With the speedy development of economy and light industry heavy industry,the slurry pump is increasingly in demand. How to manufacture and process the good quality of slurry pump become the explore aim in academic circles.the paper narrates the application and materials of
slurry pump and the inserts are suitable for process the slurry pump component.
Firstly, the application and materials of slurry pump
The slurry pump also called centrifugal pump depend on the vortical impeller to make the increase mixed medium energy between solid state and liquid state.Meanwhile,the slurry pump can transform the electric power into dielectric kinetic energy and potential energy.
The slurry pump’s life is short, because the environment is bad with strong acid and strong base. To lengthen its life, our company adopt the high chromium white cast iron with high strength and hardness,corrosion resistance as mainly materials of slurry pump,such as Cr15Mo3，Cr15Mo2Cu，KmTBCr12 ，Cr20 ，Cr26 and so on.
High chromium white cast iron’s high hardness can get about HRC60 after the smith which one of best wear-resisting materials. The application fields mainly about mine, electricity, coal and environment protection with the corrosive solid slurry. The slurry pump will change with the different work surroundings such as coal washing industry, choose sea sand and dredge the waterway and other filed. Meanwhile, it also called the slime pump and the dredge pump.
Secondly, the process technic of component of slurry pump
The slurry has many components and mainly components have impeller,pump spindle,sheath,front and back guard board and installations.the slurry directly transmits the mechanical energy to liquid state, in order to add the static bolt-pressing and kinetic energy. The seal installation’s works avoid the inner of pump case liquid leakage alongside spindle and the air entering into the pump case.
Now we introduction the process technic of impeller and pump spindle of slush pump.
Picture 1: impeller
picture 2：pump spindle
The process technic of impeller: tough turning inlet port ring and front--finish turning pre-oral ring --keyseat--impeller balance hole-test-packing and warehousing
The process technic of pump spindle: tough turning-heat treatment-semi-finish turning--finish turning-Milling slot-external grinding--packing and warehousing
Pump impeller is only one to process other components in the slurry pump. Its materials usually adopt Cr26. The impeller has 5-12 impeller pieces.It is difficult for process impeller,because its have tow reasons: firstly, Cr26 can get high hardness through the smith, meanwhile, the forging defects often occurs in large forging parts,such as white cast iron and hardness points. Secondly, the impeller belongs to intermittent cutting which adds the degree of difficulty for process.
Thirdly, how to select the inserts for slurry pump components
Now,the process component for slurry pump has three inserts in the market: hard alloy cutter, ceramic cutting tool and PCBN. In comparison, the PCBN is more suitable for process components of the slurry pump.Because the hardness is high through the smith and hot treatment in slurry pump.the machinist early adopted the hard alloy cutter to process the slurry components ,but the hard alloy cutting’s hardness is not enough to lead to the inserts abrasion fast. Finally, the result is affect the affection and add the insert cost。
Ceramic cutting tool isn’t suitable for process the components of slurry pump. I can choose this to process the finish turning and a little use when we not consider the whole benefits of company
Above all,the tow methods can’t solve the problems. Until the Halnn hardness super hardness studied the BN-K1 to come true the tough turning of slurry pump.
From the hardness, BN-K1=traditional cubic boron nitrite>ceramic cutting tool>hard alloy cutter.
From the toughness, BN-K1>traditional cubic boron nitrite>hard alloy cutter>ceramic cutting tool.
Halnn superhard as a pioneer first put forward the concept that uses the cubic boron nitrite monolithic polycrystalline blade in the process of tough turning. PCBN applied comprehensive in the high hardness materials, high hardness components through heat treatment and other hard cutting. The PCBN breaks the problems that hard work materials with high hardness which have a high fame in the academic world.
Halnn superhard non-metallic adhesive cubic boron nitrite inserts BN-K1 have some advantages: the hardness and wear-resisting of PCBN is better than high alloy cutter; the strong impact resistance is better than the ceramic cutting tool and traditional cubic boron nitrite inserts. Meanwhile, it can process the components of slurry pump impeller with intermittent.
Now, we simple introduce the example of process of slurry pump impeller with halnn superhard inserts.
Fourthly, the example of Halnn superhard non-metallic adhesive cubic boron nitrite inserts BN-K1 to process the impeller
Machining materials: high chromium white cast iron Cr26
Process order: turning cylindrical,end face
Number: BN-K1
Cutting parameter: Vc=75m/min，Ap=2.5-5mm，fr=0.1mm/r
Processing method: intermittent cutting ；dry cutting
Processing effect: In turning impeller, because the impeller has 5-12 blades, the tool of impeller should bear 5-12 shocks every turn. BN-K1 Cubic Boron Nitrite Cutting Tool does not break in intermittent cutting process, and the cutting speed of Halnn Super Hard Non-metallic Adhesive Cubic Boron Nitrite Cutting Tool BN-K1 is higher than that of Ceramic Cutting Tool, while the single-edge life is 7 times longer than that of Ceramic Cutting Tool, which fully demonstrates the impact resistance of Cubic Boron Nitrite Cutting Tool with Non-metallic Adhesive, and not only reduces the cost of cutting tool. Cutting efficiency has also been improved.
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Materials
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Cutting speed
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Life/p
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Friction
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Halnn BN-K1
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75m/min
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7p/blade
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Normal friction
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Ceramic tips (some brand)
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35m/min
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1p/blade
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damaged
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Conclusion
Fifth,with the development of science and technology,the machinist try to make the component has a better life such as the slurry pump industry adopted the corrosion resistance and wearing-resisting’s materials which is intangible stress for inserts industry.The inserts only research the high quality and effective materials which can follow the steep of era.