Comprehensive maintenance of screw air compressor methods and procedures

　　That's so complete! Screw air compressor cleaning and maintenance methods and processes, in practical applications, the working conditions of air compressors are often more complex, dust, oil and various particles. The air compressor has been used for a long time, there will be oil scale, carbon deposits, sediment, rust, etc. inside, if you have used air compressors of different brands of lubricating oil, there will be black glue similar to asphalt. Therefore, it is necessary to clean regularly, clean the machine head, paint bucket, radiator, oil pipe, and various valves, etc., to achieve the purpose of eliminating potential safety hazards.
　　
　　First, the whole machine cleaning
　　
　　Air pressure cleaning method: first run the air compressor for a few minutes, and the oil reaches normal temperature; Turn off the air compressor, wait for the internal pressure to be discharged, open the oil filling cap, pour in the air compressor cleaning agent, and tighten the oil filling cap; Turn on the air compressor and run for 30 minutes; Drain the old oil and add the new oil. Generally, the temperature of the air compressor after cleaning will drop by about 10 degrees.
　　
　　Second, cooler cleaning, in China, the cooler of the air compressor is generally divided into two types: air-cooled and water-cooled, so there are different cleaning methods for different coolers.
　　
　　2.1 Air-cooled cooler, open the wind shroud to clean the cover, or remove the cooling fan; Use compressed air blowback to blow the dirt down, and then take the dirt out of the wind shroud; If it is dirty, you should spray some degreaser and blow again. When the screw air compressor cannot be cleaned by the above methods, the cooler needs to be removed, soaked or sprayed with cleaning liquid and cleaned with the help of brushes (it is strictly forbidden to use wire brushes). Install the cover or cooling fan.
　　
　　2.2 Water-cooled cooler, disassemble the cooling water inlet and outlet pipes. Inject the cleaning solution to soak or circulate with a pump (the backflush effect is better). Rinse with clean water. Install the cooling water inlet and outlet pipes. When the oil cooler is seriously fouled and the above methods are not ideal for cleaning, the oil cooler can be removed separately, the end covers at both ends can be opened, and the scale can be removed with a special cleaning steel brush or other tools. When cleaning the medium side of the cooler cannot effectively reduce the temperature, the screw air compressor needs to clean the oil side, the method is as follows: disassemble the inlet and outlet pipes; Inject the cleaning solution to soak or circulate with a pump (the backflush effect is better); Rinse with clean water; Blow dry with dry air or remove water with dehydrating oil; Install the inlet and outlet pipes.
　　
　　Third, clean the water and gas separator, screw air compressor water and gas separator structure is similar to oil and gas tank, the air inlet is designed against the wall, solid into centrifugal force, due to the weight factor of water and gas, so it can effectively separate the moisture in the compressed air. Cleaning of the water and gas separator: The cover of the water and gas separator can be disassembled and cleaned with a detergent.
　　
　　4. Load reducing valve (intake valve) cleaning, load reducing valve is composed of valve body, valve core (piston), air path manifold, solenoid valve and proportional valve (capacity regulating valve) and other components. The load reduction valve mainly controls the loading (screw air compressor heavy truck), unloading (empty vehicle), proportional (capacity adjustment) control of the air compressor, in addition, it can prevent the lubricating oil from spraying from the main engine when the air compressor is stopped.
　　
　　Load reducing valve disassembly: (1) Remove the hose connected by the load reducing valve and the air filter; (2) Remove the gas pipe connected to the load reduction valve by all other components; (3) Remove the solenoid valve coil; (4) Remove the nut assembled between the load reduction valve and the main engine and remove it; (5) Move the load reduction valve to the ground covered with clean paper or related clean laying.
　　
　　Cleaning load reducing valve: (screw air compressor cleaning agent should use soap water, diesel, clean gasoline, tianna water, etc., should be selected according to the degree of dirt The above cleaning agent, generally recommended to use soap water or diesel fuel for cleaning).
　　
　　Remove the solenoid valve: Remove the solenoid valve and check whether the O-ring and sealing piece in the solenoid valve need to be replaced (reminder: if you are not familiar with the intake valve, please also note the location of the removed component to avoid errors when replacing it). If there is no need to replace the disassembled screws, O-rings, sealing sheets, electromagnetic rods, cores and other components, put them in the container prepared in advance, and soak them in appropriate cleaning agents (Note: When choosing gasoline and Tianna water as cleaning agents, please do not soak rubber products such as O-rings for too long to avoid corrosion).
