Chapter 7 Each System Separate No-load Test Run and Its Conditions
After the complete equipment is fully installed, each system must be tested separately with sufficient preparations to find hidden dangers in the installation timely and accurately, and to check and adjust the internal structural relationships and parameter relationships. After confirming that the system is in the normal state, the next procedure can be entered.
1. Main drive system and motor no-load test run and its conditions
⑴ Clean the reducer with kerosene. Pour the appropriate amount of kerosene into the box of the reducer and soak it first. When the main motor can drive, it will rotate without load and clean the tooth surface;
⑵Connect the main motor and cooling fan power supply, and confirm that the main motor is running normally without load, install and tighten the flange connecting bolts of the main motor and the universal joint drive shaft;
(3) Unscrew the two screw plugs on the lower side of the reducer case, release kerosene for cleaning, and then tighten the screw plugs. Pay attention to whether the sealing ring is intact. If it is damaged, replace it in time. When using substitutes, ensure that the sealing ring material is oil-resistant rubber sheet.
⑷Pour in the used lubricating oil, and pay attention to ensure that it reaches the position indicated by the oil mark.
2. Selection of lubricants
Reducer should choose different lubricating oil according to different environment, different temperature or season.
⑴Use in normal ambient temperature, that is, the temperature is above -15℃ in winter and below 38℃ in summer. N220 sulfur-phosphorus type medium and extreme pressure gear oil can be selected in the north; N320 sulfur-phosphorus type medium and extreme pressure gear oil can be selected in the south. If the manufacturer chooses other types of lubricating oil according to the situation of the factory, it should be negotiated with the equipment manufacturer or research unit;
⑵If the working environment temperature is higher than 40℃ and lower than 60℃, N460 sulfur-phosphorus type medium extreme pressure gear oil should be selected;
⑶ When the working environment temperature is lower than -15℃, all oil products should be negotiated with the research and development unit.
3. Replace Oil
Different types of oils cannot be mixed. If you need to change the oil type, you should drain the oil in the reducer first, and clean the reducer before injecting new lubricating oil.
4. Necessary conditions for no-load test run of the driving system:
(1) The steering of the main motor wiring is correct, and the anchor bolts have been tightened;
(2) The connecting flange bolts of the universal joint drive shaft and the bolts of the universal joint bearing seat and the base plate have been tightened as required;
(3) The hand plate of the planetary reducer operates flexibly and has been lubricated;
(4) The shrink sleeve coupling has been installed and the shrink bolts have been tightened as required;
(5) The butterfly spring in the torque support has been adjusted and preloaded, the connecting rod mechanism installation meets the requirements, and the joint bearing has been filled with lubricant. (2﹟ or 3﹟ molybdenum disulfide base grease can be used);
(6) Check and confirm that there is no foreign matter that hinders the rotation of the driving system and the rotation of the grinding roller. Especially there is no iron block and other debris in the nip;
(7) The roller press is in the non-feeding state.
5. No-load test run of the system
(1) Listen carefully to whether the running sound of the main bearing is normal;
(2) Listen carefully to see if the sound of the planetary reducer is normal;
(3) Observe whether the shaking of the universal joint drive shaft during operation is within the allowable range;
(4) Listen carefully to whether the running sound of the main motor is normal; check whether the direction of the cooling fan is correct;
(5) Observe whether the no-load current of the motor is within the normal range;
(6) No-load test operation should be guaranteed for more than 4 hours continuously, and the temperature rise, running sound and motor current of each part and the working condition of the control cabinet should be observed frequently during the operation.
2. Hydraulic system test run
1. Charge the accumulator
(1) The inflation must be nitrogen, oxygen and air are strictly prohibited, otherwise there is the danger of explosion;
(2) Connect the inflation tool to the nitrogen bottle. Remove the safety cover and valve cap of the accumulator charging valve. Screw the other end of the inflation tool to the accumulator. Check whether the air release valve of the accumulator is tightened;
(3) First, open the valve of the accumulator, check the residual pressure in the accumulator, close its valve, and open the valve of the nitrogen cylinder to check the pressure in the nitrogen cylinder;
(4) Keep the valve of the nitrogen bottle open, slowly unscrew the accumulator inflation valve, so that the bladder slowly expands. Pay attention to the pressure gauge on the charging tool, and often close the valve of the nitrogen cylinder to check whether the accumulator has reached the predetermined charging pressure.
