Agricultural tractors performance levels. Comparison between hydraulic power test carried out according to OECD Code 1 and ISO 789-10

Agricultural and forestry tractors are equipped with quick-action hydraulic couplers designed to operate different implements used for agricultural and forestry works. Power supplied by the engine can be easily conveyed by high pressure fluid in pipes to the rotary tools or to cylinders drive apparatus with linear movements on agricultural machinery pulled, pushed or carried by tractors. Higher available oil flow and the rising number of connections for fluid power present on modern agricultural and forestry tractors increase interest in determination of the performance of their hydraulic system. Hydraulic power provided by agricultural and forestry tractors can be evaluated using the methodology included in a specific section of OECD Code 1 or following the procedure contained in ISO 789-10. As a result of the last review of ISO Standards some of the representatives of National Designated Authorities members of the OECD Standard Codes for the Official Testing of Agricultural and Forestry Tractors proposed to adopt ISO 789-10 test procedures in OECD Code 1, in order to improve harmonisation between Standards. Being involved in tractor testing according to OECD Codes, our Institute has been appointed to make comparative tests using both types of measurements to point out differences in results, costs and time required for execution. This paper presents the results of these trials.