　　
　　Remove the proportional valve: remove the proportional valve from the valve body, and then unscrew out the adjusting nut (it is best to make a mark on the nut before screwing, so as not to replace it when the proportional value deviation is too large), take out the valve core, O-ring, U-ring, spring and check whether the O, U-ring needs to be replaced (all seals and springs removed by the screw air compressor must be checked, and will not be repeated in the following description), and put the removed elements into the cleaning agent to soak.
　　
　　Removal of the manifold block: remove the manifold block from the valve body, there are air holes on the four sides of the manifold (the hole of the screw air compressor is to dredge when the integrated air path is blocked), unscrew the sealing nut on the air hole and put the manifold together into the cleaning agent to soak.
　　
　　Remove the load reduction valve core: use the circlip pliers to remove the circlip located at the connection between the valve core and the valve body, and then use the pipe pliers to unscrew out the valve core, take out the cylinder, valve plate, O-ring, U-ring, spring and put it into the cleaning agent to soak, and then remove the air inlet on the valve body, put the entire valve body into the soak, at this time, the disassembly process of the load reducing valve has been completed.
　　
　　Cleaning: If the dirt of the intake valve is more serious, then change a new cleaning agent when cleaning, the cleaning process should first wash the cleaner parts and then wash the dirty parts, the cleaned parts should be washed again with clean water, so as to avoid corrosion and shorten the service life of the components, the parts washed with clean water should be put in a clean place to dry, so as to avoid rust of iron-containing parts.
　　
　　When cleaning the valve plate and the place where the valve body is in contact with the valve plate, attention should be paid to the flatness of the surface, and it should be cleaned and replaced if necessary, otherwise it will cause the air compressor to start with load (the screw air compressor large unit will produce the phenomenon of unable to start when starting with load).
　　
　　Installation of components: component installation is carried out according to the reverse step of disassembly, it should be proposed that when installing components, the position of the sealing ring and the active components should be coated with an appropriate amount of oil, which can make the sealing ring better installed and the moving parts more flexible.
　　
　　Due to the large number of parts of the load reducing valve, if you are not sure to remember the position of each part, you can clean each part and then install the part, but the parts should not be installed on the valve body first, and then assembled into the valve body after all the parts are cleaned. After the whole cleaning process of the load reducing valve is completed, it is put aside and ready to be loaded into the air compressor.
　　
　　Fifth, the minimum pressure valve (pressure maintenance valve) cleaning, in the screw air compressor although the minimum pressure valve looks relatively small, but don't look at it small, it controls the whole machine. In order to make it work normally under normal work, the following provides the maintenance method of the minimum pressure valve of the screw air compressor.
　　
　　The minimum pressure valve is composed of the minimum pressure valve body, valve core, adjusting nut, spring, sealing element, etc. The minimum pressure valve mainly plays the role of establishing the internal pressure of the unit, promoting the circulation of lubricating oil, and meeting the working pressure of the load reduction valve, in addition, the minimum pressure valve also plays the role of a one-way valve to prevent the compressed air in the air tank from flowing back to the air compressor when the unit is unloaded.
　　
　　The structure of the minimum pressure valve is very simple, unscrew the nut of the screw air compressor between the valve core and the valve body to take out the components inside, the minimum pressure valve core of the small unit is built into the valve body, and all the internal components can be taken out by disassembling the valve body cover. The minimum pressure valve can clean the minimum pressure valve according to the method of cleaning the load reducing valve. Since the structure of the minimum pressure valve is very simple, the assembly process will not be described one by one, but it should be noted that if there is a U-ring inside, it is necessary to pay attention to the direction of the U-ring. The screw air compressor minimum pressure valve is put aside after the whole cleaning process is completed, and it is ready to be loaded into the air compressor. 　　6. Oil return check valve cleaning
　　
　　The check valve is composed of valve body, steel ball, steel ball seat, spring and other components. The oil-gas mixture compressed by the main engine of the air compressor is first separated by centrifugal force in the oil and gas tank, because the weight of the oil is greater than the air, most of the oil in the solid oil-gas mixture falls to the oil tank through centrifugal force, and the screw air compressor then returns to the main engine under the action of internal pressure for a lubrication cycle process, and the compressed air containing a small amount of oil is separated again by the oil and gas separator, at this time the lubricating oil separated by the oil and gas separator will fall to the bottom of the oil and gas separator, in order not to let this part of the oil take away with the compressed air, The unit is designed with an oil pipe inserted into the bottom of the oil and gas separator, through the action of internal pressure, this part of the oil is directly introduced to the main engine for lubrication, and there is a check valve on the oil pipe, and the screw air compressor is called the oil return single valve.
