Function description and maintenance method of each component on the main air source channel

1. Air filter

The air filter is a dry paper filter, and the pore size of the filter paper is about 5 μm. Its main function is to filter out dust in the air and avoid premature wear of the screw rotor and premature blockage of the oil filter and fine oil separator. Usually every 500 hours of operation, the dust on its surface should be removed. The method of removal is to use low-pressure air to blow the dust from the inside out.

Maintenance method of air filter:

The air filter is best maintained once a week. Unscrew the gland nut, take out the air filter element, compress the air with 0.2-0.4Mpa, blow out the dust particles on the outer surface of the air filter element from the inner cavity of the air filter element, use a clean cloth to clean the air filter Wipe off the dirt on the inner wall of the shell, and reinstall the air filter element, paying attention to the tight fit between the sealing ring at the front end of the air filter element and the inner end face of the air filter shell. The heavy duty air filter can be opened directly to the housing, and the maintenance method is the same as above.

Under normal circumstances, the air filter should be replaced every 1500-2000 hours. In places where the environment is particularly harsh, such as mines, ceramic factories, cotton spinning factories, etc., it is recommended to replace the air filter element every 500 hours. Please use genuine filters when replacing.

When cleaning or replacing the air filter, the parts must be matched one by one to prevent foreign objects from falling into the intake valve.

Usually, it is necessary to check whether the intake telescopic pipe is damaged or flattened, and whether the connection between the telescopic pipe and the air filter intake valve is loose or leaking. If found, it must be repaired and replaced in time.

2. Intake valve

The intake valve is a disc-type intake valve, which mainly controls the empty and heavy load through the opening and closing of the disc in the intake valve; there are two control methods, one is switch type, when the pressure reaches the high limit set value , close the air inlet, the pressure drops to the lower limit set value, and reopen the air inlet to work at full load. Another kind of capacity adjustment control, the disc of the intake valve is slightly closed with the proportional valve for capacity adjustment control, adapting to the external air consumption, so that the pressure is stabilized within a certain range, and the pressure does not reach the capacity adjustment pressure, the disc of the intake valve is fully open, the compressor is running at full load.

Maintenance method of intake valve:

The failure of the air valve is generally that the screw machine is not unloaded and the intake valve is not closed. Without loading, the intake valve solenoid valve is damaged. The screw machine is injected with oil, and the valve body control block is faulty. The screw machine is overloaded, and the intake valve is opened in advance when starting. Therefore, the intake control valve should be replaced with maintenance kits regularly to maintain a good working condition. During each maintenance, the parts must be removed, and the wear of each friction surface should be checked. In particular, the surface of the rubber sealing ring should be checked. If it is damaged or cracked, new parts must be replaced. After cleaning, the friction surface of metal parts should be coated with lubricating oil.

3. Oil and gas barrels

The oil and gas barrel has two functions of oil and gas separation and oil storage. The compressed oil and gas mixture is discharged to the oil and gas barrel, and most of the lubricating oil can be separated by rotating in the oil and gas barrel; there is more lubricating oil in the oil and gas barrel, so that the hot oil that has just been separated will not immediately participate in the next cycle, which is conducive to reducing the discharge of oil. air temperature. There is an oil level indicator on the side of the oil and gas drum. There is a refueling hole on the barrel for refueling, and the oil level of the static lubricating oil should be between the upper and lower limits of the oil level gauge. The oil (water) ball valve is installed under the oil and gas barrel. The ball valve should be slightly opened before each operation to remove the condensed water in the oil and gas barrel (because water is heavier than oil, it is deposited in the lower part). As soon as oil comes out, shut it off quickly. Due to the wide cross-sectional area of ​​the oil and gas barrel, the flow rate of the compressed air can be reduced, which is conducive to the separation of oil droplets and plays the role of preliminary oil removal.

4. Safety valve

When the gas pressure in the oil and gas barrel is 1.1 times higher than the rated exhaust pressure, the safety valve will automatically jump up and release the pressure, so that the pressure drops below the rated exhaust pressure. The way to check the safety valve is to lightly pull the relief lever on the safety valve when the compressor is working at full load. If the safety valve can exhaust air, it is considered normal.

Maintenance method of safety valve:

In order to ensure that the performance of the air compressor safety valve does not change, the air compressor safety valve must be maintained and cleaned regularly to prevent ash, water vapor, stains, etc. from entering the valve body and affecting the performance of the valve body.

monthly maintenance items

The air compressor safety valve needs to be maintained every month, and the maintenance personnel must be professional personnel, otherwise it will cause problems with the valve body during the maintenance process. The monthly maintenance contents include cleaning the oil filter and oil-gas separator, and the air filter also needs to be cleaned. There are also cooling equipment that needs to be lubricated, as well as checking all parts of the pump body to eliminate potential safety hazards, and cleaning the valve body.

