Oil vacuum pump maintenance

Oil-type vacuum pump is referred to as oil-type pump, oil-type vacuum pump is also known as oil-sealed rotary vane vacuum pump or oil-sealed mechanical pump. Therefore, the oil vacuum pump is the vacuum equipment product that uses the vacuum pump oil as the medium to seal the pump, so the maintenance of the oil pump should consider the replacement of the medium oil and the use of precautions.

Oil seal rotary vane vacuum pump is the most widely used oil seal single stage rotary vane vacuum pump, followed by water ring vacuum pump -2X double stage vacuum pump, this paper mainly introduces the maintenance of oil pump and vacuum pump oil replacement and use of several points for attention.

(A) The use of oil-sealed rotary vane vacuum pump need to pay attention to the following issues:

1. Mechanical vacuum pumps such as rotary vane vacuum pumps should be installed in a clean and clean environment, and the temperature should be within the range of 15 to 40 degrees.

2 When the rotary vane vacuum pump is connected to the power supply for the first time, check the steering of the motor. It is consistent with the steering of the rotor in the pump. Otherwise, the power supply should be stopped immediately to change the connection position of the two phases.

3. Before starting the vacuum pump each time, apply hand rotation or intermittent start several times to remove the oil in the rotary vane vacuum pump from the vacuum pump to reduce the resistance during starting.

4. When the vacuum pump needs to be stopped after use, the vacuum pump should be discharged into the atmosphere. Avoid pumping oil back into the system; For large mechanical vacuum pump, first put the atmosphere and then stop the pump. The use of electromagnetic reading with gas discharge is a better measure to ensure that the vacuum pump is deflated when the pump is stopped.

5. The oil temperature shall not exceed 75 degrees when the vacuum pump is running, and some real pumps should be cooled by water cooling to ensure that they have better parts.

6. It should be best to install a precision filter at the inlet of the real pump to eliminate oil vapor and not make it pollute the entire system. Precision filter for removing condensable steam. When removing corrosive gases, a corrosion-resistant mechanical vacuum pump should be used and equipped with a trap to eliminate the corrosion of corrosive gases on the vacuum pump and extend the service life of the vacuum pump.

In order to ensure that the rotary vane vacuum pump has better working performance and longer life, the maintenance and maintenance matters should be paid attention to during the use of the mechanical pump:

In the process of operation, the oil in the pump should be kept not lower than the standard line on the vacuum pump oil label. When refueling, do not mix different grades and types of vacuum pump oil.

Replace the vacuum pump oil regularly, generally 3 to 6 months to replace once, so as not to increase the difficulty of vacuum pump maintenance.

The reason of vacuum pump failure and the method of elimination

1. The vacuum is not high

[1] The temperature of the vacuum pump is too high, 1. The temperature of the pumped gas is too high. The gas should be cooled and then enter the vacuum pump, 2. The suction of hard objects will make the vacuum pump body wear. The vacuum pump should be disassembled to remove the hard objects and repair or replace the scratched parts. 3. The vacuum pump is not enough water flow. 4. Improper assembly will make the rotor axis displace, resulting in one-sided wear. Should be disassembled, inspected and reassembled.

(2) The vacuum pump oil has a problem, 1. The oil level is too low. Should add enough oil to show the center line of the oil label, 2. The oil is stained and the oil quality deteriorates. Should be replaced with new oil, 3. The brand of oil does not match. The specified brand of vacuum pump oil should be changed, 4. The oil circuit is blocked, and the appropriate amount of oil is not maintained in the vacuum pump chamber. Check the oil inlet of the oil circuit and the oil valve to keep the oil circuit unblocked.

(3) Vacuum pump itself leakage: 1. Seal leakage. Check the sealing conditions of all sealing parts and replace the damaged sealing ring. 2. The gasket of the gas ballast valve is damaged or not tightened. Replace the gasket and tighten the gas ballast valve; 3. The exhaust valve plate is damaged and the seal is not good. The air valve disc should be replaced; 4. When the diaphragm is pressed into the vacuum pump, the interference is too large, resulting in the deformation of the vacuum pump cavity and air leakage. The vacuum pump cavity should be trimmed or replaced. 5. Due to the poor oil seal of the end face of the vacuum pump, air leakage is caused. The end cover should be opened to check whether there is debris or irregularity, and cleaned or repaired.

(4) The rotor spring is deformed or broken and the spinning motion is not working. The spring deformation should be repaired or replaced to make the rotor product fit well.

(5) The air inlet filter is blocked. The filter should be removed, cleaned, and then installed,

(6) Excessive clearance caused by poor processing or wear. The matching gap between the vacuum pump chamber, rotor, rotary plate and end cover plate should be checked, and repaired or replaced according to the specified accuracy requirements.

(7) Friction heat during vacuum pump operation. The temperature rise is too high, so that the vacuum pump oil becomes thin, the sealing is poor. Cooling water or electric fan should be used to cool down, at the same time, check the clearance of relevant parts and repair or replace them according to the specified accuracy requirements.

Motor, vacuum pump abnormal operation, motor overload operation, vacuum pump in the operation of abnormal noise, noise, rotation difficulties or "stuck" phenomenon.

(1) Vacuum home temperature is too high, can refer to 1 paragraph (1) treatment,

(2) The spring is deformed or broken, so that the rotating plate is stressed unevenly and sends out an impact sound; The spring should be replaced.

(3) improper assembly, resulting in single-side wear, should be reassembled;

(4) The filter screen is damaged, metal chips, glass chips, etc., fall into the vacuum pump, making the operation of obstacles. The vacuum pump should be removed to check, remove debris, repair or replace worn parts, and install the filter.

(5) The vacuum pump cavity is seriously polluted, resulting in corrosion of parts. Should remove vacuum pump please wash, remove rust class, and change oil,

(6) The vacuum pump oil becomes milky. Viscosity increases. Should be replaced with a new vacuum pump oil,

(7) Vacuum pump chamber, shaft and shaft sleeve are too tight, tight into poor lubrication. The oil circuit should be reassembled and dredged and adjusted to strengthen lubrication

(8) The vacuum pump cavity is seriously polluted, resulting in corrosion of parts. Vacuum pump should be removed, please wash, remove rust spots, and change the oil,

(9) The motor is faulty and produces noise. The motor should be serviced or the bearing should be lubricated with butter.