vacuum equipment maintenance

What are the keys to maintaining vacuum equipment?
Answer: the key point of maintaining vacuum equipment is to judge the failure. Vacuum can not go up, there may be several reasons, we must make clear what is the reason, is the vacuum unit’s pumping capacity is not enough or the leakage rate is high; Or both. At this time, should be patient to observe and record, to find faults. For example, the pumping time is the same, and the vacuum degree is low, at this time, close the high-pressure valve, such as the vacuum gauge pointer quickly dropped, most of the cases are vacuum chamber leakage, at this time should first detect the leakage point. If the pointer of the vacuum gauge drops slowly, most of the cases are the vacuum unit pumping capacity is not enough, then you can focus on finding the vacuum pump and valve problems, see where there is a leak, or diffusion pump oil is contaminated, oxidation, etc.; Or the front pipeline seal is not good, insufficient pump oil; Or pump oil emulsion, shaft seal oil leakage, valve plate damage and other faults.

What are users most concerned about?
A: what users are most concerned about is the detection rate. Internal leakage and external leakage; Leakage is easier to detect, leakage is more difficult to do. Bigger leak point can use flame method, use the principle that airstream can make flame deviate, draw up vacuum first, with candle or lighter in can suspect the spot is searched in the vicinity step by step, can discover the flame moves toward leak point, can find leak point. We can detect the leakage in the working range of vane pump with the self-made leak detector, and now we have produced zhc.1 meter. The leak detector is detected with a zj.2 ionization gauge connected to the suction port of the vane pump. If the pump unit is diffused, the leakage rate of l0 Pa level can be detected.

How to check small leak and small leak?
Answer: small leakage and small leakage is more difficult to check, the common method is to use in a high vacuum ionization tube sensitive to some gases, such as acetone or ethanol, use a medical syringe to spray acetone or ethanol in suspicious places, spray to the leakage point, the ionization meter pointer will have a significant swing. Leak detection in this way must be patient, must wait until the ionization meter indication is stable, that is, the vacuum unit’s pumping capacity and leakage rate balance, before the injection. It is best to repeat several times to confirm the leak. The ZHC 1 meter can also be used to detect the leakage in the above method, the difference is that the ZHC. 1 meter can detect the leakage within the working range of the vane pump, and is not afraid of being exposed to the atmosphere.

In today’s power high-voltage equipment or instruments, with the quality and performance of the equipment or instruments to improve the requirements of the production of each link is also constantly improving, the production process is also changing and updating. Large main transformers and mutual inductors generally require vacuum oil injection to ensure that the internal water will not reduce the insulation performance of the equipment due to the moisture in the air, or even because the moisture content in the transformer oil exceeds the standard and the internal breakdown short circuit and other major accidents occur. In the field of medical equipment, X-ray machines and CT machines have been widely used in all kinds of clinical hospitals. A key component of X-ray machines and CT machines is the high-pressure generator or high-pressure ball tube, which also needs vacuum oil injection during production or maintenance.

In conventional die casting process, the use of vacuum assisted process to improve the mechanical properties of castings has always been an interesting topic for researchers and production departments. There have been many reports about this. The application of vacuum has been shown to reduce porosity in castings. The pore size in the casting is small and the distribution in the casting section is more uniform. Different from conventional die casting, semi-solid metal has high viscosity and different flow characteristics. Therefore, the research focuses on the influence of vacuum on the performance of die casting and the effect of casting system on vacuum during the die casting of semi-solid metal.