Experiment Study On Mechanical Properties Of Pellect Feed And Design Of Automatic Measurement Apparatus For Powder Content

With the vigorous development of China's aquaculture industry,the demand for feed products is increasing,at the same time,higher requirements are placed on feed quality.Pellet feed as the main feed product,and the powder content is one of the important processing quality indicators.Due to the change of processing conditions,and the storage,transportation and external friction,collision,and friction between particles,the pellet feed causes the pellet feed to be broken to increase its powder content.At present,feed processing plants still adopt the manual weighing?screening and weighing methods to calculate the powder content.In order to investigate the fragmentation characteristics of pellet feed,this paper collects 15 kinds of feed pellets,poultry,and aquatic products of 15 different specifications commonly used in the market,and adopts a texture analyzer(TMS-Pro)to axially compress and feed individual pellets.Compression and shear tests were performed on the particles using a universal universal material testing machine(RGN-6010).And this paper has designed and processed an automatic measuring device for powder content of pelleted feeds,which can detect the powder content of pelleted feed samples automatically and quickly.The main research contents and results are as follows:(1)The influence of the moisture content and aspect ratio of pellet feed on the ultimate strength of pelleted feed under axial compression?radial compression and shear test were investigated.In the three test modes,the axial compression ultimate strength was the largest,and the radial compression and the shear ultimate strength were equivalent.Among them,the ultimate compressive strength of pig pellet feed is between 0.56 ~ 4.34 Mpa,the ultimate tensile strength is between 0.25 ~ 1.40 Mpa,and the ultimate shear strength is between 0.25 ~1.44 Mpa;The ultimate compressive strength of poultry pellets is between 0.70 ~ 6.24 MPa,the ultimate tensile strength is between 0.37 ~ 1.99 MPa,and the ultimate shear strength is between 0.18 ~ 2.43 MPa;The ultimate compressive strength of fisheries pellet feed is between 1.66 ~ 7.68 MPa,the ultimate tensile strength is between 0.64 ~ 1.99 MPa,and the ultimate shear strength is between 0.45 ~ 3.11 MPa.According to data analysis,the aspect ratio has no significant effect on the strength,The moisture content has a significant influence on the strength and there is a critical humidity range that can satisfy the strength requirements and has a good molding effect.In addition,the analysis of the ultimate strength distribution of the three pellet feeds found that the ultimate strength of the three pellet feeds under the three test methods obeyed the normal distribution.Among them,the position parameters of the normal distribution of the ultimate compressive strength of pig pellet feeds are ?=1.69,the shape parameter is ?=0.93,the position parameter of the normal distribution of ultimate tensile strength is ?=0.54,the shape parameter is ?=0.18,and the ultimate shear strength is positive.The positional parameter of the state distribution ?=0.69,the shape parameter ?=0.28;the position parameter of the normal distribution of the ultimate compressive strength of the poultry pellet feed ?=2.58,the shape parameter ?=1.13,the position parameter of the normal distribution of ultimate tensile strength ?= 0.89,shape parameter ?=0.33,position parameter of normal distribution of ultimate shear strength ?=0.91,shape parameter ?=0.44;position parameter of normal distribution of ultimate compressive strength of aquatic product pellets ?=3.36,shape parameter ?=0.98 The positional parameter ? = 1.04 for the normal distribution of ultimate tensile strength,the shape parameter ? = 0.28,the position parameter ? = 1.06 for the normal distribution of ultimate shear strength,and the shape parameter ? = 0.40,indicating that the pig feed consistency is better.(2)The mechanical properties of the particle group,to explore the effect of the payload and dwell time on the feed content of the pelleted feed under axial compression conditions.Through CCD(Central Composite Design)response surface analysis,the payload and dwell time have an impact on the powder content and the load has a greater impact.When the payload increases by 400 N,the powder content increased by more than 90%,when the target load reached at 2000 N,the flour powder content has exceeded 4%.(3)An automatic measurement device with powder content was designed and processed.The device mainly consists of a drive system?screening device?weighing device and detection system.The working principle of the device was expounded.The overall structure design and the design of key components were carried out.A detection system based on the PLC read the serial data of the load cell,the display of the powder content display,and the data storage was developed.The test accuracy of the device was tested.The relative error of the weighing sensor weighing accuracy is within ±4.0%,and the average relative error of the detection accuracy of the powder containing rate is less than 10%.Under the existing conditions,through the mechanical properties test of the pellet feed,the key factors affecting the grain feed strength and the increase of the powder content were qualitatively analyzed to provide reference for the production process,production equipment,storage and transportation of the pellet feed.A device for automatic determination of the powder content of the pelleted feed was designed.The device can detect the powder content quickly and accurately and meet the needs of modern feed enterprises for the development of automation and intelligence.