Excavator brake pneumatic system, in between the pump and the reservoir pump equipped with a gas control valve, its main function is to separate compressed air Petroleum and water, filtered compressed air in the red dust and impurities, preventing gas storage bins compressed air back to the pump to ensure the gas pressure stabilized at 0.490-0.637MPa within the framework of a maximum pressure of not more than 0.784MPa. Failures often occur with the use of the following:
Pressure regulating valve damage due to leakage wither laminated sheet
Regulator diaphragm 6 as rubber, to withstand pressure due to its frequent repeated stamping, repeated hog, reset action, subject to gas, water corrosion, so Guchang diaphragm is damaged, it is most likely to occur in the control valve failure. Damaged diaphragm from the pump to the compressed gas through the membrane into the upper relief valve, rather than into the gas storage bins, causing reservoir pump pressure rise can not get on. At this point easy to increase the temperature relief valve, brake system pressure gauge showed less than atmospheric pressure, pressure regulating valve Office may hear the sound leakage.
Control valve shell rupture
The valve housing from the upper, middle and lower three parts, respectively, with screw connection. As the shell is made from aluminum, in the decomposition or a combination, if the demolition, installation screws improper methods, easy to make the shell burst. Down on the demolition, installation screws, they shall sub-diagonal and multiple loose screw or a screw, so that the surface of the shell by combined force to maintain its population in line, and prevent damage to both Shouli Bu.
Filter damaged
Compressed air filter is mainly used to filter out the dust and impurities, to prevent such substances into the excavator's braking system. It consists of filter 30, vacuum pad 32 and a fixed drain plug 33 composed of, if prolonged use, maintenance not timely, it easy to filter wire breakage, vacuum pad damage. Therefore, caution should be maintained in the maintenance, if the damage shall promptly repair or change.
Pressure Regulating Valve to adjust air pressure is too high or too low
Normal working hours, if the gas storage barrel reached 0.637MPa gas pressure, the pressure regulating valve that is the lower pressure relief, so that pressure will not increase gas storage barrel. When the gas storage cylinder with air pressure below 0.49MPa, then should not be a pressure relief. The adjustment of this pressure can be changed by adjusting the screw a large spring 19 of the clamping force (tightening the gas increases; screw loose, pressure reduction) to achieve, such as the air pressure is still not adjusted properly, you can have two situations: a is the atmospheric pressure has been exceeded but failed to exhaust pressure relief. At this point you should consider whether to run the exhaust piston 12 o'clock blocked, and as a result of the piston cylindrical tight O-ring 34, the lower part of the exhaust piston spring 10 excellent, leaving the normal pressure of gas can not push the piston to run, they should wear uniform cut or adjust the outer ring, replacement springs. If the relief valve spring 18 compressed within the small tight, thimble 8 is difficult to promote, plug 9 axial hole blockage, can make air pressure can not be unloading; second is not yet reached the required pressure to exhaust pressure relief when it started. First, pressure regulator diaphragm leaks this reason, the second is due to the small pressure regulating valve spring too loose (or broken), or under pressure in the lower thimble can be promoted, so that relief valve on the shell holes continue to leak gas, causing the system pressure does not rise up. In this case the valve should first remove one screw on the first adjustment or replacement of a small spring, and then adjust the big spring.
The adjustment of the pressure relief valve is not normal
The role of safety valve is to ensure that gas storage cylinder with air pressure of not more than 0.78MPa. If the pressure exceeds 0.78MPa when the pressure relief valve still will make gas storage cylinder with air pressure continue to rise. This may be safety valve diaphragm 25 leak, valve spring 16 excellent result; such as air pressure does not meet the requested relief, because the weak spring is poor, inadequate preload, the valve 26 and valve seat 27 is not sealed making. You should adjust or replace the damaged parts, respectively.
Gas cylinder with gas shutdown after the back
Storage bins in order to prevent backflow of gas after the shutdown, the control valves are equipped with one-way valve 29, if the shutdown of gas after the gas storage bins back to the pump, this failure were due more to a one-way valve spring 28 elastic is too weak or broken lose role, should be adjusted or replaced this spring.
Excavator working pressure maintained at 0.490-0.637MPa within the maximum pressure shall not exceed 0.784MPa, an exception occurs when the pressure should be adjusted to the pressure regulating valve and safety valve. Making mechanical adjustments, adjust the safety valve should be an order of the first adjustment as follows:
1,screw on the pressure regulating valve to adjust the fixed nut screw loose, and then adjust the screw screwed in the end, so that the lower part of the exhaust valve can not be opened.
2, observe the safety valve when the pressure 0.784MPa can exhaust from the exhaust vent. If pressure does not increase or decrease to adjust to normal through the pads 23 be adjusted; low air pressure, increase gaskets, whereas reduction of gaskets, gaskets for each additional 1mm adjustable pressure 0.036MPa.
3,the relief valve adjusting screw out slowly until the exhaust valve opens to exhaust date, if the pressure at this time just for 0.637MPa was the best.
4,continuous excavators under the brake pedal repeatedly rub or to put gas pump reservoir at this time should be observed pick-up in pressure (exhaust piston off) is in between the 0.490-0.539MPa, if the pick-up in pressure is less than 0.490MPa, while the upper row of holes exhaust the same time, this time should be adjusted to a small spring pressure.
