

Thank you for inquiry my fork attachment, Tel：13989310707, E-mail: sales@steelmanattachment.com

http://www.forklift-fork.com/key-fork-attachments-194/

(1) vacuum turbocharger failure of the vacuum booster system booster.
The reason is as follows. 60 - II-type vacuum booster from the pressure cylinder (secondary tank), the control

room, vacuum plus strength room ( power cylinder) constitute the Control valve within the diaphragm was

separated into left and right cavity. The vacuum valve and air valve is one, rely on the spring action.

Forklift braking, the vacuum valve and the diaphragm seat center hole between the normal open state, the air

valve to maintain the state of NC. The power cylinder before the film is divided into, after the cavity before

the cavity with the vacuum tank connected to the vacuum tank through the tube and is connected to a vacuum

pump; after cavity connected to the right chamber of the tube and control valve.
When the engine is started but have not depress the brake pedal, the vacuum booster power cylinder ago, after

the chamber and control valve of the left and right chamber connected to each other, have the same degree of

vacuum, so the role of the return spring, the power cylinder The film with the center push rod in the backward

limit position.
When the engine is started, the brake pedal,excavator parts
brake oil enter the turbocharger wh en the master cylinder

hydraulic rise to a certain value, all the way through the auxiliary cylinder piston center hole flow to the

front left and right brake wheel cylinders; all the way to promote control shifted to the right of the valve

piston, diaphragm seat to close the vacuum valve, so that the control valve left and right cavity isolation

(equivalent to the power cylinder, spleen separated from the child) and opens the air valve, power cylinder

chamber filled with air, and the former cavity remains a certain degree of vacuum. Therefore, after the cavity

to produce the pressure difference force power cylinder film to drive the push rod to move forward, putting

the top ball off dead center hole of the auxiliary piston, thereby promoting the piston moves forward, the

master cylinder to the oil pressure (booster), brake wheel cylinders, and thus obtain a higher oil pressure,

so the whole car to get a good braking performance.
We can see from the above works, the power cylinder vacuum determines the level of the forklift braking system

with vacuum booster of boost the role of good or bad. The decline was due to the power cylinder vacuum: vacuum

pumps, vacuum valves and air valves, poor performance or power cylinder coating damage, which the vacuum

valve, poor sealing of the air valve is the most common. Vacuum valve is not sealed, the vacuum valve is

closed when the pedal is pressed, the first chamber of the power cylinder,forklift accessories
but the air still seepage from

between the vacuum valve and valve seat caused the decline of the power cylinder vacuum, so that the putter

thrust greatly decreases, the auxiliary tank can not form a high pressure, thereby reducing the braking

performance of the entire vehicle.
Similarly, if the air valve leak, the brake pedal power cylinder cavity had been penetrated air pedal power

cylinder vacuum will be greatly reduced. Therefore, the control valve, vacuum valve, air valve is the vacuum

supercharger supercharger is less than the most common point of failure. From our many years of maintenance

practice, the vacuum pump oil is a lethal factor caused by the vacuum turbocharger damage. Will cause the

valve due to the vacuum system into the oil, coating damage, if there is pumping oil phenomenon is necessary

to promptly repair or replace the vacuum pump. In addition, poor pump performance, connecting pipe breakage

leakage and Park, Kuang Yung bucket cloth Hironari straight, the pressure of the turbocharger.
(2) vacuum booster system failure, the following shall be the method to judge and exclude
â'  check of vacuum pump
a manual inspection: Remove the vacuum pump pipe joints, finger blocked vacuum pipe interface, start the

en gine, if the finger is sucked, the vacuum pump is good; if the suction is weak, then the vacuum pump

failure, required to repair. b vacuum gauge test: the vacuum gauge connected to the vacuum tube, start the

engine, regardless of the engine at any speed, the vacuum degree of not less than 500mm mercury column,

otherwise the repair or replacement of the vacuum pump.
â'¡ vacuum booster check
a. listen to check first, start the engine a few minutes after the flame, depress the brake pedal several

times, each could hear the vacuum booster emitted by the \"hiss, hiss\" sound, if loud, but with with the

stampede increase in the number gradually diminished, then basically we can conclude that the good performance

of vacuum turbocharger.
Start the engine, a brake pedal and hold the control valve, vacuum valve and air valve closed, the brake is in

equilibrium (with a wisp of c otton yarn on the air filter of the vacuum booster mouth should be no

inhalation); another person after power cylinder chamber air tube removed, and quickly fingers to block the

air nozzle and cavity fittings, nozzle suction vacuum valve does not seal, should overhaul or replacement;

joint suction, then the power cylinder coating is damaged, to be replaced.
start the engine, not the brake pedal, a wisp of cotton yarn on the control valve, air filter mouth, such as

cotton yarn is sucked indicates that the air valve leakage, and to dismantling the control valve, the

replacement of the apron or the air valve.