Annual maintenance items

The annual maintenance item is the most important maintenance in the air compressor safety valve, which is different from the monthly, in which the inspection is more extensive. Regarding the annual maintenance items, it is necessary to clean the oil circuit and the water vapor circuit for stains, etc., and adjust the various parts of the valve body to check whether there is any problem. If there is any problem, it needs to be replaced in time.

5. Minimum pressure valve

Located at the outlet of the fine oil separator above the oil and gas poke, the opening pressure is set to about 0.45MPa. The minimum pressure valve mainly has the following functions:

When starting, the circulating pressure required by the lubricating oil is preferentially established to ensure the lubrication of the machine.

After the gas pressure of the oil and gas barrel exceeds 0.4MPa, it will be opened, which can reduce the air flow rate flowing through the oil fine separator, not only ensure the oil fine separation effect, but also protect the oil fine separator from being damaged due to too large pressure difference.

Return function: When the pressure in the oil and gas tank drops after shutdown, it prevents the backflow of compressed air in the pipeline.

The maintenance method of the minimum pressure valve:

Check the valve cover temperature on a regular basis, record the surface temperature of the outer cover of the minimum pressure valve and make an icon record. Combined with the instrument to detect the operating parameters of the equipment (such as temperature and pressure), according to the recorded temperature changes, analyze the operating status of the minimum pressure valve and predict its life. Reasonable arrangement of maintenance time.

The operating sound of the minimum pressure valve is detected by using the auscultation rod and other tools to monitor the movement sound of the minimum pressure valve valve plate and compare it with the valve of the same level and the same name.

Analyzing changes in process parameters Once the minimum pressure valve leaks, it will cause changes in temperature, pressure or flow. Through the changes of these parameters, it can be analyzed which stage of the minimum pressure valve or even which minimum pressure valve is faulty.

6. After cooler

Compressed air from the minimum pressure valve goes to the aftercooler. The after-cooler and the oil cooler are made into one body, and their structure is the same, both of which are plate-up type. A cooling fan draws in cool air and blows it over the rear cooler rocker. The temperature of the compressed air after cooling is generally below the ambient temperature +15°C.

Maintenance method of aftercooler:

The cooler should be cleaned regularly according to the environmental conditions, so that the compressor can work at a normal temperature to ensure a long service life of the machine. When the cooler is dirty and blocked, the exhaust temperature of the compressor will increase. Generally, the outside of the air-cooled cooler should be cleaned every 1500 hours, and the water side of the water-cooled cooler should be cleaned every 1500 hours. Regular cleaning of the cooler has the following benefits:

It is good for the performance and life of the machine to make the unit always work under the ideal working temperature (below 95 ℃).

The dirt can be removed by using cleaning fluid, otherwise, when the dirt is thick, the cleaning work is quite troublesome, and the cooler needs to be disassembled, and the cleaning work can be completed by means of mechanical methods.



Function description of the main components of the second oil circuit

1. Thermostatic valve

The main function of the temperature control valve is to control the exhaust temperature of the compressor by controlling the humidity of the lubricating oil injected into the machine head, so as to prevent the water vapor in the air from condensing in the oil and gas barrel to emulsify the lubricating oil. When the machine is just turned on, the temperature of the lubricating oil is low, the temperature control valve is closed, and the cold oil is directly sprayed into the body without passing through the cooler. If the oil temperature rises above 70°C, the temperature control valve will gradually open the passage to the oil cooler, and fully open when it reaches 76°C. At this time, all the oil will be cooled by the oil cooler and then injected into the body. Some machines The model does not have a temperature control valve, but controls the oil temperature by controlling the stop of the fan motor. When the exhaust temperature rises to 85°C, the fan starts to run; when the exhaust temperature is lower than 75°C, the fan automatically stops to keep the temperature within a certain range.

Maintenance method of temperature control valve

Disassembly of the temperature control valve: There is a cover on the surface of the temperature control valve of the screw air compressor, and there are screw holes on the cover. Find a suitable nut and screw it into the cover, and then use the circlip pliers to take out the circlip that fixes the cover. Then use the pliers to pull the nut that was screwed in just now to take off the cover and all the internal parts.

Cleaning the temperature control valve: The cleaning agent should be soapy water, diesel oil, clean gasoline, Tianna water, etc. The above cleaning agents should be selected according to the degree of dirt. Generally, soapy water or diesel oil is recommended for cleaning. If the dirt of the temperature control valve is serious, replace it with a new cleaning agent when cleaning.

2. Oil cooler

The oil cooler is integrated with the aftercooler.

3. Oil filter

The oil filter is a paper filter with a filtration accuracy between 10μ and 15μ. Its function is to remove impurities from the oil. Such as metal particles, dust, oil deterioration, etc., to protect the normal operation of bearings and rotors. If the oil filter is blocked, it may cause insufficient fuel injection, affect the service life of the main engine bearing, and increase the exhaust temperature of the machine head (or even shut down).