(5) The actual charging pressure of the accumulator should be greater than the pre-charging pressure by about 5kg/c㎡. After the charging is completed, stay for about two minutes. When the gas in the accumulator is stable and the temperature returns to normal, slowly open the discharge of the accumulator. The gas valve adjusts the pressure in the accumulator to the predetermined inflation pressure;
(6) Close the charging valve of the accumulator and the valve of the nitrogen bottle, remove the charging tool at the end of the accumulator, and check with soapy water to confirm that the charging valve of the accumulator does not leak before tightening the bonnet and safety cover.
2. Preparation of hydraulic oil
(1) The hydraulic system must be clean, all valves and pipes have been installed, without any exposed nozzles and cavities;
(2) Check the quality of the hydraulic oil to be used, and directly observe its viscosity, color, cleanliness and transparency. To prevent mistakes, it must be strictly filtered before filling the hydraulic oil tank.
3. Selection of hydraulic oil
In order to keep the hydraulic system in good working condition and stable working performance, prevent the hydraulic equipment from rusting and excessive wear, so as to ensure the service life of the whole equipment and improve the operation rate. The specified hydraulic oil must be used. It is not allowed to use ordinary machine oil.
⑴ In most areas of North China, East China and South China, when the ambient temperature is higher than -20℃ and lower than 40℃, HL series hydraulic oil can be used in the north. Generally choose N32, and the South chooses N46;
⑵In Northeast, Northwest and other regions, the ambient temperature is lower than -10℃ and higher than -30℃, and low-condensing hydraulic oil N32 or N46 can be used.
⑶ If the user needs to change the type of hydraulic oil in order to make the factory oil storage management convenient, please contact the research unit for confirmation.
⑷Once a certain hydraulic oil has been selected and used, it is generally not suitable to change the oil, and only need to check regularly and replenish the hydraulic oil.
4. Preparation before hydraulic system test run
⑴Check whether all pipe joints and flanges are connected in place;
⑵Check whether all the directional valves are consistent with the required direction of action;
(3) Adjust all the relief valves to the minimum pressure;
⑷Open the exhaust valve of the hydraulic system;
⑸ Check whether the oil level of the hydraulic oil in the hydraulic oil tank is within the specified height;
⑹ Use the switch on the side of the machine to jog the hydraulic oil pump to observe whether the steering is correct;
⑺Check whether there is any debris that hinders its operation when the moving roller shaft system moves horizontally, and whether it may interfere with other equipment, especially whether there are foreign objects or iron blocks between the two grinding rollers and the four bearing seats that hinder the movement of the moving roller;
⑻The connecting parts of the main frame are installed in place, and the connecting bolt groups have been evenly tightened according to the specified tightening torque;
5.The setting relationship of the pressure control valve and pressure gauge parameters in the hydraulic system (refer to the hydraulic system drawing).
Set: ⑴The upper limit pressure of the electric contact pressure gauge is PD;
⑵The lower limit pressure of the electric contact pressure gauge is PD;
⑶The charging pressure of the accumulator is Px;
⑷The set pressure of the electromagnetic liquid flow valve is Pv1;
⑸The setting pressure of the overflow valve of the pumping station is Pv2;
⑹The set pressure of the pressure sensor is PcY;
⑺ The setting pressure of the relief valve in the low pressure chamber is Pv3;
Then: ⑴PD up-PD down=1.2～2.0Mpa;
⑵ PD under -Px≥0.6～1.5Mpa;
Setting basis: On the electric contact pressure gauge, the smaller the lower limit pressure difference, the better the consistency of the physical properties of the extruded material. However, the hydraulic system has pressure fluctuations when it is working, so the difference is generally set at three times the fluctuation pressure.
