Brief introduction to the method of effectively reducing the cavitation damage of the pump in operation (3)
6, using anti-cavitation material
Different materials have a very significant difference in cavitation resistance. There are many factors that affect the anti-erosion ability of materials. Generally, materials with high hardness and high elasticity are more resistant to erosion. Foreign recommended low-carbon chromium-nickel alloy steel, such as 13Cr4N as cavitation in the work of hydraulic machinery, has good resistance to erosion.
Zhengzhou Institute of Machinery Chen Yan conducted a comparison of the anti-cavitation properties of different materials ("Hot Processing Technology" 2000), the results are as follows
Material HT200 QT400-15 QT600-3 ZG230-450 ZG310-570
Weight loss mg 961.4 737.1 481.1 241 155
Test time h 15
Material ZG40Cr ZG20SiMn ZG1Cr18Ni9Ti ZG0Cr13Ni4Mo ZG0Cr13Ni6Mo
Weight Loss mg 139.9 122.2 71.5 40.2 25.2
Test time h 15 30
Zhu Xu Ren Changsha Pump Works provided information on the material and cavitation weight loss in the table below
Material HT200 QT600-3 ZG310-570 18-8
Weight loss 148.3 76.5 33 16.3
It is effective to use cavitation-resistant materials when cavitation can not be avoided. Such as: Lingcheng pumping station on the 7 # and 10 # units, the impeller room will be replaced by the original cast steel stainless steel, running a few years did not actually find the damage marks. Wuding gate station will be cast iron QT42-10, increased service life of more than 2 times. Jietai pumping station with cast iron and copper contrast, copper impeller anti-cavitation effect is obvious.
7, impeller protective layer
The method of coating the impeller is more commonly used, non-metallic coating epoxy resin, nylon powder, polyurethane and so on. The method of surfacing the alloy or sprayed alloy on the surface of the flow channel has also obtained certain effect on the cavitation destruction, such as stainless steel electrode surfacing method, stainless steel inlaid repairing method and alloy powder spray welding.
Compare several methods for non-metals and alloys, including stainless steel. Non-metallic coating economy, but should be strictly controlled the operation of its process to prevent the coating off the phenomenon. The use of alloy powder spray good but costly, and some places may not be able to proceed.
Such as: a pump station using metal alloy powder spray welding blade, and achieved good anti-cavitation effect, the service life can be extended. China Great Wall Aluminum Company Hao Baishun Hl pump impeller cavitation erosion coating applied research. Dazhuang Zhuang Duanzhuang pumping station pumping station serious cavitation, the use of soft ceramic composite repair 4 years 4000h water inspection found no cavitation damage. Wang Songchen, Songliao Committee of the Ministry of Water Resources, Metallurgical Reservoir Administration, introduced the application of TS216 wear-resisting agent in the anti-cavitation of turbine runner.
Lianyungang Water Supply Company MA Yu-East laser cladding method of cast iron and cast steel, the anti-cavitation performance were spray process 1.3 and 1.5 times.
8, trim the blade head
Trimming the impeller head to reduce the import of water flow rate of leaves to reduce impeller import crowding, improve the anti-cavitation pump capacity is effective. Practice has proved that despite the thinning of imported leaves, impeller life is often longer in the cavitation environment. General trim the impeller head is thinning the back of the blade head, near the impeller repair some more front cover.
2001 Changsha Pump Plant on the flow rate of 5040m3 / h, lift 17.5m pump dressing (while laryngeal dressing), the test found that the NPS decreased by about 0.5.
Different materials have a very significant difference in cavitation resistance. There are many factors that affect the anti-erosion ability of materials. Generally, materials with high hardness and high elasticity are more resistant to erosion. Foreign recommended low-carbon chromium-nickel alloy steel, such as 13Cr4N as cavitation in the work of hydraulic machinery, has good resistance to erosion.
Zhengzhou Institute of Machinery Chen Yan conducted a comparison of the anti-cavitation properties of different materials ("Hot Processing Technology" 2000), the results are as follows
Material HT200 QT400-15 QT600-3 ZG230-450 ZG310-570
Weight loss mg 961.4 737.1 481.1 241 155
Test time h 15
Material ZG40Cr ZG20SiMn ZG1Cr18Ni9Ti ZG0Cr13Ni4Mo ZG0Cr13Ni6Mo
Weight Loss mg 139.9 122.2 71.5 40.2 25.2
Test time h 15 30
Zhu Xu Ren Changsha Pump Works provided information on the material and cavitation weight loss in the table below
Material HT200 QT600-3 ZG310-570 18-8
Weight loss 148.3 76.5 33 16.3
It is effective to use cavitation-resistant materials when cavitation can not be avoided. Such as: Lingcheng pumping station on the 7 # and 10 # units, the impeller room will be replaced by the original cast steel stainless steel, running a few years did not actually find the damage marks. Wuding gate station will be cast iron QT42-10, increased service life of more than 2 times. Jietai pumping station with cast iron and copper contrast, copper impeller anti-cavitation effect is obvious.
7, impeller protective layer
The method of coating the impeller is more commonly used, non-metallic coating epoxy resin, nylon powder, polyurethane and so on. The method of surfacing the alloy or sprayed alloy on the surface of the flow channel has also obtained certain effect on the cavitation destruction, such as stainless steel electrode surfacing method, stainless steel inlaid repairing method and alloy powder spray welding.
Compare several methods for non-metals and alloys, including stainless steel. Non-metallic coating economy, but should be strictly controlled the operation of its process to prevent the coating off the phenomenon. The use of alloy powder spray good but costly, and some places may not be able to proceed.
Such as: a pump station using metal alloy powder spray welding blade, and achieved good anti-cavitation effect, the service life can be extended. China Great Wall Aluminum Company Hao Baishun Hl pump impeller cavitation erosion coating applied research. Dazhuang Zhuang Duanzhuang pumping station pumping station serious cavitation, the use of soft ceramic composite repair 4 years 4000h water inspection found no cavitation damage. Wang Songchen, Songliao Committee of the Ministry of Water Resources, Metallurgical Reservoir Administration, introduced the application of TS216 wear-resisting agent in the anti-cavitation of turbine runner.
Lianyungang Water Supply Company MA Yu-East laser cladding method of cast iron and cast steel, the anti-cavitation performance were spray process 1.3 and 1.5 times.
8, trim the blade head
Trimming the impeller head to reduce the import of water flow rate of leaves to reduce impeller import crowding, improve the anti-cavitation pump capacity is effective. Practice has proved that despite the thinning of imported leaves, impeller life is often longer in the cavitation environment. General trim the impeller head is thinning the back of the blade head, near the impeller repair some more front cover.
2001 Changsha Pump Plant on the flow rate of 5040m3 / h, lift 17.5m pump dressing (while laryngeal dressing), the test found that the NPS decreased by about 0.5.
The Hydraulic Filter Element is used in the hydraulic system to filter out particulate debris and rubber impurities to ensure the cleanliness of the hydraulic system.
The Filter Element is for high pressure section, medium pressure section, oil return section and oil suction section.
In order to reduce the dimensions of the filter element and increase the filtration area, the filter layer is generally folded into a corrugated shape, and the layer is generally pleated below 20 mm.
Test standard
ISO2942-ISO16889-ISO3968-ISO3724-ISO3723-ISO2943-ISO2941
Filter Element
Filter Element,Hydraulic Filter Element,Hydraulic Oil Filter Element,Oil Separator Filter Element
Xinxiang Shengda Filtration Technique Co., Ltd. , https://www.filtrations.nl