How to maintain the oil filter

Every 100h or within a week of the drilling rig work: the primary filter screen of the oil filter and the coarse filter screen on the fuel tank must be cleaned. When cleaning, remove the filter element and use a wire brush to brush off the dirt on the net. Working in a dusty environment, frequent cleaning of the air filter and oil filter is essential, neglecting this will cause a series of failures.

Every 300h: Clean the filter core, blow dry after cleaning, and then soak the same oil in the oil tank. If the dust is very serious, determine the cleaning cycle according to the actual situation. When you can see the red line of the air pollution indicator on the unloading valve, it means that the air filter is seriously polluted and the air filter should be cleaned. Clean or inspect parts such as unloading valves, minimum pressure valves and automatic venting valves. Thoroughly clean the oil filter to remove the dirt deposited on the bottom of the oil filter.

Every 1000h: The oil filter paper filter element must be replaced. Check whether the safety valve, temperature control valve, pressure regulator and pressure regulating valve work normally.

Every 3000h: Check the oil pump, check or replace the sealing ring. According to the emulsification degree of the base oil, the amount of impurities, and the change of viscosity, replace the new oil as appropriate. Oil separator filter element parts, generally can be used 2000 ~ 4000h. No special maintenance is required during this time. If it is found that the oil consumption of the compressor increases significantly, check or replace the core, unscrew the two M24×1.5 bolts on the exhaust seat, check the clearance of the exhaust valve, and adjust as appropriate. When used in a dusty environment, the dust is easy to accumulate on the oil cooler, and the cooling effect is deteriorated. It should be cleaned according to the specific situation. Generally, it is required to clean it once every 4 months to ensure the heat dissipation effect.

4. Oil fine separator

The filter element of the fine oil separator is made of multi-layer fine special fibers. The mist lubricating oil contained in the compressed air can be almost completely filtered out after passing through the fine oil separator. The oil particle size can be controlled below 0.1μm, and the oil content is Can be less than 3PPM.

Maintenance method of oil fine separator

Oil and gas separators generally have blockage failures. If you find that the oil and gas filter is clogged, it may be caused by the following reasons:

Check the environment around the press. Whether there is corrosive gas, for example, in some occasions, there will be sulfide, water, cleaning chemicals, etc., volatilized in the air. Or whether the air compressor temperature is too high.

Use qualified air filter, oil filter and oil. Timely change the oil, filter, etc.

Check for leaks in the line between the air filter and the air inlet of the main unit. Common causes of leakage are: the air filter is not installed properly; the contact area of ​​the air filter assembly is uneven; the contact surface between the air filter and the assembly has dirt attached to it, causing leakage; the elastic contact pad on the air filter surface is placed crooked ; Air filter or air filter assembly rupture, etc.

Check whether there is too much water on the oil filter material to prevent the oil resistance from increasing and blocking in advance.

5. Oil return check valve

The residual oil filtered by the fine oil separator is concentrated in the small circular groove in the center of the filter element, and is led to the main engine through the oil return pipe to prevent the separated lubricating oil from being discharged with the air. In order to prevent the backflow of oil in the compression chamber of the main engine, a one-way valve is installed after the oil return pipe. If the oil consumption suddenly increases during the operation of the machine, check whether the throttle orifice of the one-way valve is blocked.

Maintenance method of oil return check valve:

Dismantling of oil return single valve: There is a connection in the valve body, unscrew from there, and take out the spring, steel ball and steel ball seat.

Cleaning the oil return check valve: Use cleaning agent to clean the valve body, spring, steel ball, steel ball seat, and some check valves have a filter screen inside, if there is, clean them together.

Three gas circuit control parts

1. Load solenoid valve

Normally closed solenoid valve for two positions. Through the power-on and power-off of the solenoid valve, the on and off states of the gas circuit are controlled, and the loading and unloading functions are realized.

2. Vent valve

When unloading or shutting down, the valve is opened to release the pressure in the oil and gas tank, so that the compressor can run at a low load, or ensure that it can be restarted under no-load conditions.

3. Inverse proportional valve

Exceeding the set adjustment pressure will only work. At this time, the higher the proportional valve (that is, the exhaust pressure of the system), the lower the output control pressure. The lower the control pressure, the smaller the opening of the air intake unloading valve disc controlled by the cylinder expansion and contraction, and the smaller the intake air volume of the compressor, so that the air supply volume of the compressor and the air consumption can be kept in balance. Stepless air volume adjustment function. The way to set the regulating pressure is to lift the black cap of the inverse proportional valve upwards and turn it, turn it clockwise to increase the pressure, and turn it counterclockwise to decrease it. Once set, depress the cap to prevent it from spinning on its own due to vibration. The set value should generally be less than the rated exhaust pressure. If it is higher than the unloading pressure set by the microcomputer controller, there will be only empty trucks and no capacity adjustment.

4. Sensors

Pressure and temperature sensors can measure various parameters to realize screw air compressor loading, unloading, various fault prompts, and automatic shutdown when necessary.