Key Technologies For Secondary Stream Inoculation Process In Quantity Production Of Diesel Enginecylinder Block

As the main components of the engine,the cylinder block has been increasingly high demand in material and performance with increasingly fierce competition in the diesel engine industry.Secondary stream inoculation is an approach for inoculation,which is simple,less difficult or uncontrollable factors,suitable for high-volume production lines and considerable inoculation results,it is very conducive to enhancing and stabilizing casting performance to ensure and improve the quality of castings.According to company’s demands for diesel product development,this article show the key technology of secondary stream inoculation process in diesel engine cylinder block production with the study on secondary stream inoculation device development and application,inoculant quality control tests,inoculant granular control tests,inoculant volume and temperature tests and tests on avoiding casting defects spots.Followings are the main research results:1.Combined with the company’s actual production,we developed a frequency spiral auger motor secondary stream inoculation device,the imported secondary stream inoculation devices have also been digested,absorbed,and successfully applied to actual production.2.Anyang Jinzhao high quality inoculant(Si:70~75%,Ca:≤ 1.5%,Al:≤1.5%.)is suitable for our diesel engine cylinder block production with secondary stream inoculation process.Particle size of 0.2～0.8mm is the best with the flow of the secondary particle size inoculant.When the inoculant is less than 0.08%,the casting is in poor performance.Inoculant suitable dosage is 0.08 to 0.15%for Secondary stream inoculation treatment3.Type of secondary inoculant is closely related to the spots defects of cast.The alloy elements contained in the inoculant is the main factor,the more variety of alloy elements contained,the more spot defects.Secondly,the amount of alloying elements also has a certain impact on spot defects,higher content of alloying elements,more easily spotted,and vice versa.4.Core types are closely related to the generation of spots defects,castings with cold-box sand core(triethylamine France)is easy spotted,when using the hot-box sand core,spots defects are difficultly disappeared.5.Spots are caused as inoculant with alloy completely melted to liquid irondifficultly,and in the position of the cylinder block body bottom tank alloying elements such as the formation of uneven Ba enrichment,together with other factors,the formation of regional depolarization role in promoting the electrochemical corrosion,resulting in a short time to the casting surface alloying elements such as Ba-rich region as the center formation of abnormal rust.