1. Macleod vacuum gauge, also known as MacLeod vacuum gauge (also known as rotary compression vacuum gauge), is designed according to Boyle mallott's law of ideal isothermal compression. Because it can directly calculate the pressure value through its own parameters, in addition to pressure measurement, it can also be used as an absolute vacuum gauge to verify some relative vacuum gauges (for example, seat compression vacuum gauge is one of them), so it is widely used in vacuum measurement in industry, national defense, scientific research, medicine, refrigeration and so on.

2. The PM-2 combined vacuum meter produced by our company includes the measurement range of PM-3 and pm-4, which is divided into two stages: 200Pa ~ 10000pa and 0.1pA ~ 350pa, which covers the original products of pm-4 and PM-3. At present, our company mainly produces PM-3, which has higher accuracy and smaller volume than the traditional pm-4.

1. Before use, lift up the vacuum exhaust pipe and put the vacuum gauge under it to prevent the mercury beads in the glass pipe from sliding into the exhaust pipe during transportation. Then pull up the rubber stopper, apply castor oil or vacuum grease on the inner wall of the exhaust pipe orifice, directly connect it to the interface of the measured vacuum system, turn on the mechanical vacuum pump for about 3-5 minutes, and then slowly open the vacuum valve outside the vacuum meter. At this time, the instrument enters the working state.

2. If the vacuum degree of the vacuum system is coarse vacuum, for the PM-2 type, the pressure of the U-shaped vacuum gauge on the right is right. Its reading value is the sum of the scale values indicated by the two mercury beads. When the true vacuum degree is lower than 0.2kpa (i.e. 200Pa), the end faces of the two mercury columns are basically parallel, it is necessary to look at the vacuum gauge on the left. Its operation method is the same as that of the original Michaelis vacuum gauge (as shown in the surface printing).

1. During transportation and use, it must be strictly prevented from lying upside down, so as to prevent the waterproof silver from falling back into the vacuum image tube or mercury beads from entering the middle closed tube capillary to block the capillary, which will affect the measurement accuracy. Therefore, the vacuum rubber tube must be vertical before each use, so that the mercury can flow back into the vacuum gauge glass tube.

2. When measuring, i.e. the vacuum gauge is in an upright state. It is strictly prohibited to strongly rush any gas into the vacuum system to avoid impacting the glass tube and breaking the glass tube.

3. The working mercury in the vacuum gauge has been treated by chemical and physical methods and has a certain cleanliness. Mercury oxidation pollution caused by long-term use and other reasons will directly affect the measurement accuracy. It should be sent to repair in time and can be used only after passing the inspection.

4. After the measurement of the vacuum gauge, clamp the vacuum rubber tube with a clamp and isolate it from the gas of the vacuum system. In this way, the mercury in the vacuum gauge can be kept clean, and when the vacuum gauge is removed and separated, the atmosphere will strongly impact the vacuum gauge to break it. If the vacuum gauge is not removed, after the mechanical vacuum pump stops, be sure to disconnect the gas circuit between the mechanical pump and the vacuum system, and put the mechanical pump into the atmosphere to prevent the mechanical pump oil from returning to the vacuum system and the vacuum gauge from being polluted by oil.

PM-2

10kPa-0.2kPa 350Pa-0.1Pa

The U-type meter is grade 2.5, and the Michaelis meter is ± 40% jjg540-88

Q/SSUPC01-2001

PM-3 650Pa-0.1Pa ±40% Q/SSUPC01-2001

PM-4 650Pa-0.1Pa -50%-80% Q/SSUPC01-2001