Impact Damage Testing Study of Shanxi-Beijing Natural Gas Pipeline Based on Decision Tree Rotary Tiller Operation

The North China Plain and the agricultural region are crossed by the Shanxi-Beijing natural gas pipeline.Resi-dents in the area use rototillers for planting and harvesting;however,the depth of the rototillers into the ground is greater than the depth of the pipeline,posing a significant threat to the safe operation of the pipeline.Therefore,it is of great significance to study the dynamic response of rotary tillers impacting pipelines to ensure the safe opera-tion of pipelines.This article focuses on the Shanxi-Beijing natural gas pipeline,utilizingfinite element simulation software to establish afinite element model for the interaction among the machinery,pipeline,and soil,and ana-lyzing the dynamic response of the pipeline.At the same time,a decision tree model is introduced to classify the damage of pipelines under different working conditions,and the boundary value and importance of each influen-cing factor on pipeline damage are derived.Considering the actual conditions in the hemp yam planting area,targeted management measures have been proposed to ensure the operational safety of the Shanxi-Beijing natural gas pipeline in this region.

Development of Multi-purpose Small-sized Rotary Tiller for Greenhouses

IGLP-62 multi-purpose small-sized rotary tiller is a tool of production urgently needed for “Vegetable Supplying System”in China. It is mainly used for rotary cultivation as well as for fertilizer mixing and stubble mulching in greenhouses. And it can be used for open vegetable plots and orchards as well. The machine is characterized by the integration of rotary tilling with driving. It has a good performance of clod crushing and high capacity. It is equipped with a power-take-off shaft to drive a water pump, thresher or rice mill. Thus the machine solved the long-standing problem of heavy manual labour in greenhouses. So it is a kind of ideal hand cultivation machinery of horticultural type.

Design and experiment of anti-vibrating and anti-wrapping rotary components for subsoiler cum rotary tiller

The commonly used subsoiling cum rotary tiller machine(SRT)in Northern China is a combination of subsoiler and horizontal rotary tiller,however backfilling of the subsoiling slot,excessive vibration and plant residue wrapping on rotary components has been rarely considered.Therefore,the rotary components and assembly were redesigned to address these issues and to an SRT fitted with IT225 short curve rotary blades behind the V-shape subsoiling slots and IIT245 long curve rotary blades between the tines.Long and short blades were fitted on a rotor in a double helix,with optimal spiral angles of 65° and 90°,and phase angle of 147°and 180°,respectively.Compared with the commonly used SRT(CSRT),the additional anti-wrapping cutting blades in the circumferential and axial direction of ASRT could remove hanging residue on the blade holders,wrapping on the rotor and formation of an isolation layer.Moreover,the cutting edge curve of anti-wrapping cutting blades was an exponential curve.Field tests demonstrated that the redesigned SRT with anti-vibrating and anti-wrapping rotary components(ASRT)had was a significant advancement over the CSRT.Moreover,the working depth of rotary tillage was more stable,while other observations confirmed that backfilling of the subsoiling slot was also improved.

Optimal design of rotary tiller’s rotor and width proportionate to tractor power using energy method

The goal of the modern farming systems is to economize energy consumption and to reduce farming costs.Proper selection and use of agricultural machines are important factors to achieve this end.Rotary tillers are tillage tools that are used for accomplishment of both the primary and secondary tillage practices.Considering the widespread application of rotary tillers and wide use of modern tractors in Iran,optimal design of these machines is mandatory.Therefore in this study,the optimal working width and optimal diameter of the rotary tiller's rotor proportionate with the power of the MF 399 tractor was delineated based on the energy method.This theoretical method is based on the specific works of tractor and rotary tiller.Results showed that the optimal working width and optimal diameter of the rotary tiller’s rotor with maximum of forward speed 1 m/s for tractor was 240 cm and 6.27 cm,respectively.