Vacuum pump impeller material choice
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I plant in 1998 on a pipeline pumping water to carry out the reform, new water pipes DN850 II 70m, and a suction tube and secondary rainbow siphon suction tube pumping Road series, a total length of 100 m. Design of vacuum pumps for water diversion.
     Shandong selection of a vacuum pump factory produced water ring vacuum pump-SZ-3, and then test the installation in November to meet the design requirements of the people to vote.
     First, the accident occurred
     SZ-3-type vacuum pump on a normal operation, start running, the body pumps have abnormal sound, immediately shutdown. , Inc., manufacturer, supplier of vacuum pumps for the dissolution of the three on-site inspection found that all the cast iron pieces of broken impeller, the pump can no longer use.
     In the first manufacturer to repair and replacement after the first run in both the leaves varying degrees of damage.
     Second, the failure analysis and processing
     SZ-3 in the use of vacuum-Secretary for 1 year and a half years, with a total running time for just over 800 h, appeared three times in a row impeller damaged, it is rare.
     Analysis of the causes of equipment failure, the following points.
     (1) quality of the equipment in question;
     (2) have a hard object into the vacuum pump in the body;
     (3) equipment in violation of rules;
     (4) conditions for the use of improper equipment.
     We have ruled out the above (1), (2), (3), an analysis of key pieces made of cast iron impeller, as the material itself, the existence of stress, long-term easily broken by external shocks. In addition, cement, sand content is too high, the pipeline is too long to start vacuum pumps, big impact Instant pressure. Under these conditions, the use of cast iron impeller, the impeller may be damaged a major factor. To this end, the purchase of the maker of ductile iron impeller to be replaced. Vacuum pump repair re-trial operation so far, more than four years ago, has been operating normally, good.
     Third, the experiences and lessons
     1. Equipment selection, should pay attention to "core" elements of performance. The use of vacuum pumps, impeller must pay attention to the material. According to the specific conditions of use materials scientifically.
     2, in the water supply and drainage design of water pumps, vacuum equipment, the same type of materials with different impeller, should be focusing on, easy-to-use unit selection.
     3. Vacuum pump manufacturers in product specification, the impeller should be to introduce a variety of materials, performance, terms and conditions applicable to guide users to choose the right.