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A cabin on an agricultural tractor is meant to protect the operator from harsh environment, dust and provide an air conditioned space. As it is an enclosed space, cabin structure should be a crashworthiness structure and should not cause serious injury to operator in case of tractor roll over. There are International standard like OECD Code 4, SAE J2194 which regulates the crashworthiness of this protective structure. The roll-over protective structure (ROPS) is characterized by the provision of space for a clearance zone large enough to protect the operator in case of tractor overturn. None of the cabin parts should enter into the clearance zone for operator safety. In addition to meeting ROPS test criteria, the cabin structural strength should be optimized for the required tractor life. In this paper, simulation process has been established to design an agricultural tractor cabin structure and its mountings to meet the above requirements.

A hydraulic power train assembly of an agricultural tractor is meant to lift the heavy implements during field operations and transportation. As it is a crucial member of the tractor for its usage, so the power train assembly needs a properly designed lift arm, rocker arm assembly with better strength and stiffness. There are a standard like IS12224, IS4468 which regulates the test method for hydraulic power and lift capacity of tractor and the layout of hydraulic three point linkage. Computer aided engineering techniques followed by laboratory testing have been deployed in the earlier stages of the product design & development itself to deliver the first time right products to the customer. In this paper, a virtual simulation process has been established to design an agricultural tractor hydraulic lift arm to meet the above requirements. A Design Verification Plan (DVP) has been developed consisting of 3 load cases.

Roll-over protective structures (ROPS) are safety devices which provide a safe environment for the tractor operator during an accidental rollover. The ROPS must pass either a dynamic or static testing sequence or both in accordance with SAE J2194. These tests examine the performance of ROPS to withstand a sequence of loadings and to see if the clearance zone around the operator station remains intact in the event of an overturn. In order to shorten the time and reduce the cost of new product development, non-linear finite element (FE) analysis is practiced routinely in ROPS design and development. By correlating the simulation with the results obtained from testing a prototype validates the CAE model and its assumptions. The FE analysis follows SAE procedure J2194 for testing the performance of ROPS. The Abaqus version 6.12 finite element software is used in the analysis, which includes the geometric, contact and material nonlinear options.

A tractor is vehicle specifically designed to deliver a high tractive effort at slow speeds for carrying out various agriculture operations like ploughing, rotavation etc. using implement. Hydraulic system is a key feature which connects these implements with the tractor. It controls the position and draft of the implement depending upon the type of crop, farming stage, implement type and soil conditions. These variations induces extreme range of load on the hydraulic system, thus making it challenging to design these components. Bell crank assembly is one of the main components of hydraulic system which controls the draft (thus, the loads experienced by tractor) through load sensing mechanism. Often bell crank assembly failures are reported from field due to uneven soil hardness and presence of rocks. This paper studies one of such bell crank assembly failures in the field. The failure was reported after half life cycle of usage during agriculture Operation.

The tractor engine related mounting brackets are very critical due to different aspects of vehicle performance, durability and noise. These mounting bracket have been designed as a framework to support engine external parts like muffler, exhaust tail pipe, alternator etc. Vibration and fatigue has been continuously a concern which may lead to structural failure and performance issues. Various such failures are faced regularly by automotive industry and finite element based analysis are used to resolve them. The resolution is done by playing with the component thicknesses, material, by providing additional support etc. However, due to large degree of uncertainty associated with the loading, boundary conditions, manufacturing, environmental effects; still there is some probability of failure. This paper focuses on a field failure issue of an exhaust system of a tractor and subsequent concern resolution.