Improvement Of Feed System Of Extrusion Granulator

Recently,extrusion pelletizing unit,as the core technical equipment in chemical enterprises for producing various resins,synthetic fibers and other products,has received considerable attention.High yield and high melt index has become the development trend of large-scale refining enterprises.It has complex structure,high operation difficulty and high fault frequency.In order to meet the increasingly competitive domestic market demand,refining enterprises must have a lot of production experience to deal with various difficult problems.It also needs to improve and break through the existing problems,especially the matching problem between cutting tool and module.It has restricted the stable operation of units for a long time.This dissertation will improve the feeding shaft of the cutter in the underwater granulation unit and develop a solution.Through the force analysis of the running feed axis,the formula of each component force can be obtained,the specific force value is calculated according to the actual parameters of the unit,and then the control area of the feed hydraulic oil pressure is obtained.In order to solve the reverse force of molten resin material on feed shaft in extrusion section of unit,the viscosity coefficient of resin under certain temperature,melting index and production load is firstly determined,then the relevant formulas of fluid mechanics are derived,and the specific reverse force formulas are finally calculated.The calculation method of formwork opening rate is also introduced to calculate the reverse force.The balance force calculation is carried out and the retract balance system is designed to solve the problem that the one-way constant thrust of the feed axis is easy to retract,which makes the cutter always maintains a balanced force,reduces the wear of the cutter and the template,reduces the number of machine failures and stops,as well as improves product quality.Finally,the improved knife feed balance system is verified through the knife sharpening experiment.This paper has made a breakthrough in the calculation of the reaction force of the molten resin material on the cutter and the derivation process of the six components of the cutter.By comparing the effects before,the number of unit failures downtime is greatly reduced after the improvement,the service life of fragile parts is improved,the product quality is also improved,and the product quality rate reaches 99.7%.Through analysis and improvement of the cutter feed system of the underwater pelletizing unit of the extrusion pelletizing unit,it calculates the specific value of the hydraulic oil pressure in the feed and the hydraulic oil pressure in the balance system,and confirms the relationship between the two.It has significant theoretical guidance value towards the specific operation of units in production practice,and it has changed the way adjustment used to be done only by experience.