5, repeated adjustments, testing, until the compliance date.
Pressure regulating valve damage due to leakage wither laminated sheet
Regulator diaphragm 6 as rubber, to withstand pressure due to its frequent repeated stamping, repeated hog, reset action, subject to gas, water corrosion, so Guchang diaphragm is damaged, it is most likely to occur in the control valve failure. Damaged diaphragm from the pump to the compressed gas through the membrane into the upper relief valve, rather than into the gas storage bins, causing reservoir pump pressure rise can not get on. At this point easy to increase the temperature relief valve, brake system pressure gauge showed less than atmospheric pressure, pressure regulating valve Office may hear the sound leakage.
Control valve shell rupture
The valve housing from the upper, middle and lower three parts, respectively, with screw connection. As the shell is made from aluminum, in the decomposition or a combination, if the demolition, installation screws improper methods, easy to make the shell burst. Down on the demolition, installation screws, they shall sub-diagonal and multiple loose screw or a screw, so that the surface of the shell by combined force to maintain its population in line, and prevent damage to both Shouli Bu.
Filter damaged
Compressed air filter is mainly used to filter out the dust and impurities, to prevent such substances into the excavator's braking system. It consists of filter 30, vacuum pad 32 and a fixed drain plug 33 composed of, if prolonged use, maintenance not timely, it easy to filter wire breakage, vacuum pad damage. Therefore, caution should be maintained in the maintenance, if the damage shall promptly repair or change.
Pressure Regulating Valve to adjust air pressure is too high or too low
Normal working hours, if the gas storage barrel reached 0.637MPa gas pressure, the pressure regulating valve that is the lower pressure relief, so that pressure will not increase gas storage barrel. When the gas storage cylinder with air pressure below 0.49MPa, then should not be a pressure relief. The adjustment of this pressure can be changed by adjusting the screw a large spring 19 of the clamping force (tightening the gas increases; screw loose, pressure reduction) to achieve, such as the air pressure is still not adjusted properly, you can have two situations: a is the atmospheric pressure has been exceeded but failed to exhaust pressure relief. At this point you should consider whether to run the exhaust piston 12 o'clock blocked, and as a result of the piston cylindrical tight O-ring 34, the lower part of the exhaust piston spring 10 excellent, leaving the normal pressure of gas can not push the piston to run, they should wear uniform cut or adjust the outer ring, replacement springs. If the relief valve spring 18 compressed within the small tight, thimble 8 is difficult to promote, plug 9 axial hole blockage, can make air pressure can not be unloading; second is not yet reached the required pressure to exhaust pressure relief when it started. First, pressure regulator diaphragm leaks this reason, the second is due to the small pressure regulating valve spring too loose (or broken), or under pressure in the lower thimble can be promoted, so that relief valve on the shell holes continue to leak gas, causing the system pressure does not rise up. In this case the valve should first remove one screw on the first adjustment or replacement of a small spring, and then adjust the big spring.
The adjustment of the pressure relief valve is not normal
The role of safety valve is to ensure that gas storage cylinder with air pressure of not more than 0.78MPa. If the pressure exceeds 0.78MPa when the pressure relief valve still will make gas storage cylinder with air pressure continue to rise. This may be safety valve diaphragm 25 leak, valve spring 16 excellent result; such as air pressure does not meet the requested relief, because the weak spring is poor, inadequate preload, the valve 26 and valve seat 27 is not sealed making. You should adjust or replace the damaged parts, respectively.
Gas cylinder with gas shutdown after the back
Storage bins in order to prevent backflow of gas after the shutdown, the control valves are equipped with one-way valve 29, if the shutdown of gas after the gas storage bins back to the pump, this failure were due more to a one-way valve spring 28 elastic is too weak or broken lose role, should be adjusted or replaced this spring.
Excavator working pressure maintained at 0.490-0.637MPa within the maximum pressure shall not exceed 0.784MPa, an exception occurs when the pressure should be adjusted to the pressure regulating valve and safety valve. Making mechanical adjustments, adjust the safety valve should be an order of the first adjustment as follows:
1,screw on the pressure regulating valve to adjust the fixed nut screw loose, and then adjust the screw screwed in the end, so that the lower part of the exhaust valve can not be opened.
2, observe the safety valve when the pressure 0.784MPa can exhaust from the exhaust vent. If pressure does not increase or decrease to adjust to normal through the pads 23 be adjusted; low air pressure, increase gaskets, whereas reduction of gaskets, gaskets for each additional 1mm adjustable pressure 0.036MPa.
3,the relief valve adjusting screw out slowly until the exhaust valve opens to exhaust date, if the pressure at this time just for 0.637MPa was the best.
4,continuous excavators under the brake pedal repeatedly rub or to put gas pump reservoir at this time should be observed pick-up in pressure (exhaust piston off) is in between the 0.490-0.539MPa, if the pick-up in pressure is less than 0.490MPa, while the upper row of holes exhaust the same time, this time should be adjusted to a small spring pressure.
5, repeated adjustments, testing, until the compliance date.
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