The closer the charging pressure of the accumulator is to the lower limit of the electric contact pressure gauge, the shorter the time for the system to pressurize. But their difference should not be less than 1.5 to 2 times of the fluctuating pressure, and the inflation pressure should not be less than 60% of the upper limit pressure of the electric contact pressure gauge, otherwise the bladder in the accumulator is easily damaged.
From the setting relationship of the above parameters, it can be seen that the size relationship of PY1, PY2, and PCY is PCY>PV1>PV2, which also reflects the system's triple protection measures: 1. When the system pressure exceeds the set pressure PV2 of the overflow valve of the pumping station, the pressure is relieved through the overflow valve to protect the system; 2. If the overflow valve of the pumping station fails, the electromagnetic overflow valve is used to relieve the pressure of the system, which also plays a protective role; 3. If the above two overflow valves fail, the system pressure is transmitted to the control system through the pressure sensor, and the control system implements interlocking shutdown.
It can be seen from the schematic diagram that the maximum pressure of the system is 16.0Mpa, and the working pressure depends on the specific conditions, generally 7-9Mpa.
7. Hydraulic system commissioning
The hydraulic system can be divided into the following three circuits: pressurization circuit, roll back circuit, pressure protection circuit, during the test run, the following steps can be carried out:
⑴ Debug the pressure of the pump station, check the working performance of the gear pump and oil pump motor
① Adjust the handle of the pump station relief valve (part 6) to the most loose state;
②The three-position four-way reversing valve (part 7) is in the power-off state;
③Start the oil pump motor;
④ After confirming that the motor and the oil pump are running normally and balanced, slowly tighten the relief valve handle, and use 1Mpa as the step-up speed to gradually increase the oil pump pressure to 10Mpa. During this period, pay attention to whether its adjustment is flexible.
Note: During the debugging process, if oil is leaking from the gear pump seal ring, you can consider whether the oil pump motor is reversed.
⑵Using the roller inlet oil circuit to exhaust the system
① Inflate the accumulator according to the set inflation pressure;
② Adjust the components to the state where the moving roller is pushed forward;
③Start the oil pump motor and fill the system with oil and exhaust at the set pressure. Pay attention to whether there is oil coming out of the exhaust valve on both sides (or at the pressure gauge switch installation place). If there is no oil on both sides or only one side, you should continue to fill the system with oil until the oil comes out. Tighten the exhaust valve (or install the pressure gauge) after the gas in the system is exhausted.
Note: When only one side is emitting oil, the exhaust valve on that side can be tightened and closed, and then the system can be filled with oil.
⑶ Debug each oil circuit, check the reliability and sensitivity of each component of the system.
Set the system pressure to P
1. Debugging the oil circuit of roller inlet
a. Adjust the charging pressure of the accumulator to (0.65～0.85)P;
b. Set the upper and lower limit pressure of the electric contact pressure gauge to:
Upper limit PD=(P＋0.70)Mpa;
Lower limit PD lower=(P-0.70)Mpa;
c. Adjust the directional valves to the left roll state;
d.Start the oil pump motor and adjust the pressure of the pump station relief valve to (P+0.5)Mpa (can be read from the pump station pressure gauge);
e. Adjust the handle of the electromagnetic overflow valve in the combination valve so that the electric contact pressure gauge shows the same pressure as the pressure gauge of the pump station, and on this basis, slightly tighten the electromagnetic overflow valve handle;
f. Observe whether the left roller is advancing flexibly. Because it is the single-side roller, the advancing distance should not be too long, and it is advisable to avoid interference between the moving roller and the guide rail;
g. Loosen the electromagnetic relief valve handle to relieve the pressure of the system;
h. Adjust the directional valves to the right roller state;
i. Start the oil pump motor;
j. Same as b;
k. Observe whether the right roller advances flexibly. Similarly, the advance distance should not be too long;
l. Loosen the handle of the electromagnetic overflow valve to relieve the pressure of the system;
m. Adjust the directional valves to the left and right at the same time to enter the roller state;
n. Start the oil pump motor;
o. Same as d;
p. Observe whether the horizontal movement of the two rollers is flexible.