　　
　　Its function is to smoothly recover the oil of the oil and gas separator to the main engine without allowing the oil of the main engine to flow back to the oil and gas separator. The oil return single valve has a connection in the valve body, unscrew from there, and take out the spring, steel ball, and steel ball seat. Clean the oil return check valve: clean the valve body, spring, steel ball, steel ball seat with cleaning agent, and some check valves also have a filter screen inside, if there is any, clean together.
　　
　　7. Screw air compressor cleaning temperature control valve
　　
　　The temperature control valve is composed of valve body, valve core, temperature sensing element, spring, etc. Temperature control valve plays a constant temperature control role, when the temperature control valve temperature sensing element measured oil temperature is lower than the action value (temperature sensing element action value is generally 71 degrees), the lubricating oil directly from the oil and gas barrel back to the host, when the temperature control valve temperature element measured oil temperature is higher than the action value, temperature control valve temperature sensing element ejector action, push the valve core to open its own equipped bypass valve, so that the lubricating oil into the cooler cooling (if the temperature measured by the temperature sensing element is higher, the greater the bypass valve open), the cooled lubricating oil back to the host.
　　
　　There is a cover on the surface of the temperature control valve of the screw air compressor, there is a screw hole on the cover, find a suitable nut to screw the cover, and then use the circlip pliers to take out the circlip that fixes the cover, and then use the pliers to pull the nut just screwed in, you can remove the cover and all the internal parts. Clean all parts of the temperature control valve according to the method of cleaning the load reducing valve. After all the above parts are cleaned and dried, they are installed in the air compressor, and all components should be checked again for omissions and clean up the tools and other items used during installation.
　　
　　8. Correct all parameters
　　
　　After the machine is cleaned and installed, the operating parameters of the air compressor should be adjusted to ensure the normal and safe operation of social security:
　　
　　(1) Preparation before the screw air compressor starts: belt (coupling) correction: if the air compressor is driven by a belt, the tightness of the belt should be between 10~20 mm. If the air compressor is a coupling drive, after installation, the motor and the main engine should be moved by hand and the balance of the coupling should be checked. Screw air compressor couplings basically adopt elastic couplings, which can be ignored when the solid balance deviation is not large. Screw air compressor host steering correction: if the main power supply has been removed during maintenance, the power supply should pay attention to the forward and reverse rotation of the motor after it is connected, the steering of the motor should be according to the steering of the host, the correct steering of the host Please check the steering icon marked on the host. Correction method: exchange any two power lines in the three-phase electricity.
　　
　　(2) Loading, unloading, proportional value efficiency: when setting the three parameters, the unloading value should be determined first, the unloading value should be determined according to the rated pressure of the air compressor and the pressure required by the air end, and then set the loading value after determining the unloading value. The pressure difference between the two should be between 0.1 ~ 0.2MPa, after setting the unloading and loading values, the final set proportional value, the proportional value should be set in the middle of the unloading value and the loading value, screw air compressor example: if a factory needs the air supply pressure of the air compressor 0.8MPa, and the air supply requirements are relatively stable, three parameters should be set as follows: unloading pressure setting 0.8MPa, loading pressure setting 0.65MPa, proportional control pressure setting between 0.73~0.75MPa. Screw air compressor correction method: set this parameter in the microcomputer controller (if the control of the air compressor adopts button control, the loading and unloading parameters should be adjusted from the pressure switch, and the proportional value should be adjusted at the adjusting nut of the proportional valve on the load reduction valve).
　　
　　(3) The internal pressure of the unit is positive: the internal pressure of the unit should be between 0.2~0.45MPa. Correction method: the pressure value should be carried out when the unit is unloaded, the size of the value is adjusted on the adjusting nut of the minimum pressure valve, in order to facilitate the reading of the adjusted value, the pressure detection point should be taken before the minimum pressure valve and installed a pressure gauge (some microcomputer controllers have internal pressure parameter display function, if there is no function, the pressure gauge should be installed before the minimum pressure valve).
　　
　　(4) High temperature protection value is positive: when the screw air compressor works normally, its temperature should be between 65~98 °C. The automatic shutdown temperature of the protection shall not exceed 105°C. Correction method: adjust the high temperature automatic shutdown temperature value in the controller, preferably 1.2 (that is, amplify the 20% margin).
　　
　　Summary, the correct maintenance and maintenance plays a vital role in the service life and operational reliability of the screw air compressor, and air compressor cleaning is a skill that after-sales maintenance service personnel and even equipment operators must master. For more information about Zhigao screw air compressor, pay attention to the official website of our Hunan Ruisheng Electromechanical Equipment - www.hnzega.com。