Determination of gas concentration in the lubricant of transmissions of energy-saturated agricultural tractors
Ensuring the trouble-free operation of the transmission during the operation of energy-saturated tractors is an important task. The reliability of its operation largely depends on the presence of gas in the lubrication system. The aim of the study is to develop a methodology for determining the quantitative content of gas in a gas-oil mixture. In the tractor transmissions, the composition of the gas-oil mixture can have different values, which are determined mainly by the geometric dimensions of the elements of the assembly units, the speed mode of operation, the temperature and the grade of the lubricant. The influence of these parameters can be determined by recording the composition of the gas-oil mixture during tests, both assembly units and transmissions in general, when mounted on a test bench or on a tractor. The choice of the method for recording the composition of a gas-oil mixture was carried out on the basis of an analysis of a number of studies in which various techniques for analyzing the composition of two-phase mixtures are given. Demonstrating the requirement of universality of the method, consisting in a uniform method of its application, both in bench and in object conditions, the most interesting is the method associated with sample sludge. The most successful points of the transmission lubrication system are suggested, from which it is most convenient to take samples, as well as those characterized by the largest content of gas in the oil. Also the most simple and informative method for determining the volumetric gas content in the mixture is proposed. Calculated dependences are derived, allowing to take into account the change in the volumetric ratio of oil to gas during the sampling time. The developed method allows to make an assessment of the required capacity of bilge pumps of forced lubrication systems. The technique can be used both for bench and for road tests.