2. Debug the retreating oil circuit
a. Relieve pressure on the system;
b. Adjust the directional valves to the left retraction state;
c. Start the oil pump motor and adjust the loop relief valve to adjust the pressure to 4Mpa (read from the pump station pressure gauge);
d. Observe whether the roll back is flexible.
3. Use the roller inlet oil circuit to carry out the pressure holding test
a. Adjust the directional valves to the roll-in state;
b. The charging pressure of the accumulator is 8Mpa;
c. The upper and lower limits of the electric contact pressure gauge are set to PD upper=11Mpa, PD lower=9Mpa;
d. Adjust the overflow valve of the hydraulic pump station to make its pressure 10Mpa;
e. Adjust the solenoid valve pressure in the combined valve to make it slightly more than 10Mpa;
f. Under the above setting parameters, the system pressure is about 10Mpa. Keep the pressure at this pressure for 2 hours. Check the joints and flanges for obvious external leakage.
3. Lubrication system commissioning
Install the lubrication system, and pay attention to the temporary disconnection of the pipe joints of each lubrication point.
The lubrication system has a total of 14 lubrication points. The distribution of these 14 lubrication points is: four bearing seats, three lubrication points on each bearing seat, a total of twelve lubrication points, two lower guide rails, one on each guide. There are two lubrication points in total, and the amount of oil required for each lubrication point is based on the operating characteristics of the equipment, and the system will supply oil at points according to time and frequency.
The specific operations are as follows:
⑴ After installation, fill the lubrication pump with an appropriate amount of lubricating oil (about 30L);
⑵ Start the motor, pay attention to the positive and negative connection of the motor, and observe whether the pipe joints of each lubrication point are oily;
⑶ Since the length of each lubricating circuit is inconsistent, when the pipe joints of each lubricating point are out of oil, the oil supply switch of this oil circuit should be turned off immediately and connected to each lubricating point in order to avoid wasting lubricating oil.
⑷ On the premise that the lubricating motor does not generate heat, fill the guide rail and end cover with grease until you see the lubricating oil overflow.
⑸ Then according to the usage of each lubrication point of the equipment, in the control cabinet of the lubrication system, set the refueling times and refueling time of each lubrication point in sequence.
4. Testing system commissioning
1. Roll gap inspection and debugging
⑴Check whether the wiring of the primary instrument and the secondary instrument of the inductive displacement sensor is correct;
⑵Push the moving roller to the end, detect the original roller gap and make a record;
⑶ The movable rod of the twitch displacement sensor detects the linearity displayed by the secondary meter when the displacement is different;
⑷ Find out the linear working section of the inductive displacement sensor, and install the housing of the sensor in a suitable position;
⑸ Fix the movable rod of the displacement sensor on the bearing seat of the movable roller with the detected original roller gap as the initial quantity. And pay attention to whether its installation is firm.
2. Bearing temperature detection
⑴Check whether the wiring of the end surface thermal resistance and the secondary instrument wiring are correct;
⑵Use the standard thermometer to check whether the temperature error value of the end face thermal resistance within 0℃～80℃ is within the specified range of the product;
(3) Install the calibrated thermal resistance on the outer end cover of the main bearing. Note that the end face of the thermal resistance element should keep good contact with the outer ring of the main bearing. The spring on the thermal resistance should not be too tight to prevent damage to the components.
3. Hydraulic system pressure detection
⑴Check whether the wiring of the pressure sensor and display instrument is correct;
⑵Adjust the hydraulic system to different pressures. Adjust the indicated value on the display instrument. In the range of 2～12.0Mpa, the pressure display error is not more than ±0.3Mpa, and the error in the range of 7～11Mpa is not more than ±0.1Mpa.
4. Detection of normal operation of lubrication system
⑴Check whether the wiring of proximity switch and indicator light is correct;
(2) Install the proximity switch on the proximity switch mounting seat of the progressive distributor. Adjust the distance between the head of the proximity switch and the sliding rod of the oil separator to make it within the specified range;
(3) Start the oil pump motor and observe whether the indicator light of the proximity switch flashes regularly when the oil separator slide rod moves.