The methods of the diagnostics and oil-and-gas installations state analysis reliability increasing based on usage of the parametric methods of statistics are discussed in this paper. The variance analysis of the mechanical properties of the pump rods made of normalized steel is given in this paper (according to the data of the manufacturing plant for the period of 10 years). It is found that breaking point and yield stress are distributed with the truncated normal laws in the region of minimum values. The obtained average values and variation coefficients of the mechanical properties within the steel grade permit to calculate the statistically significant changes of the mechanical characteristics. The correlations between Vickers hardness and breaking point (Vickers hardness and yield stress) in the case of steels produced in the Russian Federation for the pressure-operated vessels are also presented in this paper. These correlations permit to determine the strength characteristics with the relative error of 12% according to the hardness value. In the case of transferring the obtained correlations on the steels produced in Japan the systematic underestimation of the yield stress is 0,85 fold with respect to the value given in the certificate. The factors that influence on the microanalysis sensitivity and accuracy are revealed, the optimal scanning electron microscope mode and research conditions for the chosen patterns are also determined. Evaluation of the systematic inaccuracy of determining the carbon content in the steel is obtained in this paper. It is found that the measurement error for the scan area from 3 x 3 to 20 x 20 mm and accelerating voltage from 10 to 15 kv is minimal. The usage of the obtained results permits to increase the validity of the findings in the diagnosed installations condition evaluation and determining the conditions of their further exploitation.

Keywords: diagnostics, oil field equipment, parametric statistics, variance analysis, precision of measurements, mechanical properties, microanalysis

for snow removal from roads used by different snow-clearing equipment. The efficiency of its use is determined by the road conditions. This is especially true for snow plows in settlements with elements of arrangement of road (curbs, sidewalks, road barriers, stopping points). In these circumstances widespread machine dumps. The ability to develop, manufacture and operation of dumps of snow plows on small and medium-sized enterprises defines their widespread use and a variety of designs. Promising to modernize the necessary conditions under heaps of snow removal from roads and sidewalks. The decision in this case take into account the comprehensive approach, comprising as an account of the influence of external factors - the operating conditions of the machine, and internal changes in the parameters of the machine. Analysis of the problem has allowed to hypothesize on the design of blade snow removal machines. In order to develop a scheme blade methodology for the study and design of experiments, the basic factors of influence on the resistance. The design blade for snowplows and virtual model to assess performance.

Keywords: Blade, modernization blade, snowblower, snow removal from roads, research blade